ArticlePDF Available

Revision of the extant Polypteridae (Actinopterygii: Cladistia)

July 2019
Ichthyological Exploration of Freshwaters

DOI:10.23788/IEF-1094

Authors:

Timo Moritz

Deutsches Meeresmuseum

Ralf Britz

Senckenberg Natural History Collections Dresden

The species-level taxonomy of all extant members of the family Polypteridae is revised. Two genera are recognised: Polypterus and the monotypic Erpetoichthys. Thirteen species of Polypterus are regarded as valid: P. bichir (type species), P. ansorgii, P. congicus, P. delhezi, P. endlicherii, P. mokelembembe, P. ornatipinnis, P. palmas, P. polli, P. retropinnis, P. senegalus, P. teugelsi and P. weeksii. Polypterus lapradei and P. bichir katangae are considered junior synonyms of P. bichir. Polypterus senegalus meridionalis is synonymized with P. senegalus, and P. buettikoferi and P. retropinnis lowei are regarded as junior synonyms of P. palmas. Lectotypes of P. ansorgii, P. congicus and P. delhezi are designated. Distribution maps for each species are compiled and a key for all species of Polypteridae is provided.

Overview of principal color patterns in Polypterus.

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Polypterus ansorgii, BMNH 1910.9.13.4, 169 mm SL, juvenile or female, lectotype (present designation); Guinea Bissau: Corobal River at Tchitoli; W. J. Ansorge; Jun 1909.

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Records of Polypterus ansorgii. , type locality; , verified records.

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Polypterus bichir, MNHN 0000-5761, 585 mm SL, male, lectotype; Egypt: Nile; E. Geoffroy Saint-Hilaire; 1799.

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+38

Polypterus bichir, NMW 63244, 464 mm SL, male, syntype of P. lapradei; Taoué close to Richar-Toll [= ToueyMarigot]; F. Steindachner; Nov 1868.

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Ichthyological Exploration of Freshwaters/IEF-1094/pp. 1-96 Published 23 July 2019

LSID: http://zoobank.org/urn:lsid:zoobank.org:pub:9FEAF636-6AA5-49B0-BEA4-2CCD75EBE13E

DOI: http://doi.org/10.23788/IEF-1094

Ichthyol. Explor. Freshwaters – ISSN 0936-9902 (print)

Revision of the extant Polypteridae

(Actinopterygii: Cladistia)

Timo Moritz* and Ralf Britz**

The species-level taxonomy of all extant members of the family Polypteridae is revised. Two genera are recog-

nised: Polypterus and the monotypic Erpetoichthys. Thirteen species of Polypterus are regarded as valid: P. bichir

(type species), P. ansorgii, P. congicus, P. delhezi, P. endlicherii, P. mokelembembe, P. ornatipinnis, P. palmas, P. polli,

P. retropinnis, P. senegalus, P. teugelsi and P. weeksii. Polypterus lapradei and P. bichir katangae are considered junior

synonyms of P. bichir. Polypterus senegalus meridionalis is synonymized with P. senegalus, and P. buettikoferi and P. re-

tropinnis lowei are regarded as junior synonyms of P. palmas. Lectotypes of P. ansorgii, P. congicus and P. delhezi are

designated. Distribution maps for each species are compiled and a key for all species of Polypteridae is provided.

* Deutsches Meeresmuseum, Katharinenberg 14-20, 18439 Stralsund, Germany; and Institute of Systematic

Zoology and Evolutionary Biology, Friedrich-Schiller-University Jena, Erbertstr. 1, 07743 Jena, Germany.

E-mail: timo.moritz@outlook.com (corresponding author)

** Department of Life Sciences, The Natural History Museum, Cromwell Road, London, SW7 5BD, United

Kingdom. E-mail: r.britz@nhm.ac.uk

Introduction

Since their discovery, polypterids continue to puz-

zle scientists. Due to their phylogenetic position as

the most basal extant actinopterygians (Patterson,

1982; Min & Schultze, 2001), polypterids have at-

tracted a lot of scientific attention (see Gosse, 1984

for literature until 1983). Polypterids show several

character states that are considered primitive for

actinopterygians or even bony fishes, e. g. a pair

of true lungs, a body armour of thick ganoid

scales (Sire, 1995), a holoblastic egg development,

(Kerr, 1907; Bartsch et al., 1997) and functional

spiracles (Magid, 1966). They also show many

autapomorphies most of them not known from

any other fish group, fossil or extant, like separate

dorsal finlets, cartilaginously preformed epicen-

tral intermusculars that articulate with the ganoid

scales distally (Britz & Bartsch, 2003), a highly-

specialized anatomy of the pectoral fin (Jessen,

1973), a reduced number of gill arches (Britz &

Johnson, 2003), convergent in some anguilliforms

(Nelson, 1966), and a unique sexually dimorphic

anal fin associated with a unique mating behavior

(Holden, 1971; Britz & Bartsch, 1998).

Despite the numerous papers that have fo-

cussed on bichirs in the past, the species-level

taxonomy of polypterids is still poorly studied.

The number of nominal valid species of poly-

pterids is inconsistently cited as 9 species and 5

sub-species (= 14 taxonomic units in Poll, 1941a),

9 species and 6 sub-species (= 15 taxonomic units

in Gosse, 1984), 18 species of which 5 supposedly

represent undescribed species (Schäfer, 2004), or

Moritz & Britz: Revision of Polypterus

10-15 species (Britz, 2004). The major reason for

the inconsistency in species numbers is the un-

resolved nomenclatural status of several species-

group names. The goal of the present study is a

species-level revision of the extant Polypteridae

in order to provide a comprehensive taxonomic

framework for future studies on extant members

of this family.

Material and methods

Studied specimens are listed under each species.

The material is divided into two categories: ‘Mate-

rial examined’ contains all specimens for which

meristic information and/or measurements were

incorporated into the study. ‘Additional mate-

rial’ contains lots, which have been verified for

their species identity and of which their locality

information has been used for the compilation of

distribution maps.

Measurements used are listed below and

illustrated in Figure 1. All measurements were

taken point to point with digital callipers (CD-

20DCX Absolute Digimatic, Mitutoyo) to the

nearest 0.1 mm for all distances up to 160 mm.

Any measurements above this value were taken

with rulers to the nearest mm. In the case of dis-

torted specimens we used a non-elastic cord to

record the distance between landmarks and then

measured this distance on a ruler.

The following abbreviations have been used

for morphometric and meristic data: AFB, length

of anal-fin base; AFL, length of longest ray in

anal fin; AR, number of anal-fin rays; BD, body

depth at tip of pectoral fin; BW, body width at

tip of pectoral fin; CPL, caudal-peduncle length:

distance between end of anal fin and ventral

origin of caudal fin; D1L, length of first dorsal-

fin spine; D1W, width of first dorsal-fin spine

at its base; D2L, length of second dorsal-fin

spine; DCR, number of soft rays in confluent

dorsal and caudal fin; DFL, length of spinous

part of dorsal fin: distance between base of first

dorsal-fin spine and base of first dorsal-fin soft

ray; DisPD, distance from distal tip of adducted

pectoral fin to first finlet (if first finlet is positioned

in front of tip of pectoral fin, measurement will

have negative value); DS, number of dorsal-fin

spines, including separate finlets and posterior-

most spine connected to soft-rayed portion of

dorsal fin; EyD, eye diameter; GuL, gular length:

distance between tip of lower jaw along mid-

ventral line and caudal most extension of both

gularia; HL, head length: distance between tip

of snout and posterior border of opercle (not in-

EyD

prePL

NOD

preVL

preAL

AFL

GuL

SnL PoL

SnPL

preDL

DFL

DistPD

AFB

BD CPL

IOW HW D1W IPW

PBW

D1L

D2L

AFB

BD CPL

IOW HW D1W IPW

PBW

D1L

D2L

EyD

prePL

NOD

preVL

preAL

AFL

GuL

SnL PoL

SnPL

preDL

DFL

DistPD

AFB

BD CPL

IOW HW D1W IPW

PBW

D1L

D2L

AFB

BD CPL

IOW HW D1W IPW

PBW

D1L

D2L

Fig. 1. Representation of measurements used in this study. For abbreviations see text. Based on the figure of

Polypterus senegalus from Boulenger (1907).

Ichthyol. Explor. Freshwaters, IEF-1094

cluding fleshy opercular membrane); HW, head

width at anterior border of opercle; IoW, inter-

orbital width: distance between upper margins

of orbitae; IPW, inter-pectoral width: distance

between ventral bases of left and right pectoral

fins measured in ventral view; NoD, nostril

distance at base of nasal tentacle; PBW, width of

pectoral-fin base directly at insertion; PoL, post-

orbital length: distance from posterior border of

orbit to posterior border of opercle; PR, number

of pectoral-fin rays; preAL, pre-anal length:

distance between tip of snout and origin of anal

fin; preDL, pre-dorsal length: distance between

tip of snout and first dorsal-fin spine; prePL,

pre-pectoral length: distance between tip of snout

and base of pectoral fin at insertion; preVL, pre-

pelvic length: distance between tip of snout and

base of pelvic fin at insertion; PvR, number of

pelvic-fin rays; ScB, scales around body at tip of

pectoral fin; ScpD, pre-dorsal scales; ScL, scales

in longitudinal series; ScpP, pre-pelvic scales

(including interpelvic scale); SL, standard length:

distance between tip of snout and posterior most

body scale; SnL, snout length: distance between

tip of snout and anterior margin of orbit; SnPL,

extension of pectoral fin: distance between tip of

snout and posterior end of adducted pectoral fin

placed flat on the body; TL, total length: from tip

of snout to tip of caudal fin; TVer, total number of

vertebrae, only vertebrae with an ossified centrum

are counted here, so that the actual first vertebra

which has no centrum (Britz & Johnson, 2010) is

not counted.

In addition to meristic and morphometric dif-

ferences species of the Polypteridae can also be

distinguished by their color pattern. The recurring

elements of the color pattern are (Fig. 2): pectoral-

fin base blotch: a well-defined dark brown to

black blotch laterally in the distal portion of the

pectoral-fin base; dorsal blotches: a series of black

markings, several scale rows in width, usually

reaching across dorsum to other side forming

saddle-like blotches; lateral blotches: a series

of midlateral dark markings extending several

scale rows in width; dorsolateral bars: formed

by confluence of dorsal and lateral blotches, ei-

ther directed obliquely anteriorly (when dorsal

blotch is confluent with preceding lateral blotch),

or directed obliquely posteriorly (when dorsal

blotch is confluent with succeeding lateral blotch);

sometimes expressed as x/y-shaped bars (when

dorsal blotches confluent with both preceding

and succeeding lateral blotches); ventrolateral

markings: dark brown to black markings along

the ventrolateral sides of the body, often expressed

as series of dark spots, one scale wide and form-

ing irregular interrupted lines (as in some color

morphs of P. bichir or in P. ansorgii) or irregular

speckling of ventrolateral body; sometimes also

forming larger blotches that may be confluent

with lateral blotches (as in P. endlicherii); subor-

bital stripe: an oblique dark brown to black stripe

below the eye extending from the posterior base

of the nasal tentacle to the margin of the jaw ar-

ticulation or sometimes expressed only in part of

this distance (as in the postorbital area in P. polli)

and/or expressed as a line of separate spots rather

than as a continuous stripe (as in P. retropinnis);

lip markings: brown to black markings of varying

shape and size, can be expressed as vermicula-

tions on both lips, as peppering with tiny spots,

as a series of bar-like markings or a combination

of all; dorsal and lateral head markings: brown

to black or light beige markings of varying shape

and size, can be expressed as vermiculations, spots

or blotches.

Distribution data of all checked museum

specimens were critically evaluated and, when

found to be lacking precision, were given ap-

proximated GPS coordinates. Locality information

that was considered too general, such as “River

Nile”, “Senegal” or “Congo” was not included.

dorsal head markings

lip markings

suborbital stripe

pectoral-fin base blotch lateral blotches ventrolateral markings

dorsal blotches

dorsolateral bars

lateral head markings

Fig. 2. Overview of principal color patterns in Polypterus.

The distribution data were complemented by

information obtained by TM during several field

trips. In addition, museum and internet databases,

i. e. Fishbase (Froese & Pauly, 2016) and fishnet2

(www.fishnet2.net), were checked for distribution

data, but this information was critically evaluated

and questionable records were not included. Last-

ly, numerous published sources of distributional

information were evaluated, [e. g. Pellegrin (1900),

Blanc & Daget (1957), Paugy & Bénech (1989), Ro-

man (1966), Moritz (2010), Neumann et al. (2016)].

Locality records are grouped into four categories

(1) type locality, (2) verified records, i. e. the spe-

cies identity of the respective specimens has been

checked and confirmed in this study, (3) other

records, i. e. records from literature and database,

for which specimens could not be checked, but

for which locality records are plausible, and (4)

questionable records; i. e. records that could not

be verified but that seem to be based on correct

identifications, but are considered questionable in

the context of the other records. Doubtful records,

i. e. records that are almost certainly based on

misidentifications have been excluded from the

maps, but discussed for each respective species, to

produce the most comprehensive, up to date dis-

tributional information for the different species.

Data were collected in tables from which maps

were created with the freeware QGIS 2.12.3 (www.

qgis.org) using freely available shape files from

FAO, as e. g. ‘Rivers of Africa’ and ‘Inland Water

Bodies of Africa’ (www.fao.org/geonetwork).

Simple diagrams and box-plots were created

directly in table calculation software EXCEL

(Microsoft Corp.) or CALC (OpenOffice 4.1.1,

www.openoffic.org); statistical calculations such

as Principal Components Analyses (PCAs) were

conducted in PAST 3.11 (Hammer et al., 2001).

Graphics including figures were either created

or at least finalized with the software GIMP 2.8

(www.gimp.org). For Polypterus palmas several

characters were analyzed and displayed accord-

ing to the river system where the specimens were

collected, following a North to South sequence of

the respective deltas of the basins.

The following institutional abbreviations have

been used: BMNH, The Natural History Muse-

um, London; DMM, Deutsches Meeresmuseum,

Stralsund; IRSNB, Institut Royal des Sciences Na-

turelles de Belgique; MNHN, Muséum national

d’Histoire naturelle, Paris; MRAC, Musée Royal

de l’Afrique Centrale, Tervuren; NMSZ, National

Museums Scotland, Edinburgh; NMW, Naturhis-

torisches Museum, Vienna; RMNH, Naturalis

Biodiversity Centre, Leiden; USNM, National

Museum of Natural History, Washington, D.C.;

ZSM, Bavarian State Collection of Zoology, Mu-

nich.

Family Polypteridae Bonaparte, 1835

Polypterini Bonaparte, 1835: 8.

Type genus. Polypterus Lacépède, 1803 (see re-

marks under Polypterus below).

Diagnosis. Polypterids are distinguished from

all other living actinopterygians by the presence

of complete ganoid scales covering the entire

body, a unique skeletal anatomy of the pectoral

fin, first part of dorsal fin separated into finlets,

i. e. sharp spines with secondary supporting rays

and attached membrane, as well as paired lungs

with ventral connection to oesophagus, a modi-

fied anal fin in males, adhesive eggs and larval

stages with external opercular gills.

Descriptive synopsis. Two types of body shapes

among polypterids: elongated, cylindrical in

Polypterus (body depth 7.0-16.5 % SL) and an-

guilliform in Erpetoichthys (body depth 2.9-5.2 %

SL); body in both types round in cross section at

anterior third and laterally flattened at posterior

third. Head in cross-section round or moder-

ately to strongly dorso-ventrally flattened. Body

completely covered with fully developed ganoid

scales consisting of three layers: bone, dentin and

ganoin (Goodrich, 1907; Sire, 1995). Anterior part

of dorsal fin separated into 5-18 finlets, i. e. single

spines with sharp bilaterally paired distal tips

with posterior fin membrane supported by soft

rays originating from posterior margin of spine

perpendicular to spine body. Posterior part of

dorsal fin confluent with caudal fin. Pectoral-fin

skeleton with unique pro-, meso- and meta-

pterygium between pectoral girdle and pectoral

radials. Sexually dimorphic anal fin: fin of males

greatly enlarged mainly as result of anteropos-

terior widening of anal-fin rays; number of

anal-fin rays on average only slightly higher in

males of Polypterus, but clearly higher in males

of Erpetoichthys.

Mouth large, with posterior angle situated

behind vertical through posterior margin of orbit;

lips thick, supported by labial cartilage. Anterior

Moritz & Britz: Revision of Polypterus

nostril extended as tube well beyond tip of snout.

Paired gular plates present. Interopercle absent.

Series of spiracular plates between lateral margin

of skull roof and opercular series, with some of

them covering the functional spiraculum (Bartsch,

1997; Claeson et al., 2007). Dermohyal present.

Maxilla immovably attached to skull (akinetic

upper jaw). Fifth gill arch absent and lower phar-

yngeal tooth plates associated with fourth cerato-

branchial (Britz & Johnson, 2003); pseudobranch

absent. Juveniles with well-developed external

opercular gills. Mesocoracoid absent; clavicles

well developed. Unique epicentral intermuscular

bones with cartilaginous tip articulating with

lateral line scales (Britz & Bartsch, 2003). Intestine

with spiral valve. Caudal fin rounded or pointed

(especially in juveniles) confluent with posterior

dorsal fin; posterior most vertebrae smaller than

preceding ones.

Biology. For most species information on ecology

and life history is scarce. From the available and

published information it seems that species are

quite similar to each other in various aspects. All

are predominantly nocturnal and strictly fresh-

water species. They are predators, apparently

mostly guided by their sense of smell (Pfeiffer,

1968, 1969), feeding on aquatic and terrestrial

invertebrates and fish, sometimes amphibians,

with prey size mainly depending on the size of

the mouth cleft of the respective specimen. Some

plant material has occasionally been reported

from stomach contents (e. g. Daget, 1948), but was

likely ingested accidentally. Polypterus species

are able to prey on fishes of more than half their

size (pers. obs. TM). Prey can be sucked in with

force and speed by enlarging the mouth cavity

and projecting the cartilage-supported labial folds

to form a funnel (Bartsch, 1997). All polypterids

show sexual dimorphism in their anal fin, which

is important for courtship: during spawning, the

male forms a ‘cup’ with its anal fin into which

the female releases her eggs. Eggs are then ferti-

lized in this ‘cup’ before being scattered by rapid

lateral movements of the caudal and anal fins of

the male (Bartsch & Britz, 1996; Britz & Bartsch,

1998). The anal fin of males does not function

as a copulatory organ as initially hypothesized

by Harrington (1899). In nature, spawning takes

place in (densely) vegetated areas, usually flood

plains (Budgett, 1900; Daget, 1948). The eggs are

relatively large and adhesive (Arnoult, 1961, 1964;

Bartsch & Britz, 1996) with a single micropyle

(Britz & Bartsch, 1998). The larval development

was described in detail for P. senegalus (Kerr, 1907;

Bartsch et al., 1997; Schugardt & Kirschbaum,

2006), and for P. ornatipinnis and E. calabaricus

(Britz & Bartsch, 1998). When larvae start to

feed in captivity, they wait for prey rather than

actively search for it (Bartsch, 1997). Juveniles

have external gills (Boulenger, 1902b), which may

persist for a long time up to even larger sizes in

some species (e. g. large external gills were still

present in a 335 mm SL specimen of P. weeksii

[MRAC A7-033-P-0028], a 334 mm SL specimen

of P. bichir [BMNH 1900.6.28.9], a 315 mm SL

specimen of P. congicus [IRSNB 9960], and in

a 279 mm SL specimen of P. endlicherii [NMW

63218]). In captivity larvae and juveniles initially

show fast growth up to a certain, species-specific,

size but subsequently growth rates slow down

(Daget et al., 1965). At least in some species sexual

maturity may be reached in one year (Svensson,

1933). The lungs of bichirs are paired and well

developed and vascularized and atmospheric air

is regularly taken in for respiration. Air uptake

may be realized in two different ways: inhaling

air via the mouth, or via the spiracles (Budgett,

1900; Bartsch, 1997).

Remarks. The oldest available family group name

for polypterids dates back to Bonaparte (1835: 8)

who listed “Subfamilia 36. Polypterini” in his

‘Prodromus Systematis Ichthyologiae’.

Genus Erpetoichthys Smith, 1865

Erpetoichthys Smith, 1865a: 2.

Calamichthys Smith, 1866a: 113.

Calamoichthys Smith, 1866a: 112.

Type species. Erpetoichthys calabaricus Smith, 1865.

Diagnosis. Erpetoichthys is distinguished from

all other members of the family by absence

of pelvic fin and subopercle (vs. presence in

Polypterus), body depth 2.9-5.2 % SL (vs. 7.0-16.5

in Polypterus), 109-115 vertebrae (vs. fewer than

67 in Polypterus), short head (7.2-10.5 % SL vs.

14.4-26.8 in Polypterus), and 16-21 pectoral fin-

rays (vs. 24-48 in Polypterus).

Descriptive synopsis. Body greatly elongated,

anguilliform with 109-115 vertebrae and 102-115

scales in lateral series. Sexual dimorphism in anal

Ichthyol. Explor. Freshwaters, IEF-1094

fin much pronounced: males with 11-14 (mean

13) and female with 8-13 (mean 10) anal-fin rays;

each ray in mature males widened along its an-

teroposterior axis. For meristic and morphometric

data refer to Tables 1-2.

Etymology. Erpetoichthys is derived from the

Greek ρπετ)+, reptile or snake; and θς, fish.

Remarks. Confusion about the valid name of

the genus arose from multiple descriptions by

Smith (1865a-b; 1866a-c) and from a subsequent

change of the generic name by Smith one year later

(1866a, c), because he erroneously considered the

original name Erpetoichthys to be preoccupied. De-

tails on this nomenclatural issue were discussed

by Swinney & Heppell (1982) and Rizzato &

Bockmann (2017) with contradicting results. We

follow Swinney & Heppell’s (1982) view and

consider the name Erpetoichthys calabaricus to be

available from Smith (1865a). This is in contrast

to the recent conclusion by Rizzato & Bockmann

(2017) which rests solely on their interpretation of

Art. 8.1.1 of the Internacional Code of Zoological

Nomenclature (ICZN, 1999; hereafter treated as

“the Code”). Rizzato & Bockmann (2017) argued

that publication of Smith’s (1865a) name in the

newspaper ‘Daily Review’ was not “issued for

the purpose of providing a public and permanent

scientific record” as the Art. 8.1.1. requires for a

name to be available. The authors argue in detail,

that “First, and most importantly, the report was

clearly intended solely to publicize a scientific

breakthrough for the general public of Edinburgh,

not to name the fish according to formal scientific

standards.” While Rizzatto & Bockmann (2017)

present this argument as a fact, we consider this

to be speculation, as the intention of the author

is unknowable. Rizzatto & Bockmann’s (2017)

main conclusion that Smith’s (1865a) name is not

available centers very much around the intention

of a given author and they mention ‘intention’,

‘intend’, ‘intentionally’, ‘unintentionally’ 21 times

in their lengthy paper. However, according to

the Code it is not the intention that is decisive.

While it cannot be objectively decided whether

Smith’s (1865a) first publication of the name was

“issued for the purpose of providing a public

and permanent scientific record”, we argue that

publication of the name Erpetoichthys calabaricus in

the Daily Review in 1865, which is still available

today, in conjunction with a diagnosis, makes

this name available, as concluded previously by

Swinney & Heppell (1982). We therefore reject

Rizzatto & Bockmann’s (2017) conclusion and

retain Erpetoichthys calabaricus as the valid name

for the rope eel. Furthermore, following Rizzatto

& Bockmann’s (2017) rationale would also greatly

destabilize nomenclature generally, as numerous

nomenclatural acts in the 1800s and early 1900s

were published in minutes and proceedings of

scientific sessions before the more comprehensive,

‘actual’ paper was published. Fricke et al. (2018)

also decided not follow the conclusions of Rizzato

& Bockmann (2018).

Erpetoichthys calabaricus Smith, 1865

(Figs. 3-5; Tables 1-2)

Erpetoichthys calabaricus Smith, 1865a: 2.

Erpetoichthys robbianus Smith, 1865b: 2.

Polypterus erpetoideus Smith, 1865a: 2.

Material examined. 32 specimens. Ouém é Basi n:

RMNH 24896, 1, 187 mm SL; Benin: Cotonou, L. B.

Holthuis & H. Hoestland, 1963. niger Delta: RMNH

10327, 1, 313 mm SL; Nigeria: Warri, Diergaarde Rot-

terdam, 20 Nov 1918. – RMNH 8858, 2, 293-318 mm

SL; Nigeria: Warri, J. Büttikofer, Oct 1912. – BMNH

1977.11.8.1-4, 4, 262-300 mm SL; Nigeria: Lagos: En-

ergo project site near Lagos, D. Thomas. – MNHN

2008-2103, 9, 252-307 mm SL; Nigeria: Port Harcourt

[market]; T. Roberts, 5 Nov 1987. CrOss river Basin:

MNHN 0000-4599, 2, 223-301 mm SL; Nigeria: Old

Calabar, J. A. Smith, before 1867. – NMW 22831, 1,

147 mm SL; Nigeria: Old Calabar, 1874. – NMW 22832,

1, 162 mm SL; Nigeria: Old Calabar, 1874. – NMW 50282,

1, 343 mm SL; Nigeria: Old Calabar. – NMW 63194, 1,

205 mm SL; Nigeria: Old Calabar, 1874. – NMW 63195,

2, 247-320 mm SL; Nigeria: Old Calabar, 1877. limBe

river Basin: MNHN 1900-0218, 1, 180 mm SL; Cam-

eroon: Victoria, Lennier. sanaga river Basin: MNHN

1978-0732, 1, 313 mm SL; Cameroon: Sanaga River at

Mouanko, Depierre, 1978. – MRAC 73-002-P-0001-0003,

3, 271-286 mm SL; Cameroon: Sanaga River at Edea

[below waterfalls], D. F. E. Thys van den Audenaerde,

15-16 Oct 1964. – MRAC 75-005-P-4758, 1, 305 mm SL;

Cameroon: km 5 on the road Douala to Edea, D. F. E.

Thys van den Audenaerde, 21 Oct 1966. WOuri river

Basin: MNHN 1928-0080, 1, 321 mm SL; Cameroun:

Vouri [= Wouri] River at Nono, Monod.

Additional material. Ouémé Basin: DMM IE/10401, 5,

Benin: Zou: Lokoli swamp forest, 7°03'40" N 2°15'32" E;

T. Moritz, 16 Jan 2005. iguiDi river Basin: DMM

IE/14378, 2, Benin: Iguidi River at Igolo, 6°39'18" N

2°42'43" E; T. Moritz & V. von Vietinghoff, 11 May 2005.

– DMM IE/14388, 1, Benin: Iguidi River at Tchakou,

Moritz & Britz: Revision of Polypterus

Fig. 3. Erpetoichthys calabaricus, NMW 63195:1, 320 mm SL, male, non-type, Nigeria: Old Calabar [type locality];

1877.

Fig. 4. Erpetoichthys calabaricus, a-b, ~280 mm SL; Nigeria: aquarium import; c-d, ~180 mm SL; Benin: Ouémé

Basin: Lokoli swamp forest.

6°28'27" N 2°42'48" E; T. Moritz, 22 Mar 2007. CrOss

river Basin: MNHN 1988-0253, 1, Nigeria, Cross River

at Uyo, King, 1987.

Diagnosis. Same as presented for the genus.

Descriptive synopsis. Meristic and morpho-

metric data in Tables 1-2. Body anguilliform

(body depth 18-34 times in SL); body circular

in cross section along most of body; but later-

ally compressed in posterior most part towards

Ichthyol. Explor. Freshwaters, IEF-1094

caudal peduncle. Mouth subterminal with upper

jaw strongly projecting beyond lower jaw; head

only slightly depressed. Maximum observed size

343 mm SL (355 mm TL). Occasionally reported

maximum sizes of up to 900 mm (e. g. Terofal,

1970; Gosse, 1984) are erroneous.

Coloration. In life: dorsal half of body brown-

yellowish with borders of vertical scale rows

darker; no additional markings (Fig. 4). Ventral

half of body yellowish-orange. No clear border

between upper and lower half of flank colora-

tion. Head coloration same as that on body, but

nasal tentacles lighter; suborbital stripe absent.

Table 2. Meristic characters of Erpetoichthys calabaricus. Numbers in brackets indicate number of specimens with

the respective value.

all material

Dorsal-fin spines 9 (8), 10 (11), 11 (9)

Dorsal- and caudal-fin rays 10 (1), 12 (2), 13 (7), 14 (10), 15 (6), 16 (1)

Pectoral-fin rays 16 (3), 17 (3), 18 (6), 19 (10), 20 (4), 21 (1)

Anal-fin rays 8 (3), 9 (4), 10 (3), 11 (6), 12 (4), 13 (4), 14 (3)

Scales in longitudinal series 102 (1), 104 (1), 105 (1), 106 (3), 107 (5), 108 (1), 109 (8), 110 (4), 111 (1), 112 (1), 113 (1),

114 (1)

Scales around body 27 (3), 28 (3), 29 (5), 30 (10), 31 (5), 32 (1), 33 (1)

Pre-dorsal scales 44 (1), 48 (1), 49 (5), 50 (2), 51 (5), 52 (2), 53 (4), 54 (2), 55 (2), 56 (1), 57 (1), 58 (1), 59 (1)

Total number of vertebrae 109 (1), 110 (1), 112 (2), 113 (1), 115 (1)

Table 1. Morphometric characters of Erpetoichthys calabaricus. SD: standard deviation

range mean SD n

Standard length [mm] 147-343 266.5 51.2 28

Total length [mm] 171-355 281.2 47.5 27

In percent of standard length

Body depth 2.9-5.2 4.2 0.7 28

Body width 3.5-5.5 4.6 0.5 28

Head length 7.2-10.5 8.1 0.7 28

Pre-dorsal length 41.0-54.2 47.5 3.1 28

Dorsal-fin length 34.9-53.9 47.8 4.0 28

Pectoral to dorsal fin 28.6-40.7 34.6 2.8 26

Pre-pectoral length 7.8-10.7 8.8 0.7 28

Pectoral-fin extension 10.6-19.3 12.8 1.6 26

Inter-pectoral width 2.8-4.1 3.6 0.3 28

Pectoral-fin base width 0.8-1.5 1.2 0.2 28

Pre-anal length 93.0-95.1 94.1 0.5 28

Anal-fin ray length 3.6-5.5 4.6 0.5 27

Anal-fin base length 1.2-3.6 2.8 0.5 27

Caudal-peduncle length 0.8-1.6 1.1 0.2 27

In percent of head length

Head width 49.1-68.0 58.5 5.7 28

Interorbital width 21.6-28.5 25.4 1.8 28

Nostril distance 11.2-19.6 15.3 2.2 28

Snout length 21.9-26.9 24.8 1.3 28

Eye diameter 8.8-16.3 12.0 1.6 28

Postorbital length 60.4-65.2 63.3 1.2 28

Gular length 54.5-63.3 59.0 2.1 28

Length of first spine 8.8-22.5 17.0 2.9 28

Length of second spine 6.7-25.9 17.6 3.9 28

Width : length of first spine 24.3-51.2 35.2 7.1 28

Length of second : first spine 70.2-143.2 103.9 19.0 28

Moritz & Britz: Revision of Polypterus

Iris orange, brownish or grey; lips of upper and

lower jaw yellowish-orange without any mark-

ings. Pectoral fin yellowish-orange, at its proximal

part with black blotch extending onto distalmost

part of pectoral-fin base, leaving most of pectoral-

fin base without markings. Soft part of dorsal fin

and caudal fin brown, grey or olive with yellow-

orange fin membranes. Dorsal-fin spines brown,

grey or olive, their distal part orange; membrane

of finlets transparent or slightly yellowish with

only very few small dark spots.

In preservative: dorsal half of body and head

brown or brownish-grey (Fig. 3); ventral half of

body and head including lips and nasal tenta-

cles pale beige or brownish, sometimes slightly

orange-brown.

Distribution. From the Ouémé Basin in Benin,

across the Niger Delta in Nigeria to the Sanaga

River in Cameroon along West Africa’s coastal

basins (Fig. 4). A single record from the Chiloango

River (= Rio Hi) in the Cabinda region of Angola

mentioned in Boulenger (1909: 18) seems ques-

tionable; the species has not been reported since

from that area (Boulenger, 1912; Pellegrin, 1928;

Daget & Stauch, 1968).

Biology. Prefers small streams and swamps

(Smith, 1866a). Feeds on terrestrial insects, e. g.

termites (Smith, 1866c), insect larvae and aquatic

invertebrates. Reproduction in captivity and

early development were described by Britz &

Bartsch (1998).

Etymology. Smith (1865a) used calabaricus to refer

to “. . . the locality [Old Calabar, Nigeria] where

it was discovered”.

Remarks. Originally two syntypes were present,

but both were lost (see Swinney & Heppell, 1982).

The original description was based on two poorly

preserved specimens from Old Calabar, Calabar

River and adjacent water bodies, Nigeria, col-

lected by A. Robb on an unspecified date. There

are two specimens in the Paris Museum, MNHN

0000-4599, which are labelled as “TYPES”, and

listed as paratypes in the museum’s on-line

collection database (https://science.mnhn.fr/

30°N

20°N

10°N

0°

10°S

30°N

20°N

10°N

0°

10°S

10°W 10°E 20°E 30°E0°

Fig. 5. Records of Erpetoichthys calabaricus. , type locality; , verified records; , other records; , question-

able records.

Ichthyol. Explor. Freshwaters, IEF-1094

–

ı ı ı ı ı ı ı ı ı ı ı ı ı ı

P.ans P.bic P.con P.end P.del P.mok P.orn P.pal P.pol P.ret P.sen P.teu P.wek

ı ı ı ı ı ı ı ı ı ı ı ı ı ı

DSScLScB

Fig. 6. Box-and-whisker plots of selected meristic data of Polypterus species. DS, number of dorsal spines;

ScL, number of scales in lateral series; ScB, number of scales around body; ScpD, number of pre-dorsal scales;

ScpP, number of pre-pelvic scales; P.ans, P. ansorgii (n = 7); P.bic, P. bichir (n = 139); P.con, P. congicus (n = 66);

P.end, P. endlicherii (n = 64); P.del, P. delhezi (n = 44); P.mok, P. mokelembembe (n = 26); P.orn, P. ornatipinnis (n = 63);

P.pal, P. palmas (n = 122); P.pol, P. polli (n = 85); P.ret, P. retropinnis (n = 46); P.sen, P. senegalus (n = 226);

P.teu, P. teugelsi (n = 4); P.wek, P. weeksii (n = 45).

institution/mnhn/collection/ic/item/search/

form). Smith sent these specimens to the MNHN

and Duméril (1870) used them for his account of

the species in his ‘Histoire naturelle des poissons’.

Bertin (1940) finally listed the MNHN specimens

as paratypes referring to the redescription of

Duméril (1870). Although the specimens were sent

by Smith and come from the type locality they are

not part of the original type series. Smith (1865a)

had only two males, for his species description,

while the two specimens in the MNHN are male

and female; furthermore, the MNHN collection

database provides 1867 as the collection date for

these specimens, thus two years after the descrip-

tion of the species.

Polypterus erpetoideus was proposed as another

name for the species by Smith and reported in the

same newspaper article which served as original

description. This name was not used subsequently

and Swinney & Heppell (1982), as first revisers,

Moritz & Britz: Revision of Polypterus

Ichthyol. Explor. Freshwaters, IEF-1094

–

ı ı ı ı ı ı ı ı ı ı ı ı ı ı

P.ans P.bic P.con P.end P.del P.mok P.orn P.pal P.pol P.ret P.sen P.teu P.wek

ı ı ı ı ı ı ı ı ı ı ı ı ı ı

ScpDScpP

Fig. 6. (continued).

selected Erpetoichthys calabaricus as the valid name

for the taxon.

Smith’s (1865b) description of Erpetoichthys

robbianus was based on specimens with a small,

narrower anal fin, which is the condition in fe-

males of the sexually dimorphic anal fin (Traquair,

1866a-b; Smith, 1866a-c) in polypterids. Follow-

ing Swinney & Heppell (1982) NMSZ 1867.18.1;

NMSZ 1979.006.002 and BMNH 1908.1.27.2 pre-

sumably are part of the type series of E robbianus.

Herman et al. (1990) additionally listed NMSZ

1885.052 as part of this type series.

Genus Polypterus Lacèpede, 1803

Polyptere Geoffroy [Saint Hilaire], 1802a: 12, Plate

Polypterus Lacépède, 1803: 340.

Type species. Polypterus bichir (Geoffroy, 1802)

by monotypy.

Diagnosis. Distinguished from Erpetoichthys by

presence of pelvic fin, presence of subopercle,

more pectoral-fin rays (24-48 vs. 16-21) and

comparatively shorter body (body depth 6-12

times in SL vs. 18-29 times) with fewer vertebrae

(67 or fewer vs. 109-115).

Descriptive synopsis. Body elongated to highly

elongated and eel-like, circular in cross section,

but laterally compressed in the postabdominal

part of the body. Polypterus is characterized by

50-70 scales in the lateral series, 10-38 pre-dorsal

scales, 31-54 scales around the body, 34-53 pre-

pelvic scales, 5-18 dorsal-fin spines, 13-24 soft

rays in confluent soft dorsal plus caudal fin, 24-

48 pectoral-fin rays; and pelvic fin present, with

7-17 rays. Figures 6 and 7 summarize selected

meristic and morphometric characters for the

genus. Sexual dimorphism in number of anal-fin

rays less pronounced than in Erpetoichthys: males

on average with one additional ray compared

to females; equally conspicuous enlargement of

anal fin in mature males through antero-posterior

widening of individual anal-fin rays.

Biology. See remarks for Polypteridae.

–

–10

–

ı ı ı ı ı ı ı ı ı ı ı ı ı ı

P.ans P.bic P.con P.end P.del P.mok P.orn P.pal P.pol P.ret P.sen P.teu P.wek

ı ı ı ı ı ı ı ı ı ı ı ı ı ı

preDLdistPD

–

DFL

Fig. 7. Box-and-whisker plots for selected morphometric characters of Polypterus species. preDL, pre-dorsal

length; DFL, dorsal-fin length; distPD, distance between end of pectoral fin and origin of dorsal fin; HL, head

length; IOW, inter-orbital width; SnL, snout length; for other abbreviations and number of specimens see Figure 6.

Etymology. Polypterus is derived from the Greek

πλς – many and πτερ)+ – wing, apparently re-

ferring to the anterior part of the dorsal fin which

comprises multiple separate finlets.

Remarks. The genus name was originally spelled

Polyptère by Geoffroy (1802a). Lacépède (1803)

used this original name but also provided a

Latinized version. Only a few years later also

Geoffroy (1809) used both names, the original

French spelling and the Latinised version in his

‘Histoire naturelle des Poissons du Nil’.

Eschmeyer (1998) originally listed the type

species as “Polypterus bichir Geoffroy St. Hilaire”

but changed it in the on-line edition of the Catalog

of Fishes (Fricke et al., 2018) to “Polypterus bichir

Lacépède, 1803”, arguing that the generic name

was not Latinised in Geoffroy’s (1802a) descrip-

tion. Holly (1933) had come to this conclusion and

Schäfer (2004) shared this same view. Likewise,

Shaw (1804) regarded Geoffroy’s (1802a) name

as not valid, and even introduced a new species-

name, i. e. P. niloticus, but using at the same time

the Latinised genus of the name given by Geof-

Moritz & Britz: Revision of Polypterus

Ichthyol. Explor. Freshwaters, IEF-1094

Fig. 7. (continued).

–

ı ı ı ı ı ı ı ı ı ı ı ı ı ı

P.ans P.bic P.con P.end P.del P.mok P.orn P.pal P.pol P.ret P.sen P.teu P.wek

ı ı ı ı ı ı ı ı ı ı ı ı ı ı

HLSnL

–

IOW

froy. The argumentation of the above mentioned

authors, however, is not in congruence with Art.

11.3 of the Code, which clearly states that a name

may be a word in or derived from any language.

Thus Polyptere (without apostrophe following

Arts. 27 and 32.5.2 of the Code) Geoffroy is an

available name and a senior synonym of Polypterus

Lacépède. However, because Polyptere has not

been used as a valid genus name since 1899 (Art.

23.9.1.1 of the Code) we declare Polyptere Geof-

froy, 1802 a nomen oblitum under Art. 23.9.2 of the

Code and the name Polypterus Lacépède a nomen

protectum because the latter has been used in at

least 25 works in the last 50 years by at least 10 dif-

ferent authors (Art. 23.9.1.2 of the Code) (Banister

& Bailey, 1979; Daget & Desoutter, 1983; Gosse,

1984, 1988, 1990, 2003; Bailey, 1994; Hanssens

et al., 1995; Bartsch & Britz, 1996; Seegers, 1996;

Bartsch, 1997; Britz & Bartsch, 1998, 2003; Britz

& Johnson, 2003; Britz, 2004; Lalèyè et al., 2004;

Schäfer, 2004; Poplin & Dutheil, 2005; Schliewen

& Schäfer, 2006; Schugardt & Kirschbaum, 2006;

Claeson et al., 2007; Claeson & Hagadorn, 2008;

Suzuki et al., 2010; Cuervo et al., 2012; Trape, 2013;

Near et al., 2014; Neumann et al., 2016; Grandstaff

et al., 2017; Moritz, 2017).

Thirteen valid species of Polypterus are herein

recognised. Morphologically two groups can be

Fig. 9. Changes in head shape during growth in Poly-

pterus endlicherii. a, DMM IE/10399, 102 mm SL; Benin:

Pendjari National Park; b, DMM IE/10393, 150 mm SL;

Benin: Pendjari National Park; c, BMNH 1949.10.20.1,

272 mm SL; Ghana: Volta Basin.

Moritz & Britz: Revision of Polypterus

121 2

Fig. 8. Anteriormost scale row running continuously from dorsal to ventral mid-line is a, third row in Polypterus

ansorgii, and b, second row in P. senegalus.

distinguished: the “large” species group (P. ansor-

gii, P. bichir, P. congicus and P. endlicherii), and the

“small” species group, including all the remaining

members of the genus. Available molecular data

(Suzuki et al., 2010; Near et al., 2014) support the

monophyly of the “large” species, a taxon we call

herein the Polypterus bichir group. The “small”

species apparently do not form a monophyletic

group. The typical character states of the P. bichir

group seem to be rather derived conditions, e. g.

high number of dorsal-fin spines, low number

or pre-dorsal scales (Fig. 6), the third scale row

being the first to continue from dorsal to ventral

midline (vs. second scale row being the first to

continue all the way to the ventral midline; Fig. 8).

Our taxonomic study offers no obvious character

evidence that would support additional clades

among the “small” polypterid species group sup-

ported by molecular data.

Accurate identification of polypterids is often

complicated due to the similarity in their general

appearance, but also because of changes in body

shape during growth. One example is the project-

ing lower jaw of specimens of Polypterus bichir,

P. congicus and P. endlicherii. This character is often

used in identification keys (e. g. Boulenger, 1898;

Pellegrin, 1923a; Holly, 1933; Poll, 1941a; Gosse,

1990, 2003). In juveniles of these species, however,

jaws are still equal and the mouth is in a terminal

position. This has occasionally resulted in the er-

roneous identifications of juvenile P. endlicherii or

P. bichir as P. ansorgii in collections (e. g. AMNH

215310, USNM 339728) or in publications (e. g., La-

lèyè et al., 2004). Polypterus ansorgii is the smallest

species of the P. bichir group with jaws remaining

almost equal in size throughout life. In general

the head shape of members of the P. bichir group

changes during growth becoming flatter and thus

wider in appearance; this is most pronounced

in P. endlicherii (Fig. 9). A similar flattening of

the head can be seen to a smaller extent in large

specimens of P. weeksii.

Furthermore, the finlet membranes attached

to each dorsal-fin spine are supported by second

order dorsal-fin rays (Fig. 10a), the number of

which is only of limited, if any, diagnostic value

because during growth finlets acquire more of

these secondary rays (Fig. 10b; Sewertzoff, 1924).

As a result, adults of large species of the P. bichir

group seem to have more of these second order

a b

Fig. 10. Dorsal-fin spines and secondary rays in live Polypterus delhezi, lateral view. a, juvenile of 72 mm SL; b,

adult 240 mm SL.

dorsal-finlet rays than their juveniles or than

adults of other species.

The position of the first dorsal-fin spine in

relation to the posterior margin of the pectoral fin

is often used (e. g. Gosse, 1990, 2003) to distinguish

between the “large” and “small” species, i. e. the

P. bichir group and the remaining Polypterus spe-

cies. Although helpful to identify certain species,

this character does not allow a clear distinction be-

tween the two groups: occasionally in specimens

of P. senegalus the first dorsal-fin spine is situated

directly above the posterior tip of the pectoral fin

and some P. bichir specimens show a clear gap

between the vertical through the posterior margin

of the adducted pectoral fin and that of the base

of the first dorsal-fin spine (Fig. 8). Unusual in

this regard is P. delhezi which usually has its first

dorsal-fin spine anterior to the posterior margin of

the pectoral fin, a condition typical of the P. bichir

group, although other characters are consistent

with its inclusion among the “small” Polypterus

species. The commonly used number of dorsal-fin

spines and number of scales to characterize species

are often overlapping between species, but there

are still a number of useful meristic and morpho-

metric characters to distinguish poly pterid species

(Fig. 6-7). In general, certain polypterid species

have a somewhat similar morphology and are

best distinguished by differences in coloration.

Polypterus ansorgii Boulenger, 1910

(Figs. 11-13, Tables 3-4)

Polypterus ansorgii Boulenger, 1910: 424.

Material examined. 7 specimens. type speCimens:

BMNH 1910.9.13.4, lectotype (Fig. 11; present designa-

tion), 169 mm SL; likely juvenile female, Guinea-Bissau:

Corobal River at Tchitoli, W. J. Ansorge, Jun 1909. –

NMW 63252: 1-2, 2, paralectotypes, 147-160 mm SL;

collected with the lectotype. géBa river Basin: MRAC

73-005-P-0031, 1, 180 mm SL; Senegal: Geba River Basin:

Kanyanga River at Kounkane, 12°55' N 14°06' W; D. F.

E. Thys van den Audenaerde, 6 Apr 1966. – MRAC

73-005-P-0032-0033, 2, 179-210 mm SL; Senegal: Geba

River Basin: Kanyanga River at Kounkane, 12°55' N

14°06' W; D. F. E. Thys van den Audenaerde, 8 Apr

1966. CasamanCe river Basin: MRAC 73-005-P-0030, 1,

210 mm SL; Senegal: Casamance River at Kolda, 12°53' N

14°57' W; D. F. E. Thys van den Audenaerde, 8 Apr 1966.

Diagnosis. Distinguished from all Polypterus spe-

cies, except P. bichir, P. congicus and P. endlicherii

by 13-15 dorsal finlets (vs. 5-12) and the second

dorsal scale row not reaching ventral midline

(vs. reaching ventral midline). Distinguished

from P. congicus and P. endlicherii by smaller

interorbital width (15.7-18.5 % HL vs. 17.9-

27.4 %) and by coloration consisting of more or

less regular, rectangular lateral blotches usually

not confluent with dorsal saddle blotches (vs.

no separate regular rectangular lateral blotches,

but series of bars formed by confluence of dorsal

blotches with lateral blotches in P. congicus and

with lateral blotches and ventrolateral markings

in P. endlicherii). Polypterus ansorgii differs from

P. bichir by fewer scales in lateral series (54-56

vs. 55-70), fewer scales around body (43-45 vs.

43-54) and smaller adult size (maximum recorded

size 313 mm SL vs. 750); in specimens between

150 and 200 mm SL, external gills usually com-

pletely reduced in P. ansorgii (vs. present in most

specimens of P. bichir). Specimens smaller than

147 mm SL of P. ansorgii have not been available

for this study and it remains unclear, whether

it would be possible to distinguish them from

equally small specimens of P. bichir based on

external characters.

Ichthyol. Explor. Freshwaters, IEF-1094

Descriptive synopsis. Meristic and morphomet-

ric data in Tables 3-4. Body moderately elongated.

Jaws terminal, in larger specimens (> 200 mm

SL) lower jaw slightly projecting beyond upper

jaw. Head flattened. Likely the smallest species

among the Polypterus bichir group with the largest

specimens in collections measuring 210 mm SL

(246 mm TL), and unpreserved aquarium speci-

men reaching 313 mm SL (371 mm TL).

Table 3. Morphometric characters of Polypterus ansorgii. Range, mean and standard deviation (SD) include values

of lectotype. Negative values under ‘Pectoral to dorsal fin’ refer to dorsal-fin origin in front of pectoral-fin end.

lectotype range mean SD n

Standard length [mm] 169.0 147-210 178.0 22.1 7

Total length [mm] 205.0 178-246 211.3 21.3 7

In percent of standard length

Body depth 11.6 10.8-12.3 11.6 0.5 7

Body width 12.9 11.2-12.9 12.4 0.6 7

Head length 23.3 22.6-24.9 23.5 0.8 7

Pre-dorsal length 30.1 30.1-33.5 31.9 1.2 7

Dorsal-fin length 59.9 52.0-59.9 56.1 2.6 7

Pectoral to dorsal fin -6.0 -6.3--3.1 -4.5 1.2 7

Pre-pectoral length 22.9 22.9-25.0 23.8 0.7 7

Pectoral-fin extension 35.7 35.4-38.2 37.0 1.1 7

Inter-pectoral width 8.6 7.7-9.6 8.9 0.6 7

Pectoral-fin base width 3.3 3.3-3.6 3.5 0.1 7

Pre-pelvic length 70.2 69.8-72.1 71.1 0.9 7

Pre-anal length 85.9 84.1-86.0 85.3 0.8 7

Anal-fin ray length 14.2 12.3-14.6 13.5 0.8 7

Anal-fin base length 5.0 4.5-5.6 5.2 0.4 7

Caudal-peduncle length 3.6 2.8-3.7 3.3 0.3 7

In percent of head length

Head width 56.0 49.8-62.3 55.2 4.9 7

Interorbital width 17.3 15.7-18.5 17.4 0.9 7

Nostril distance 12.2 10.6-12.2 11.7 0.6 7

Snout length 19.5 17.2-21.2 19.5 1.6 7

Eye diameter 12.6 11.1-13.5 12.3 0.9 7

Postorbital length 67.5 65.1-68.5 66.4 1.2 7

Gular length 70.3 53.9-70.3 59.5 5.2 7

Length of first spine 19.7 19.4-22.5 21.0 1.1 7

Length of second spine 23.8 23.1-25.5 23.9 0.8 7

Width : length of first spine 23.1 16.7-23.1 19.7 2.2 7

Length of second : first spine 120.7 103.3-122.8 114.3 7.2 7

Table 4. Meristic characters of Polypterus ansorgii. Numbers in brackets indicate number of specimens with the

respective value. ‘All material’ includes values of lectotype.

lectotype all material

Dorsal-fin spines 15 13 (5), 14 (1), 15 (1)

Dorsal- and caudal-fin rays 17 17 (2), 19 (5)

Pectoral-fin rays 39 35 (1), 37 (1), 39 (2), 40 (1), 42 (2)

Pelvic-fin rays 10 10 (2), 11 (3), 12 (2)

Anal-fin rays 11 11 (2), 12 (2), 13 (2), 14 (1)

Scales in longitudinal series 56 54 (1), 55 (4), 56 (2)

Scales around body 44 43 (1), 44 (4), 45 (2)

Pre-dorsal scales 11 11 (1), 12 (2), 13 (4)

Pre-pelvic scales 40 40 (1), 41 (5), 42 (1)

Total number of vertebrae 57 57 (1)

Moritz & Britz: Revision of Polypterus

Coloration. In life (based on photographs of two

imported specimens of ca. 300 mm SL): dorsal

half of body grey or brown with dark grey to dark

brown dorsal saddle blotches; along flanks dark,

more or less regular, rectangular lateral blotches in

longitudinal series; separated from dorsal bars by

narrow light stripe (Fig. 12). Ventral half of body

whitish to cream with ventrolateral markings

expressed as interrupted dark line below lateral

blotches. Head dark grey dorsally, becoming

lighter laterally and whitish ventrally; irregular

dark spots all over head. Iris light grey with dark

grey irregular pattern. Coloration of upper lips

not differing from dorsal head coloration; lower

lips light beige with large dark spots. Pectoral,

pelvic and confluent dorsal-caudal fin yellowish;

small number of dark spots in pelvic and anal

fins, spots more numerous in soft part of dorsal

fin and in caudal fin; spots arranged in regular

rows on pectoral fin. Dorsal-fin spines dark grey

on anterior face, more yellowish on lateral and

posterior faces; finlet membrane transparent to

slightly greyish.

In preservative: all studied preserved speci-

mens considerably depigmented: no blotches or

spots on lower jaw, head or lower half of flanks.

Dorsal saddle blotches and rectangular blotches

along flank, however, appearing more prominent

than in life.

Distribution. Known only from three river ba-

sins in Guinea-Bissau and the Senegal: Corobal

River, Géba River and Casamance River (Fig. 13).

Records from eastern Niger basin (MRAC 92-014-

P-0001-0002) are based on confusion with P. bichir

(see below). Daget’s (1954: 57) record of P. ansorgii

from the Upper Niger basin was subsequently

regarded by Daget & Iltis (1965) as based on an

‘atypical P. bichir lapradii’.

Biology. At least in captivity not different in

behaviour from other species of P. bichir-complex:

voracious predator, predominantly active during

night.

Etymology. Named after Dr. W. J. Ansorge who

collected type specimens.

Remarks. Three specimens were mentioned in

the original description. They are syntypes and are

currently housed in the collections of BMNH and

NMW. We hereby designate BMNH 1910.9.13.4

(Fig. 11) as the lectotype of P. ansorgii.

Fig. 11. Polypterus ansorgii, BMNH 1910.9.13.4, 169 mm SL, juvenile or female, lectotype (present designation);

Guinea Bissau: Corobal River at Tchitoli; W. J. Ansorge; Jun 1909.

Ichthyol. Explor. Freshwaters, IEF-1094

Previous confusion of P. ansorgii with other

Polypterus species was probably caused by the sig-

nificant variation in coloration in P. bichir across

its range, and by changes in head shape during

growth in large Polypterus species. The jaws are

of equal length in juveniles in those species that

have a projecting lower jaw in adults, a condition,

which may have led to confusion with P. ansorgii.

Several keys list the equal length of the jaws as

a distinguishing character of P. ansorgii from the

other large species (e. g. Daget & Iltis, 1965). Ad-

ditional records of P. ansorgii from Lake Kainji,

Ogun River (AMNH 215310, USNM 339728)

and Ouémé River (Lalèyè et al., 2004) represent

misidentifications.

Fig. 12. Polypterus ansorgii, aquarium import from Guinea Bissau. a, 313 mm SL, male with light coloration; b, same

specimen with darker coloration; c, detail of head.

Moritz & Britz: Revision of Polypterus

Polypterus bichir (Geoffroy, 1802)

(Figs. 14-20, Tables 5-6)

Polyptere bichir Geoffroy [Saint-Hilaire], 1802a: 98.

Polypterus bichir katangae Poll, 1941a: 145.

Polypterus bichir lapradei Steindachner, 1869: 103.

Polypterus niloticus Shaw, 1804: 122.

Material examined. 148 specimens. MNHN 0000-5761,

lectotype (Fig. 14), 585 mm SL; Egypt: Nile River, E.

Geoffroy Saint-Hilaire, 1799. – MNHN 0000-5806, 1,

paralectotype, 549 mm SL; dry mounted specimen,

Egypt: Nile River, E. Geoffroy Saint-Hilaire, 1799. sen-

egal: NMW 63244, 1, 464 mm SL; syntype of P. lapradei,

Senegal: Taoué close to Richar-Toll [= Touey-Marigot],

16°31' N 15°41' W; F. Steindachner, Nov 1868 [but jar

labelled with March 1869, likely referring to date of

registration] (Fig. 15). – NMW 63242, 1, 182 mm SL;

syntype of P. lapradei, Senegal: Podor, ca. 16°39' N

14°57' W; F. Steindachner, Nov 1868 [but jar labelled

with March 1869, likely referring to date of registration].

– NMW 63243:1-2, 2, 166-190 mm SL; syntypes of

P. lapradei, Senegal: Dagana, ca. 16°31' N 14°57' W; F.

Steindachner, Nov 1868 [but jar labelled with March

1869, likely referring to date of registration]. – BMNH

1900.6.28.1, 1, 536 mm SL; Senegal: St. Louis, M. Delhez.

– BMNH 1900.6.28.2-3, 2, 625-675 mm SL; Senegal:

Kaedi, M. Delhez. – BMNH 1900.6.28.4-7, 4, 284-364 mm

SL; Senegal: Kaedi, M. Delhez. – BMNH 1900.6.28.9, 1,

334 mm SL; Senegal: Kaedi, M. Delhez. – MRAC 140104,

1, 308 mm SL; Senegal: Kaedi, M. Delhez, around 1900.

– MRAC 73-005-P-0024, 1, 226 mm SL; Senegal: Djeuss

[St. Louis] River at Bouben, D. F. E. Thys van den

Audenaerde, 8 Mar 1966. – MRAC 73-005-P-0027-0028,

2, 377-399 mm SL; Senegal: Lampsar River [in Senegal

River Delta] at Ross Bethio, D. F. E. Thys van den

Audenaerde, 10 Mar 1966. – MRAC 73-005-P-0029, 1,

494 mm SL; Senegal: Casamance River at Kolda, D. F.

E. Thys van den Audenaerde, 3 Apr 1966. – NMW 63053,

1, 750 mm SL; Senegal, Steindachner. – MNHN 1907-

0250, 1, 338 mm SL; Senegal, Gruvel. gamBia river

Basin: BMNH 1901.7.17.1, 1, 387 mm SL; Gambia, J. S.

Budgett. – BMNH 1905.11.13.10, 1, 326 mm SL; Gambia,

Capt. Vipan. – MNHN 1980-1603, 1, 293 mm SL; Sen-

egal: Gambia River at Wassadou, D. Paugy. geBa

river: BMNH 1912.4.1.2-3, 2, 525-630 mm SL; Guinea-

Bissau: Geba River at Bafata, W. Ansorge. vOlta river

Basin: MRAC 140927-140929, 2, 198-213 mm SL; Bur-

kina Faso: Kou River [tributary of Mouhoun], 4 Jun

1964, B. Roman. – MRAC 143517-143518, 2, 194-220 mm

SL; Burkina Faso: north of Bobo-Dioulasso, B. Roman.

niger river anD triButaries: BMNH 1884.6.9.9-10, 2,

510-517 mm SL; Nigeria: Niger River, Esq. W. Forbes.

– BMNH 1884.6.9.14-18, 5, 257-330 mm SL; Nigeria:

Niger River, Esq. W. Forbes. – BMNH 1907.5.3.1, 259 mm

SL; Nigeria: Benue River north of Ibi, Capt. Vipan. –

BMNH 1928.7.3.1, 1, 255 mm SL; Nigeria: Kiyawa

30°N

20°N

10°N

0°

10°S

30°N

20°N

10°N

0°

10°S

10°W 10°E 20°E 30°E0°

Fig. 13. Records of Polypterus ansorgii. , type locality; , verified records.

Ichthyol. Explor. Freshwaters, IEF-1094

River at Katagum, Esp. L. Lloyd. – BMNH 1953.4.28.126,

1, 503 mm SL; Nigeria: Hadeija-River, E. Trewavas. –

BMNH 1969.3.25.10, 1, 315 mm SL; Nigeria: Sokoto

River, M. H. Holden, Jun 1957. – BMNH 1902.11.10.28-

30, 2, 80-87 mm SL; Nigeria: Assay, W. Ansorge. –

BMNH 1902.11.10.27, 1, 161 mm SL; Nigeria: Abo, W.

Ansorge. – BMNH 1913.12.5.1, 1, 89 mm SL; Nigeria:

Anambra River, W. Crocombe. – MNHN 1925-0172, 1,

242 mm SL; Guinea: Kouroussa, Thomas. – MNHN

1961-0012, 4, 205-295 mm SL; Mali: Diafarabé, J. Daget,

22 May 1951. – MNHN 1961-0013, 2, 160-175 mm SL;

Mali: Diafarabé, J. Daget, 8 Apr 1950. – MNHN 1961-

0014, 1, 116.6 mm SL; Mali: Diafarabé, J. Daget, 27 Oct

1949. – MNHN 1961-1130, 1, 224 mm SL; Guinea: Niger

River at Faranah, Raimbault, 28 Aug 1958. – MNHN

1992-0769, 4, 210-233 mm SL; Guinea: Banie [= Niger]

River at Sanassiya, D. Paugy and R. Bigorne, 2 Mar

1989. – MRAC 72790-72793, 4, 179-253 mm SL; Mali:

Diafarabé, J. Daget, Nov 1946. – MRAC 73-012-P-0007-

0008, 2, 344-448 mm SL; Mali, Niger River at Mopti, H.

Matthes, 17 Sep 1969. – MRAC 92-014-P-0001, 1, 253 mm

SL; Nigeria: Orashi River at Odieke, C. B. Powell, 15

Nov 1991. – MRAC 92-014-P-0002, 1, 264 mm SL; Nige-

ria: Isemu Lake, C. B. Powell, 1-9 Nov 1991. lake ChaD

anD triButaries: BMNH 1928.7.4.1, 1, 361 mm SL; Chad:

Chari River below junction of Lodgone River, C.

Markham. – BMNH 1930.8.7.1-2, 2, 517-554 mm SL;

Chad: Chari River at Logone, J. Glover. – MNHN 1904-

0066, 1, 470 mm SL; Chad: Chari River, Chevalier and

Decorse. – MNHN 1928-0069, 1, 351 mm SL; Cameroon:

El Beid River at Afade, J. Monod. – MNHN 1959-0390,

1, 187 mm SL; Cameroon: El Beid; J. Blache and A.

Stauch, 5 Oct 1954. – MRAC 66466, 1, 405 mm SL;

Cameroon: Benoue River at Lere, J. Monod. – MRAC

153839-153840, 2, 416-486 mm SL; Chad: Mandoul

River at Bahr-Sara, A. Sutter, Mar 1965. – MRAC 73-

015-P-0034, 1, 336 mm SL; Cameroon: Logone River at

Guémé; W. Verheyen et al., 26 Nov 1970. – MRAC 73-

015-P-0035, 1, 608 mm SL; Cameroon: Logone River at

Guémé; W. Verheyen et al., 26 Nov 1970. – MRAC 73-

015-P-0036-0038, 2, 448-503 mm SL; Cameroon: Logone

River at Guémé, W. Verheyen et al., 26 Nov 1970. –

MRAC 73-015-P-0044-0046, 3, 211-377 mm SL; Came-

roon: Benoué River at Garoua, W. Verheyen et al., 7 Dec

1970. – MRAC 73-015-P-0047, 1, 269 mm SL; Cameroon:

Benoué River at Garoua, W. Verheyen et al., 8 Dec 1970.

nile Basin: BMNH 1850.7.29.1, 1, 517 mm SL; Egypt:

Nile, E. Rüppell. – BMNH 1899.4.28.1, 1, 550 mm SL;

Egypt: lower Nile River, Harrington and Harrington.

– BMNH 1899.4.28.2, 1, 466 mm SL; Egypt: lower Nile

River, Harrington and Harrington. – BMNH 1900.9.22.37,

1, 512 mm SL; Sudan: Bahr-el-Jebel, Capt. S. Fowler. –

BMNH 1906.3.3.1-3, 2, 261-299 mm SL; Egypt: west

Damietta, J. Mitchell. – BMNH 1907.12.2.117, 1, 261 mm

SL; Egypt: Nile River near Cairo; W. L. S. Loat, 15 Mar

1899. – BMNH 1907.12.2.118, 1, 667 mm SL; Sudan:

White Nile at Kawa, W. L. S. Loat. – BMNH 1907.12.2.119-

121, 3, 255-273 mm SL; Sudan: White Nile at Goz Abou

Gumah, W. L. S. Loat, 1 May 1901. – BMNH 1907.12.2.123-

124, 2, 203-214 mm SL; Sudan: White Nile at Ghab-el-

Aish, W. L. S. Loat. – BMNH 1907.12.2.125-134, 11,

252-554 mm SL; Sudan: White Nile at Fashoda, W. L.

S. Loat. – BMNH 1907.12.2.135, 1, 655 mm SL; Sudan:

White Nile near Kerro; W. L. S. Loat. – BMNH

1907.12.2.136, 1, 615 mm SL; Sudan: Lako No; W. L. S.

Loat. – MNHN 0000-2609, 2, 482-520 mm SL; Nile; Hit-

torf and Ehrenberg; 1844. – MNHN 0000-5762, 1, 583 mm

SL; Egypte: Nile; Clotbey; 1856. – MNHN 0000-5763, 1,

451 mm SL; Nile; Lenormand. – MRAC 140103, 1,

244 mm SL; Sudan: White Nile at Goz Abou Gumah,

W. L. S. Loat; 1907. – NMW 30297, 2, 426-429 mm SL;

Sudan: Bahr-el-Gazal; Marno, 1882. – NMW 30299, 1,

386 mm SL; Nile, Steindachner. – NMW 3302, 1, 443 mm

SL; Nile, Kotschy, 1842. – NMW 63209, 3, 245-267 mm

SL; Sudan: Khartoum, Drasche, 1876. – NMW 63210, 1,

465 mm SL; Nile, Steindachner, Nov 1910. – NMW 63211,

2, 321-357 mm SL; Nile; Steindachner, Oct 1910. – NMW

63212, 1, 364 mm SL; Sudan: Bahr-el-Seraf, Marno, 1881.

– NMW 63213, 1, 518 mm SL; Sudan: Bahr-el-Ghazal,

Steindachner, 1882. – NMW 63214, 1, 495 mm SL; Sudan:

“Zuflüsse des oberen Nil” [affluents of the Upper Nile],

Marno, 1881. – NMW 63215, 1, 497 mm SL; Sudan: White

Nile at Khor Attac, Werner, 1907. – NMW 63216, 1,

457 mm SL; Nile, Steindachner, Oct 1910. – NMW 63217,

1, 212 mm SL; Nile, Steindachner, 2 Nov 1910. – NMW

63219, 1, 434 mm SL; Sudan, Steindachner, Aug 1910.

– NMW 77728, 1, 528 mm SL; Sudan: Melut, 10°27' N

32°13' E; W. Sixl, 1981. – NMW 79061, 2, 485-572 mm

SL; Sudan: Melut, 10°27' N 32°13' E; W. Sixl, 1983. – NMW

9584, 1, 340 mm SL; side branch of Nile, Steindachner

and Marno, 1981. – ZSM 34546, 1, 330 mm SL; Sudan:

Omdourman [fishmarket], N. Pöllath, 14 Feb 2006.

katanga regiOn: MRAC 20671, 1, 389 mm SL; holotype

of P. bichir katangae, Democratic Republic of Congo:

Nyonga: Lake Upemba, G.-F. de Witte, 8-12 May 1925.

– MRAC 49319, 1, 109.5 mm SL; paratype of P. bichir

katangae, Democratic Republic of Congo: Lualaba Rivert

at Bukuma, P. Brien, Jun 1937. – MRAC 66561, 1,

134.5 mm SL; paratype of P. bichir katangae, Demo-

cratic Republic of Congo: Lualaba Rivert at Bukuma, P.

Brien, 23-26 Jun 1937. – MRAC 66562, 1, 149.2 mm SL;

paratype of P. bichir katangae, Democratic Republic of

Congo: Lualaba Rivert at Bukuma, P. Brien, 23-26 Jun

1937. – MRAC 66563, 1, 123.6 mm SL; paratype of

P. bichir katangae, Democratic Republic of Congo: Lu-

alaba Rivert at Bukuma, P. Brien, 23-26 Jun 1937

(Fig. 16). – IRSNB 68, 1, 415 mm SL; paratype of P. bichir

katangae, Democratic Republic of Congo: Lualaba River

at Maka, H. J. Bredo, 1 Feb 1939. – MRAC 178671, 1,

52.7 mm HL [only head preserved], paratype of P. bichir

katangae, Democratic Republic of Congo: Lake Kazi-

baziba, W. de Smet, 17 Nov 1956. – MRAC 178672, 1,

45.6 mm HL [only head preserved], paratype of P. bichir

katangae, Democratic Republic of Congo: Make, 50 km

from Bukuma, W. de Smet, 27 Dec 1955. – MRAC 178673,

1, 51.4 mm HL [only head preserved], paratype of

P. bichir katangae, Democratic Republic of Congo: Make,

50 km from Bukuma, W. de Smet, 27 Dec 1955. – MRAC

Moritz & Britz: Revision of Polypterus

69702, 1, 445 mm SL; Democratic Republic of Congo:

Lualaba River at Maka, M. Poll, 25 Jun 1947. – MRAC

79-01-P-0003, 1, 396 mm SL; Democratic Republic of

Congo: Lake Upemba: Mabwe, F. de Witte, 7-9 Sep

1947. WithOut lOCality Data: NMW 50276, 1, 585 mm

SL.

Additional material. nile Basin: DMM IE/10412, 2,

Sudan: Khartoum [central fish market]; T. Moritz et

al., Apr 2008.

Diagnosis. Polypterus bichir is distinguished from

all other members of the genus except P. ansorgii,

P. endlicherii and P. congicus, by 13 or more dorsal-

fin spines (vs. 12 or fewer) and the third dorsal

scale row being the first to reach ventral midline

(vs. second dorsal scale row reaching ventral

midline). Polypterus bichir is distinguished from

P. endlicherii and P. congicus by dorsal saddle-like

blotches, when present not confluent with, but

separate from lateral blotches (vs. dorsal and

lateral blotches confluent and always present).

When present, dorsal saddle blotches are more

numerous in P. bichir, with 9 or more such blotches

(vs. 6-8 in P. congicus and 4-6 in P. endlicherii), and

wide, i. e. at least 3 scale rows wide in P. bichir

(vs. less than 3 scale rows wide in P. congicus).

Polypterus bichir is distinguished from P. ansorgii

by more scales around the body (43-54 vs. 43-45)

and a larger maximum adult size (750 mm SL vs.

313). Most specimens can be distinguished from

P. ansorgii, P. congicus and P. endlicherii by 61 or

more scales in lateral series (55-70 [lower quartile

61] vs. 54-60 [upper quartile 60]).

Descriptive synopsis. Meristic and morphomet-

ric data in Tables 5-6. Body elongated with 55-70

scales and 57-67 vertebrae. Jaws terminal only in

juveniles; in large specimens lower jaw project-

ing beyond upper jaw. In large specimens head

and anterior body region often slightly dorso-

ventrally flattened (but never to the degree as in

large P. endlicherii and P. congicus). Size up to at

least 750 mm SL (820 mm TL).

Coloration. In life: coloration highly variable

(Fig. 17). Dorsal half of body brownish, light

brown, light grey or yellowish with dark brown

or grey markings varying from very faint to

conspicuous and pronounced: dorsal and lateral

blotches expressed only from about midlength,

more anteriorly replaced by two dark brown

longitudinal bands separated by lighter narrow

longitudinal stripe. Ventral half of body uniform

beige with no dark ventrolateral markings or with

few to many markings formed by aggregated dark

scales in anterior two-thirds of flanks, forming

irregular to regular lines; on posterior part of

ventrolateral body sometimes with several ventro-

lateral blotches in confluence with lateral blotches

forming irregular network of blotch lines. Dorsal

half of head light brown, grey or yellowish with

dark marbling of varying density. Ventral half of

head and cheek lighter with numerous dark spots

of variable sizes; often spotting extending down

onto gular plates. Lip markings formed by small

blotches. Iris yellow or orange with irregular dark

spots. Nasal tentacles showing same uniform or

marbled coloration as dorsal half of head. Also

markings on head very variable ranging from

virtually absent to much pronounced.

Pectoral fin yellow with dark brown elongate

spot-like markings arranged in several transversal

more or less regular bands; pectoral-fin base with

numerous large dark spots arranged to form a

blotch varying in expression from almost absent to

pronounced. Pelvic fin yellowish transparent with

or without dark spots arranged in more or less

regular bands. Soft part of dorsal fin and conflu-

ent caudal fin brown, yellowish or grey with dark

markings frequently expressed as densely set dark

spots loosely arranged in stripes. Dorsal-fin spines

grey, dark grey or brown with light or yellowish

spots arranged at approximately the same level as

in succeeding spines; similar pattern continuing

onto first and second order secondary fin rays

originating from spines; finlet-membrane grey-

transparent, usually without pattern, sometimes

with some dark marbling.

Different intensity of coloration not restricted

to any geographic areas, except the intensely

colored specimens from Koliba River. Plain

colored and more intensely pigmented specimens

present in same river basins at same time.

In preservative: all areas which are light

in life become pale in preservative; dark color

markings less pronounced; fine marbling on head

sometimes absent; dark spots on lower half of

head and body less intense. Dry paralectotype

(MNHN 0000-5806) without any color pattern;

ethanol preserved lectotype (MNHN 0000-5761)

only with faint color markings.

Distribution. Widely distributed in the major

river basins of the Nilo-Sahelo-Sudan region: Nile,

Chad, Niger, Volta and Senegal (Fig. 18). Addi-

tionally in few West African coastal basins: Gam-

Ichthyol. Explor. Freshwaters, IEF-1094

Fig. 14. Polypterus bichir, MNHN 0000-5761, 585 mm SL, male, lectotype; Egypt: Nile; E. Geoffroy Saint-Hilaire;

1799.

Fig. 15. Polypterus bichir, NMW 63244, 464 mm SL, male, syntype of P. lapradei; Taoué close to Richar-Toll [= Touey-

Marigot]; F. Steindachner; Nov 1868.

Moritz & Britz: Revision of Polypterus

bia, Casamanche and Geba River. Also distributed

in the Katanga area of the Congo basin, mainly

the Lualaba River. Occurrences of P. bichir in Lake

Turkana (e. g. Pellegrin, 1914; Holly, 1933; Poll,

1941a; Reitzer et al., 1972; Gosse, 1990; Seegers et

al., 2003) and Ouémé River basin (Gosse, 1990) are

questionable, as they are not supported either by

museum specimens or photographs.

Biology. Apparently most active at night, “active

swimmer and not essentially a bottom-liver or a

mudfish” (Harrington, 1899), living on muddy

substrates (Chad: Pellegrin, 1914). Polypterus bichir

prefers deeper depressions of muddy river beds

(Nile: Harrington, 1899) and feeds on small fish

of all types and on crustaceans (Chad: Pellegrin,

1914). Reproduction takes place during flood

season (Senegal: Reitzer et al., 1972) and mature

fishes enter flood plains for spawning (Gambia:

Budgett, 1900; Niger: Daget, 1954).

Etymology. The name refers to the local Egyptian

name, “bichir”, for the species (Geoffroy, 1802a-b).

Remarks. Some confusion has arisen about

which of three publications represents the origi-

nal description of this species (Geoffroy 1802a-b;

Lacépède, 1803). Geoffroy’s publication in the

Bulletin des Sciences (1802a) was published

between 21st of March and 20th of April in 1802.

This predates his publication in the Annales du

Muséum d’Histoire naturelle (Geoffroy, 1802b),

which was not published before 22nd of September

of the same year. Thus Geoffroy (1802a) made the

species name available, with the original spelling

as Polyptère bichir (which needs to be amended

to Polyptere bichir in accordance with Art. 33.3 of

the Code). One year later, Lacépède (1803: 340)

used the Latinised version, Polypterus bichir, in his

publication and this work that has been cited by

some authors, though incorrectly, as the descrip-

tion of the species (e. g. Holly, 1933; Schäfer, 2004;

Claeson & Hagadorn, 2008; Grandstaff et al., 2012;

Fricke et al., 2018). See also above under remarks

for the genus Polypterus.

Geoffroy Saint-Hilaire (1802a) did not specify

any type material and did not mention on how

Fig. 16. Polypterus bichir, MRAC 66563, 124 mm SL, juvenile, paratype of P. bichir katangae; Democratic Republic

of Congo: Lualaba Rivert at Bukuma; P. Brien; 23-26 Jun 1937.

Ichthyol. Explor. Freshwaters, IEF-1094

Table 5. Morphometric characters of Polypterus bichir. Range, mean and standard deviation (SD) include values

of lectotype. Negative values under ‘Pectoral to dorsal fin’ refer to dorsal-fin origin in front of pectoral-fin end.

lectotype range mean SD n

Standard length [mm] 585.0 109.5-750 364.0 140.9 139

Total length [mm] 660.0 131.9-820 407.7 155.5 131

In percent of standard length

Body depth 10.1 7.1-14.5 11.0 1.3 137

Body width 11.6 8.2-14.1 11.9 1.0 137

Head length 19.2 17.8-26.9 21.4 1.9 139

Pre-dorsal length 28.0 25.3-37.7 30.2 2.0 138

Dorsal-fin length 59.8 46.8-62.5 56.5 3.0 138

Pectoral to dorsal fin 4.0 -8.4-4.00 -3.6 1.7 135

Pre-pectoral length 19.6 16.7-26.6 21.6 1.8 137

Pectoral-fin extension 31.6 27.5-41.6 34.0 2.7 135

Inter-pectoral width 7.0 5.9-10.4 7.7 0.9 136

Pectoral-fin base width 3.1 1.8-3.9 2.9 0.4 137

Pre-pelvic length 70.3 64.8-73.6 70.0 1.5 138

Pre-anal length 85.1 80.6-88.3 85.0 1.4 138

Anal-fin ray length 11.4 7.3-16.3 12.3 1.6 136

Anal-fin base length 6.3 3.2-7.6 5.3 0.7 136

Caudal-peduncle length 4.1 2.2-4.8 3.4 0.5 136

In percent of head length

Head width 51.6 38.9-63.6 50.9 3.8 142

Interorbital width 17.8 15.6-24.8 19.0 1.7 141

Nostril distance 12.2 8.0-15.4 12.2 1.2 141

Snout length 19.0 14.6-22.3 19.5 1.4 141

Eye diameter 8.7 7.4-15.2 10.1 1.6 142

Postorbital length 72.5 62.3-74.2 69.6 2.1 142

Gular length 50.4 48.6-75.0 61.4 6.5 142

Length of first spine 22.7 11.0-28.5 22.4 3.0 133

Length of second spine 18.3 13.4-30.4 24.3 2.6 134

Width : length of first spine 15.2 12.7-36.7 17.8 3.8 133

Length of second : first spine 80.6 63.8-215.5 110.5 17.5 132

Table 6. Meristic characters of Polypterus bichir. Numbers in brackets indicate number of specimens with the

respective value. ‘All material’ includes values of lectotype.

lectotype all material

Dorsal-fin spines 16 13 (17), 14 (36), 15 (30), 16 (37), 17 (16), 18 (2)

Dorsal- and caudal-fin rays 19 18 (1), 19 (9), 20 (39), 21 (65), 22 (22), 23 (2), 24 (1)

Pectoral-fin rays 41 34 (1), 35 (4), 36 (1), 37 (13), 38 (15), 39 (21), 40 (25), 41 (25), 42 (18), 43 (8),

44 (3), 45 (1), 46 (1), 48 (1)

Pelvic-fin rays 13 10 (8), 11 (23), 12 (42), 13 (45), 14 (18), 15 (3)

Anal-fin rays 16 9 (1), 10 (3), 11 (11), 12 (28), 13 (44), 14 (33), 15 (16), 16 (1)

Scales in longitudinal series 67 55 (1), 56 (1), 58 (3), 59 (11), 60 (11), 61 (11), 62 (17), 63 (14), 64 (16), 65 (21),

66 (23), 67 (6), 68 (2), 70 (1)

Scales around body 44 43 (6), 44 (7), 45 (15), 46 (22), 47 (26), 48 (18), 49 (11), 50 (16), 51 (8), 52 (5),

53 (2), 54 (2)

Pre-dorsal scales 13 10 (2), 11 (6), 12 (23), 13 (39), 14 (35), 15 (25), 16 (3), 17 (4)

Pre-pelvic scales 48 38 (1), 39 (1), 40 (5), 41 (2), 42 (5), 43 (10), 44 (15), 45 (20), 46 (23), 47 (19),

48 (16), 49 (15), 50 (5), 51 (1)

Total number of vertebrae –57 (4), 58 (2), 59 (1), 61 (3), 62 (3), 63 (3), 64 (4), 65 (2), 66 (6), 67 (2)

Moritz & Britz: Revision of Polypterus

Fig. 17. Polypterus bichir. a-b, 351 mm SL, aquarium import, “Koliba-coloration”, Guinea; c, Senegal: Nikologo-

Koba National Park (photo by M. Reichard); d, 340 mm SL; Sudan: Khartoum [central fish market] (photo by N.

Pöllath).

many specimens he based his description. His

remark that P. bichir has 16, 17 or 18 finlets indi-

cates that he had at least three specimens. In the

MNHN there are only two specimens preserved

from Geoffroy’s collection dated to 1799: MNHN

0000-5761 (Fig. 14) and MNHN 0000-5806. Both

were originally stored in ethanol, but the latter

specimen was made into a dry specimen in 1810,

according to Bertin (1940) who listed these two

specimens as holotype and paratype, respectively.

This view was followed by Gosse (1984). Subse-

quently, Eschmeyer (1998) designated MNHN

Ichthyol. Explor. Freshwaters, IEF-1094

0000-5761 as lectotype thus rendering MNHN

0000-5806 a paralectotype.

In 1869, Steindachner published the descrip-

tion of a new bichir from the Senegal, Polypterus

lapradei. He noted that the essential difference

between P. lapradei and P. bichir is the shape of

the head, whereas counts of dorsal-fin spines

and scales show an overlapping gradient: 14-15

vs. 15-17 dorsal-fin spines, 60-62 vs. 64 scales

in lateral row, 13-14 vs. 12-13 pre-dorsal scales

(values given in Steindachner, 1869).

Steindachner (1870) mentioned four speci-

mens, which he used for his description. All

four specimens are deposited at the Naturhis-

torisches Museum in Vienna and catalogued as

three objects with numbers NMW 63242, NMW

3243 (2 specimens) and NMW 63244 (Fig. 15).

Regarding P. lapradei, Eschmeyer (1998: 870) noted

“Syntypes: (3) NMW 63053 (1).”, thus indicating

the presence of four syntypes, although he only

provided the catalog number for one of them.

This specimen, NMW 63053, however, was not

mentioned in the original description, as it ex-

ceeds the maximal length given by Steindachner

(1870) and therefore cannot be regarded as part

of the type series. One syntype (NMW 63244) was

photographed by F. Schäfer (2004) and referred to

as “holotype” with the catalogue number NMW

32244 in the text, a lapsus for NMW 63244, as

evidenced by the photographed label.

Polypterus lapradei had been regarded as a

valid species until Poll (1941a-b, 1942) referred to

it as a subspecies of P. bichir. Since the beginning

of the 1970s this view has become widely ac-

cepted (Gosse, 1984). In his keys for West African

polypterid species, Gosse (1990, 2003) employed

the following criteria to distinguish both subspe-

cies: number of scales in a longitudinal series and

number of dorsal-fin spines, but noted that both

meristic characters show overlap. He also stated

and illustrated disjunct distribution areas for the

two subspecies: the Benoué River and river basins

west of it for P. bichir lapradei, and the Chad basin

and river basins east of it for P. bichir bichir (Gosse,

1990, 2003). Schäfer (2004) in his popular book on

bichirs treated P. lapradei again as a valid species,

and distinguished it from P. bichir by details of

the color pattern: P. lapradei was considered to

possess usually clearly marked longitudinal

stripes in the anterior region of body (vs. absence

30°N

20°N

10°N

0°

10°S

30°N

20°N

10°N

0°

10°S

10°W 10°E 20°E 30°E0°

Fig. 18. Records of Polypterus bichir. , type locality; , verified records; , other records; , questionable

records.

Moritz & Britz: Revision of Polypterus

-3.0 -2.5 -2.0 -1.5 -1.0 -0.5 0.5 1.0 1.5

PC1

PC2

-2.4

-1.6

-0.8

0.8

1.6

2.4

3.2

4.0

-3.0 -2.5 -2.0 -1.5 -1.0 -0.5 0.5 1.0 1.5

-2.4

-1.6

-0.8

0.8

1.6

2.4

3.2

4.0

PC1

PC2

Fig. 19. Scatterplots of first and second components (PC 1 and PC 2) of Polypterus bichir specimens throughout its

distributional range. a, meristic characters: scales in longitudinal series, pre-dorsal scales, pre-pelvic scales,

dorsal-fin spines, pectoral-fin rays, pelvic-fin rays, anal-fin rays, soft rays in confluent dorsal and caudal fin;

b, meristic characters as in Figure 19a, plus morphometric characters: body depth, body width, head length, head

width, pre-dorsal length, length of spinous part of dorsal fin, distance from distal tip of adducted pectoral fin to

first finlet, pre-pectoral length, extension of pectoral fin, inter-pectoral width, width of pectoral-fin base, pre-

pelvic length, pre-anal length, length of longest ray in anal fin, length of anal-fin base, caudal-peduncle length,

inter-orbital width, nostril distance, eye diameter, post-orbital length. All data are normalized. , , West Africa

[, Western coastal basins; , Senegal basin; , Volta basin; , Niger basin, without Benoue]; , , Chad and Benoué

[, Benoué basin; , Chad basin]; , , Nile basin; , , Katanga region.

of such stripes) and a uniformly plain colored

area above the anal fin (vs. a pattern consisting

of light blotches on a darker background). In our

view the color pattern of P. bichir is more variable

throughout the distribution area (see above).

Furthermore, the aquarium-specimens regarded

by Schäfer (2004) as P. lapradei originated from

Nigeria, and the one regarded as P. bichir came

Ichthyol. Explor. Freshwaters, IEF-1094

from the upper Niger in Guinea. These putative

origins of his P. bichir and P. lapradei individuals

do not fit the distribution patterns published by

Gosse (1990, 2003).

A second subspecies, Polypterus bichir katangae

(Fig. 16), was described by Poll (1941a) from the

Katanga region in the Congo basin based on a

holotype and five paratypes. He distinguished

this sub-species from P. bichir bichir by fewer

dorsal-fin spines (12-14 vs. 14-18), fewer scales in

a lateral series (58-60 vs. 63-70) and fewer scales

around the body (44-46 vs. 46-54; values given

by Poll, 1941a). For his comparison Poll (1941a)

used only the values provided by Boulenger (1907)

for P. bichir and studied just a single additional

non-Katanga specimen of P. bichir, an individual

from Cameroon.

Our analysis of the meristic and morphometric

data collected for this study revealed no clear

distinction between the supposed subspecies of

P. bichir (Fig. 19) and show great overlap between

the West African specimens and those with a Nile,

Chad or Katanga origin. Exclusion of all West

African specimens from the analysis results in a

distinction between Nile plus Chad specimens

on the one hand and the Katanga specimens on

the other hand (Fig. 19a). The PCA analysis dem-

onstrates that distant populations within a large

distribution area can become distinguishable from

each other. But, if sampling covers the whole area

the values merge and form a continuous range.

Plotting several meristic data grouped according

to their geographical origin on box-and-whisker-

plots (Fig. 20) shows some trends for P. bichir: the

Katanga

W.Africa

Chad

Nile

12 13 14 15 16 17 18 19

Katanga

W.Africa

Chad

Nile

54 56 58 60 62 6 4 66 68 70 72

ScL

Katanga

W.Africa

Chad

Nile

9 10 11 12 13 14 15 16 17 18

ScpD

Katanga

W.Africa

Chad

Nile

36 38 40 42 44 46 48 50 52

ScpP

Fig. 20. Box-and-whisker plots of selected meristic data of P. bichir from throughout its distributional range,

grouped into geographical regions. Nile (n = 54); Lake Chad, including Chari and Benoué (n = 17); West Africa,

from Niger on to the West (n = 58); Katanga region (n = 8). DS, dorsal-fin spines; ScL, scales in longitudinal series;

ScpD, pre-dorsal scales; ScpP, pre-pelvic scales.

Moritz & Britz: Revision of Polypterus

more west they occur individuals from the Nile

across the Chad basin to West Africa tend to have

fewer scales in the lateral line, fewer dorsal-fin

spines and fewer pre-pelvic scales; specimens

from the Katanga region also show low values

in these parameters similar to the West African

individuals (Fig. 20). Despite the geographical

trend in the number of dorsal-fin spines there is

no such trend in the number of pre-dorsal scales

(Fig. 20).

At first glance the color pattern appears to fol-

low a similar geographical trend: specimens are

more pigmented and contrasted the more west

they were collected. This trend is culminating in

the coloration of the population from the Corubal

River [= Koliba River] along the border of Guinea-

Bissau and Guinea from which conspicuously pig-

mented specimens (Fig. 17 a,b) enter the aquarium

trade under the trade name P. lapradei “Koliba”

or P. sp. “Koliba”. Specimens from Katanga also

show a more pronounced, contrasted coloration

(Fig. 16). Specimens collected in the Lower Niger,

Chad area and Nile basin (Fig. 17d) on the other

hand are often much more faintly pigmented, and

faint specimens are also common in rivers of West

Africa. Yet, conspicuously colored specimens

are not just restricted to the Corubal River and

Katanga region, but have also been collected in

the Niger River close to its delta (e. g. MRAC 92-

014-P-0001, MRAC 92-014-P-0002) and from the

Nile north of Cairo (e. g. BMNH 1907.12.2.117).

Based on analysis of our data we synonymise

P. lapradei and P. bichir katangae with P. bichir and

only recognize a single species, however, with

geographical variation in meristic counts. The

cause of the sometimes striking differences in

coloration remains unclear.

Recently, Otero et al. (2006) described a well-

preserved almost complete fossil of Polypterus as a

new species, P. faraou. Meristic and morphometric

characters of the fossil P. faraou (values taken

from Otero et al., 2006), however, fall completely

within the ranges we report here for P. bichir.

Thus, there is little reason to consider the fossil

P. faraou distinct from P. bichir. Polypterus faraou

may potentially be conspecific with P. bichir, a

conclusion that needs to be further tested.

Polypterus congicus Boulenger, 1898

(Figs. 21-23, Tables 7-8)

Polypterus congicus Boulenger, 1898: 418.

Material examined. 66 specimens. type speCimens:

BMNH 1897.9.30.28, lectotype (Fig. 21, present des-

ignation), male, 656 mm SL; Democratic Republic of

Congo: Stainley Falls. – BMNH 1899.2.20.33, 1, para-

lectotype, 167 mm SL; juvenile; Democratic Republic

of Congo: New Antwerp [Makanza]. – MRAC 79, 1,

paralectotype, male, 580 mm SL; Democratic Republic

of Congo: Mayanga, Wilventh, 1896. – MRAC 119, 1,

paralectotype, 205 mm SL; juvenile, Democratic Re-

public of Congo: Leopoldville [= Kinshasa], Wilventh,

1896. COngO river: BMNH 1899.6.27.1, 1, 579 mm SL;

Democratic Republic of Congo: Upper Congo. – BMNH

1899.6.28.1, 1, 202 mm SL; Democratic Republic of

Congo: Brazaville, M. Meuse. – BMNH 1900.6.23.14,

192 mm SL; Democratic Republic of Congo: Bolobo, G.

Grenfell. – BMNH 1919.9.10.1, 1, 270 mm SL; Democratic

Republic of Congo: Stanley Falls. – BMNH 1919.9.10.1,

1, 265 mm SL; Democratic Republic of Congo: Luvua

River at Ankoro, K. Banister, 1974/1975. – IRSNB 9960,

1, 315 mm SL; Democratic Republic of Congo: Congo

River at Yangambi, A. Hulot, Dec 1949. – IRSNB 100015,

1, 471 mm SL; Democratic Republic of Congo: Congo

River at Yangambi, A. Hulot, 1948. – MNHN 1886-0292,

1, 485 mm SL; Democratic Republic of Congo: Congo

River at Nangtchou; S. de Brazza. – MRAC 2243, 1,

271 mm SL; Democratic Republic of Congo: Stanleyville,

C. Christy, before 1913. – MRAC 19804, 1, 145.9 mm SL;

Democratic Republic of Congo: Stanleyville, Richard,

1929. – MRAC 43966, 1, 225 mm SL; Democratic Republic

of Congo: Kinshasa, A. Tinant, 1933. – MRAC 103366,

1, 260 mm SL; Democratic Republic of Congo: Stanley

Pool, A. Werner, Jun 1955. – MRAC 103993-103996, 4,

239-274 mm SL; Democratic Republic of Congo: Stanley

Pool, A. Werner, Jun 1955. – MRAC 115689, 1, 205 mm

SL; Democratic Republic of Congo: Stanley Pool, Brien

and Poll, 6 Apr 1956. – MRAC 115692, 1, 724 mm SL;

Democratic Republic of Congo: Stanley Pool, Brien and

Poll, Sep 1957. – MRAC 73-022-P-0012, 1, 237 mm SL;

Democratic Republic of Congo: Stanley Pool: marai

Limgundu, J. Mandeville, 9 Apr 1958. – MRAC 73-022-

P-0013-0015, 3, 194-245 mm SL; Democratic Republic of

Congo: Stanley Pool, J. Mandeville, 9 Apr 1958. – MRAC

A7-033-P-0029, 1, 361 mm SL; Democratic Republic

of Congo: Malebo Pool: Mipongo island, 4°16'19" S

15°30'41" E; Hanssens et al., 11 Sep 2007. – MRAC

A7-033-P-0030, 1, 257 mm SL; Democratic Republic

of Congo: Malebo Pool: Mipongo island, 4°16'19" S

15°30'41" E; Hanssens et al., 11 Sep 2007. – RMNH 20873,

1, 207 mm SL; Democratic Republic of Congo: Stanley

Pool, A. Werner, Jul 1955. – ZSM 38691, 1, 505 mm SL:

Democratic Republic of Congo: Malbeo Pool: Kenkole

[fishmarket], U. Schliewen et al., 29 Jul 2008. kasai

river anD triButaries: MRAC 66950, 1, 374 mm SL;

Democratic Republic of Congo: Kasai River: region de

Ichthyol. Explor. Freshwaters, IEF-1094

Mushie, Vleeschouwers, Oct 1945. – MRAC 67073, 2,

453-503 mm SL; Democratic Republic of Congo: Kasai

River: region de Mushie, Vleeschouwers, Oct 1945. Ou-

Bangui river: MRAC 58071, 1, 216 mm SL; Democratic

Republic of Congo: Oubangui River at Yakoma, Rosy,

1938. – MRAC P-182255, 1, 354 mm SL; Democratic

Republic of Congo: Dungu River at Gangala na Bodio,

C. d’Elzius, 1954/1955. – MRAC P-179888-179889,

2, 386-412 mm SL; Democratic Republic of Congo:

Dungu River at Gangala na Bodio, M. Poll, Nov 1956.

Table 8. Meristic characters of Polypterus congicus. Numbers in brackets indicate number of specimens with the

respective value. ‘All material’ includes values of lectotype.

lectotype all material

Dorsal-fin spines 14 11 (1), 12 (2), 13 (13), 14 (39), 15 (11), 16 (1)

Dorsal- and caudal-fin rays 19 17 (1), 18 (4), 19 (37), 20 (21), 21 (3)

Pectoral-fin rays 43 37 (2), 38 (2), 39 (6), 40 (6), 41 (10), 42 (12), 43 (14), 44 (8), 45 (7), 46 (1)

Pelvic-fin rays 13 10 (1), 11 (3), 12 (15), 13 (23), 14 (21), 15 (3), 16 (1)

Anal-fin rays 16 10 (2), 11 (2), 12 (13), 13 (17), 14 (16), 15 (12), 16 (5)

Scales in longitudinal series 56 54 (2), 55 (10), 56 (24), 57 (17), 58 (9), 59 (4), 60 (1)

Scales around body 49 41 (1), 42 (1), 44 (4), 45 (3), 46 (14), 47 (14), 48 (11), 49 (8), 50 (10), 51 (1)

Pre-dorsal scales 14 11 (5), 12 (22), 13 (28), 14 (10), 15 (2)

Pre-pelvic scales 42 39 (1), 40 (3), 41 (15), 42 (18), 43 (18), 44 (8), 45 (4)

Total number of vertebrae 55 52 (1), 53 (1), 55 (3), 57 (1)

Table 7. Morphometric characters of Polypterus congicus. Range, mean and standard deviation (SD) include values

of lectotype. Negative values under ‘Pectoral to dorsal fin’ refer to dorsal-fin origin in front of pectoral-fin end.

lectotype range mean SD n

Standard length [mm] 656.0 145.9-788 405.5 168.6 66

Total length [mm] 740.0 174.8-876 478.0 189.6 58

In percent of standard length

Body depth 12.3 9.2-16.6 11.8 1.6 66

Body width 14.9 10.8-17.1 14.1 1.3 66

Head length 20.9 20.0-26.1 22.6 1.5 66

Pre-dorsal length 32.3 27.2-36.3 31.5 1.8 66

Dorsal-fin length 56.9 49.3-64.7 55.9 3.0 66

Pectoral to dorsal fin -3.2 -8.4--1.0 -4.6 1.7 66

Pre-pectoral length 20.6 19.5-26.8 23.2 1.6 66

Pectoral-fin extension 34.8 31.6-43.2 36.6 2.8 66

Inter-pectoral width 9.0 6.8-12.1 9.5 0.9 65

Pectoral-fin base width 3.7 2.8-4.3 3.5 0.3 66

Pre-pelvic length 70.7 64.5-73.1 70.2 1.4 66

Pre-anal length 85.8 82.6-90.6 85.4 1.2 66

Anal-fin ray length 11.3 10.3-17.4 13.4 1.5 66

Anal-fin base length 6.1 3.1-7.4 5.7 0.8 66

Caudal-peduncle length 3.7 2.3-4.9 3.5 0.5 66

In percent of head length

Head width 62.4 50.5-67.2 57.7 3.3 67

Interorbital width 24.9 18.3-27.4 21.5 1.7 67

Nostril distance 15.9 10.0-16.6 13.8 1.4 67

Snout length 22.0 19.4-24.5 21.9 1.0 67

Eye diameter 7.9 6.7-13.1 9.3 1.3 67

Postorbital length 70.5 63.3-72.0 68.6 1.9 67

Gular length 72.7 52.3-72.3 61.6 6.0 67

Length of first spine 17.5 17.1-27.2 22.0 2.3 65

Length of second spine 18.6 19.7-29.1 23.6 2.2 65

Width : length of first spine 26.0 13.1-27.3 18.2 3.4 65

Length of second : first spine 106.7 91.5-128.5 108.0 7.6 65

Moritz & Britz: Revision of Polypterus

lake tanganyika anD triButaries: BMNH 1906.9.6.1-

4, 4, 465-577 mm SL; Democratic Republic of Congo:

Lake Tanganyika at Kalambo, J. E. S. Moore. – BMNH

1906.9.8.1, 1, 540 mm SL; Zambia: Lake Tanganyika

at Kituta, W. Cunnington. – BMNH 1936.6.15.18, 1,

601 mm SL; Lake Tanganyika, C. Christy. – BMNH

1936.6.15.19-21, 3, 381-603 mm SL; Lake Tanganyika,

C. Christy. – BMNH 1936.6.15.23-26, 6, 579-693 mm SL;

Lake Tanganyika, C. Christy. – BMNH 2005.4.22.1-2,

2, 576 mm SL [of one specimen only head preserved],

Zambia: Lake Tanganyika: mouth of Lufubu River,

8°33'40" S 30°43'24" E; H. Buescher, 10 Nov 2004. – IRSNB

9443, 1, 600 mm SL; Tanzania: delta of Malagarasi River,

20 May 1947. – MRAC 88875, 1, 788 mm SL; Democratic

Republic of Congo: Albertville [= Kalemie] [fishmarket],

M. Poll, 1 Feb 1944. – MRAC 190227, 1, 375 mm SL;

Zambia: Lake Tanganyika: Chinyika bay: Kasaba, H.

Matthes, 20-23 Apr 1967. – MRAC 93-152-P-0323, 1,

251 mm SL; Tanzania: delta of Malagarasi River, L.

de Vos, 21 Aug 1993. katanga: BMNH 1975.6.20.1,

1, 265 mm SL; Democratic Republic of Congo: Luvua

River at Akoro, K. Banister, 1974/1975. – MRAC 3205,

1, 523 mm SL; Democratic Republic of Congo: Sankuru

River at Kondue, Luja, before 1913. – MRAC 3206, 1,

470 mm SL; Democratic Republic of Congo: Sankuru

River at Kondue, Luja, before 1913. – MRAC 3207, 1,

329 mm SL; Democratic Republic of Congo: Sankuru

River at Kondue, Luja, before 1913. – MRAC 3210, 1,

584 mm SL; Democratic Republic of Congo: Sankuru

River at Kondue, Luja, before 1913. – MRAC 34775,

1, 360 mm SL; Democratic Republic of Congo: Luvua

River at Kiambi, G. F. de Witte, 18 Apr-3 May 1931.

– MRAC 35030, 1, 351 mm SL; Democratic Republic of

Congo: Luvua River at Kiambi, G. F. de Witte, 4-20

May 1931. – MRAC 49320, 1, 625 mm SL; Democratic

Republic of Congo: Lualaba River at Maka, P. Brien, Jul

1937. – MRAC 66560, 1, Democratic Republic of Congo:

Lualaba River at Maka, P. Brien, Jul 1934. – MRAC

69701, 1, 688 mm SL; Democratic Republic of Congo:

Lualaba River at Maka, M. Toll, 9 Apr 1958. – MRAC

90-047-P-0088, 1, 274 mm SL; Democratic Republic of

Congo: Lualaba River at km 47 on road Kisangani-Wanie

Rukula, L. de Vos, 28 May 1990.

Fig. 21. Polypterus congicus, BMNH 1897.9.30.28, 656 mm SL, male, lectotype (present designation); Democratic

Republic of Congo: Stainley Falls.

Ichthyol. Explor. Freshwaters, IEF-1094

Additional material. COngO river: MRAC 72-022-P-

0010, 1, Democratic Republic of Congo: Stanley Pool, J.

Mandeville, 10 Jan 1955. OuBangui river: MRAC 1306,

1, juvenile, Democratic Republic of Congo: Oubangui

River at Banzyville [= Mobayi-Mbongo], Royanne, 1901.

– MRAC 58057-58070, 14, Democratic Republic of Con-

go: Oubangui River at Yakoma, Rosy, 1939. katanga:

IRSNB 4870, 1, Democratic Republic of Congo: Lualaba

River at Maka, J. H. Bredo, 1 Feb 1939. – MRAC 30547,

[only remnants], Democratic Republic of Congo: Luvua

River at Kiambi, 1930. – MRAC 178712, 1, Democratic

Republic of Congo: Kikondja, W. de Smet, 14 Apr 1956.

Diagnosis. Polypterus congicus is distinguished

from all other members of the genus except P. an-

sorgii, P. bichir and P. endlicherii, by third dorsal

scale row being the first to reach ventral midline

(vs. second). Polypterus congicus is distinguished

from P. ansorgii, and P. bichir by 6-8 (rarely 9)

dorsolateral bars formed by the confluence of

dorsal and lateral blotches (vs. dorsal and lateral

blotches separated, not forming continuous bars)

and from P. endlicherii by more numerous (6-8,

rarely 9 vs. 4-6) and narrower bars (less than 3

scale rows wide vs. wider than 3 scale rows).

Descriptive synopsis. Meristic and morpho-

metric data in Tables 7-8. A large species of

the P. bichir-group reaching at least 788 mm SL

(876 mm TL). Body moderately elongated. Jaws

terminal in juveniles only; in large specimens

lower jaw projecting beyond upper jaw. Anterior

body region and head becoming dorso-ventrally

flattened with increasing size.

Coloration. In life: dorsal half of body grey to

brown with slender dark grey to black dorsolateral

bars; on anterior body bars directed obliquely

posteriorly, on posterior body obliquely anteriorly

(Fig. 22). Ventral half of body light, white or yel-

lowish, sometimes with few irregular dark grey

spots arranged approximately in a horizontal line

as ventrolateral markings (much less conspicuous

than in P. endlicherii). Dorsal half of head including

upper jaw brown or yellowish-brown with dense

irregular dark brown to black spots and marbling;

cheeks lighter. Ventral half of head with fewer but

larger dark spots; lower jaw light with dark spots

usually forming several vertical lines. Iris yellow

to orange with dense brown marbling. Pectoral,

Fig 22. Polypterus congicus. a-b, aquarium import (photos: Schuzo Nakano/Aqualog).

Moritz & Britz: Revision of Polypterus

pelvic and anal fins yellowish with fine, densely

set, dark brown spots and marbling (usually not

expressed as lines as in P. endlicherii). Base of pec-

toral fin with dark spots and blotches concentrated

in distal part. Soft dorsal fin and confluent caudal

fin hyaline to grey with light yellowish spots, rays

darker. Dorsal-fin spines grey or brownish with

dark brown irregular pattern; finlet membrane

translucent with color pattern similar to that of

soft dorsal fin.

A conspicuously colored specimen from Lake

Tanganyika was depicted by Schäfer (2004: 61-63).

The specimen had strongly contrasted color mark-

ings on body and regularly, radially arranged

dark markings on roof of head and opercular

region. Schäfer (2004) suggested that this might

represent a new species, by labelling it Polypterus

sp. aff. congicus. We see, however, no reason to

regard it as anything other than a strongly and

particularly colored P. congicus.

In preservative: color pattern similar to life

coloration, but yellow and yellowish markings in

life now white, and black markings in life dark

grey (Fig. 21).

Distribution. Polypterus congicus is widely dis-

tributed in the Congo River basin, and tributaries

and southern part of Lake Tanganyika (Fig. 23).

Biology. Within the Congo basin the species

seems to be restricted to the main river and

neighbouring water bodies and it has been re-

ported to enter the flooded forest during high

water levels (Gosse, 1965). In the southern part

of Lake Tanganyika the species inhabits areas

with clear water and sandy substrate with large

boulders (Büscher, 2004). Interestingly, so far only

large specimens have been recorded from Lake

Tanganyika; it remains unclear in which areas

breeding and juvenile growth take place (Büscher,

2004). Polypterus congicus feeds on bottom dwell-

ing organisms (Gosse, 1965).

Etymology. Not explicitly stated, but apparently

an allusion to the type locality (Congo).

Remarks. Boulenger’s (1898) original description

was based on four syntypes. One specimen which

can be clearly assigned to the original type series

(based on collection date, collection place, number

30°N

20°N

10°N

0°

10°S

30°N

20°N

10°N

0°

10°S

10°W 10°E 20°E 30°E0°

Fig. 23. Records of Polypterus congicus. , type locality; , verified records.

Ichthyol. Explor. Freshwaters, IEF-1094

of dorsal-fin spines and number of lateral line

scales) is: BMNH 1897.9.30.28 (Fig. 21). Fricke et

al. (2018) incorrectly listed this specimen as ‘holo-

type’. We designate herein BMNH 1897.9.30.28

as lectotype of P. congicus. Three additional

specimens from New Antwerp, Leopoldville and

Manayanga were mentioned by Boulenger (1898)

and these paralectotypes are most likely: BMNH

1899.2.20.33, MRAC 79 and MRAC 119.

Polypterus delhezi Boulenger, 1899

(Figs. 24-26, Tables 9-10)

Polypterus delhezi Boulenger, 1899: 61, Pl. XXX,

Fig. 2.

Material examined. 44 specimens. type speCimens:

MRAC 422, lectotype (Fig. 24, present designation),

male, 314 mm SL; Democratic Republic of Congo: Lake

Leopold at Kutu, P. Delhez. – BMNH 1899.2.20.17, 1,

paralectotype, female, 270 mm SL; Democratic Republic

of Congo: New Antwerp [= Makanza], Wilvert and Wa-

genaar. COngO river: BMNH 1975.8.15.67, 1, 241 mm SL;

Democratic Republic of Congo: Congo River, A. Fraser-

Brunner. – MNHN 1886-0294, 1, 311 mm SL; Democratic

Republic of Congo: Nangtchou, S. de Brazza. – MRAC

103987, 1, 260 mm SL; Democratic Republic of Congo:

Stanley Pool, A. Werner, Jun 1955. – MRAC 154587, 1,

165.4 mm SL; Democratic Republic of Congo: Stanley

Pool, P. Brichard, 1966. – MRAC 177711, 1, 277 mm

SL; Democratic Republic of Congo: Stanley Pool, J. van

Orshoven, 5 May 1964. – MRAC 177717, 1, 251 mm SL;

Democratic Republic of Congo: Bolobo; N’Kele, 1958.

– MRAC 73-022-P-0008-0009, 2, 250-285 mm SL; Demo-

cratic Republic of Congo: Stanley Pool, J. Mandeville,

5 Sep 1958. – MRAC 88-025-P-0642, 1, 135.0 mm SL;

Democratic Republic of Congo: Congo River at Bumba,

L. de Vos, 30 Jan 1988. – MRAC 91-013-P-0640-0642, 3,

214-295 mm SL; Democratic Republic of Congo: N' Sele

River [affluent of Congo River] close to Kinshasa, 4°08' S

16°40' E; M. Tshibwabwa Sinaseli, 1985/1987. – MRAC

A7-0033-P-0031-0033, 3, 226-234 mm SL; Democratic

Republic of Congo: Canal Kisanga at Inga, 5°27'55" S

13°34'58" E; Hanssens et al., 29 Aug 2007. – RMNH 20874,

1, 190 mm SL; Democratic Republic of Congo: Stanley

Pool, A. Werner, Jul 1955. kasai river: MRAC 67060,

1, 280 mm SL; Democratic Republic of Congo: Fimi

River at Bungi, Vleeschouwers, 22 Oct 1945. – MRAC

68750-68754, 4, 173-250 mm SL; Democratic Republic

of Congo: Fimi River at Mushie, Vleeschouwers, 21 Sep

1946. – MRAC 138889, 1, 278 mm; Democratic Republic

of Congo: Mushie, M. Creeter, 1957. – MRAC 66832, 1,

258 mm SL; Democratic Republic of Congo: Kasai River

at Fimi, Vleeschouwers, Sep 1941. – MRAC 66852, 1,

260 mm SL; Democratic Republic of Congo: Kasai River

at Fimi, Vleeschouwers, Sep 1941. lake tumBa: IRSNB

4871, 1, 350 mm SL; Democratic Republic of Congo: Lake

Tumba at N’Kosso Norma, G. de Loneux, 31 Dez 1938.

– MRAC 14688, 1, 102.4 mm SL; Democratic Republic

of Congo: Lake Tumba at Bikoro, D. Schouteden, 1921.

– MRAC 14689, 1, 99.5 mm SL; Democratic Republic

of Congo: Lake Tumba at Bikoro, D. Schouteden, 1921.

– MRAC 57751-57752, 2, 340-348 mm SL; Democratic

Republic of Congo: Lake Tumba, G. de Loneux, 1928.

– MRAC 14690; Democratic Republic of Congo: Lake

Tumba, G. de Loneux, 1928. likOuala river: MNHN

1962-0349, 9, 60.8-111.6 mm SL; Democratic Republic

Fig. 24. Polypterus delhezi, MRAC 422, 314 mm SL, male, lectotype (present designation); Democratic Republic of

Congo: Lake Leopold at Kutu; P. Delhez.

Moritz & Britz: Revision of Polypterus

of Congo: Likouala River at Mossaka, Stauch, 24 Feb

1961. OuBangui river: MRAC 179773, 1, 247 mm SL;

Democratic Republic of Congo: Ngiri River [affluent

of Oubangui River], P. van Leynseele, 1970. ruki river

anD triButaries: MRAC 80642, 1, 329 mm SL; Demo-

cratic Republic of Congo: Tshuapa River at Bokuma, P.

Lootens, 20 Sep 1952. – MRAC 73-022-P-003, 1, 158.4 mm

SL; Democratic Republic of Congo: Tshuapa River at

Boende, R. Philippe, Jun 1956. aquarium speCimen:

NMW 90940, 1, 217 mm SL; Tiergarten Schönbrunn.

Additional material. COngO river: MRAC 39459-

39461, 3, Democratic Republic of Congo: Leopoldville

[= Kinshasa], A. Tinant, 1933. – MRAC 43978, 1, Demo-

cratic Republic of Congo: Leopoldville [= Kinshasa], A.

Tinant, 1935. – MRAC 47995, 1, Democratic Republic

of Congo: Leopoldville [= Kinshasa], A. Tinant, 1937.

– MRAC 67462, 1, Democratic Republic of Congo:

Leopoldville [= Kinshasa], Bureau. – MRAC 68034, 1,

Democratic Republic of Congo: Leopoldville [= Kin-

shasa], De Vier, Aug 1945. – MRAC 102572-102576,

5, Democratic Republic of Congo: Kingabwa, J. Man-

deville, Aug-Sep 1955. – MRAC 115693, 1, Democratic

Republic of Congo: Stanley Pool, Brien and Poll, 4 May

1956. – MRAC 115694, 1, Democratic Republic of Congo:

Stanley Pool, Brien and Poll, 23 Jul 1956. – MRAC 115695,

1, Democratic Republic of Congo: Stanley Pool, Brien

and Poll, 26 Sep 1957. – MRAC 115696, 1, Democratic

Republic of Congo: Stanley Pool, Brien and Poll, 4 Oct

1957. – MRAC 115697-115701, 5, Democratic Republic of

Congo: Stanley Pool, Brien and Poll, Sep 1957. – MRAC

118720, 1, Democratic Republic of Congo: Stanley Pool,

P. Brichard, 1956. – MRAC 140106-140108, 3, Democratic

Republic of Congo: environs of Leopoldville [= Kinsha-

sa], van de Weyer, 1960. – MRAC 177721, 1, Democratic

Republic of Congo: Bolobo, N’Kele, 1956. – MRAC 73-

Fig. 25. Polypterus delhezi, aquarium specimens. a, 240 mm SL, adult; b, 72 mm SL, juvenile; c, early juvenile

(photo c: Schuzo Nakano/Aqualog).

Ichthyol. Explor. Freshwaters, IEF-1094

33-P-1, 1, Democratic Republic of Congo: environs of

Leopoldville [= Kinshasa], R. Henrion, 1971. – MRAC

73-022-P-0001-0002, 2, Democratic Republic of Congo:

Stanley Pool: Mikunga passage, J. Mandeville, 29 Oct

1957. – MRAC 73-022-P-0003, 1, Democratic Republic of

Congo: Stanley Pool: Nsele River, J. Mandeville, 29 Oct

1957. – MRAC 73-022-P-0004, 1, Democratic Republic of

Congo: Stanley Pool: Ndjiili River, J. Mandeville, 30 Oct

1957. – MRAC 73-022-P-0006, 1, Democratic Republic

of Congo: Stanley Pool, J. Mandeville, 8 Nov 1957.

Table 10. Meristic characters of Polypterus delhezi. Numbers in brackets indicate number of specimens with the

respective value. ‘All material’ includes values of lectotype.

lectotype all material

Dorsal-fin spines 10 10 (3), 11 (33), 12 (8)

Dorsal- and caudal-fin rays 16 15 (7), 16 (34), 17 (3)

Pectoral-fin rays 39 31 (1), 32 (1), 33 (3), 34 (11), 35 (9), 36 (3), 37 (6), 38 (7), 39 (3)

Pelvic-fin rays 10 9 (9), 10 (24), 11 (10), 12 (1)

Anal-fin rays 12 9 (4), 10 (8), 11 (9), 12 (11), 13 (9), 14 (2), 15 (1)

Scales in longitudinal series 55 54 (4), 55 (19), 56 (17), 57 (4)

Scales around body 37 35 (1), 36 (6), 37 (9), 38 (9), 39 (11), 40 (6), 41 (2)

Pre-dorsal scales 17 13 (7), 14 (24), 15 (8), 16 (3), 17 (2)

Pre-pelvic scales 37 35 (1), 36 (8), 37 (16), 38 (15), 39 (3)

Total number of vertebrae –54 (1), 55 (2)

Table 9. Morphometric characters of Polypterus delhezi. Range, mean and standard deviation (SD) include values

of lectotype. Negative values under ‘Pectoral to dorsal fin’ refer to dorsal-fin origin in front of pectoral-fin end.

lectotype range mean SD n

Standard length [mm] 314.0 60.8-350 212.9 87.2 44

Total length [mm] 339.0 77.9-382 235.6 89.8 40

In percent of standard length

Body depth 10.4 8.5-14.2 11.6 1.1 44

Body width 10.8 9.9-13.2 11.7 0.8 44

Head length 17.0 16.2-23.4 19.0 2.0 44

Pre-dorsal length 34.0 28.0-38.2 32.5 2.1 44

Dorsal-fin length 56.0 47.1-61.7 56.0 3.1 44

Pectoral to dorsal fin 2.4 -3.8-3.3 -0.3 1.5 44

Pre-pectoral length 17.2 15.4-23.2 19.4 1.8 44

Pectoral-fin extension 30.3 28.4-38.0 32.9 2.7 44

Inter-pectoral width 5.8 5.8-9.7 7.6 0.9 44

Pectoral-fin base width 2.9 2.6-3.7 3.1 0.3 44

Pre-pelvic length 65.6 62.5-67.6 65.0 1.1 44

Pre-anal length 84.7 81.8-87.8 84.4 1.2 44

Anal-fin ray length 9.0 7.9-15.2 11.9 1.8 44

Anal-fin base length 6.2 3.9-7.0 5.2 0.7 44

Caudal-peduncle length 3.6 2.2-5.0 3.5 0.6 44

In percent of head length

Head width 53.2 45.3-63.7 56.7 3.6 44

Interorbital width 21.8 18.1-24.5 21.5 1.3 44

Nostril distance 13.5 9.6-17.1 13.2 1.5 44

Snout length 19.2 18.0-24.3 21.4 1.4 44

Eye diameter 12.3 10.8-18.0 13.3 1.8 44

Postorbital length 66.9 57.5-68.9 64.8 2.6 44

Gular length 58.0 56.0-69.5 60.1 2.7 44

Length of first spine 34.2 17.9-35.9 26.0 3.8 44

Length of second spine 35.2 21.0-40.4 29.0 3.4 43

Width : length of first spine 16.8 15.4-35.1 22.4 3.9 43

Length of second : first spine 103.0 89.2-142.1 112.8 11.8 42

Moritz & Britz: Revision of Polypterus

kasai river: MRAC 2804, 1, Democratic Republic of

Congo: Bokala, D. J. Maes. – MRAC 2805, 1, Democratic

Republic of Congo: Bokala, D. J. Maes. lake tumBa:

MRAC 14686, 1, Democratic Republic of Congo: Lake

Tumba at Tondu, D. Schouteden, 1921. – MRAC 14687,

1, Democratic Republic of Congo: Lake Tumba at Tondu,

D. Schouteden, 1921. – MRAC 14690, 1, Democratic Re-

public of Congo: Lake Tumba at Bikoro, D. Schouteden,

1921. – MRAC 14691, 1, Democratic Republic of Congo:

Lake Tumba at Bikoro, D. Schouteden, 1921. ruki river

anD triButaries: IRSNB 21048, 1, Democratic Republic

of Congo: Ruki River, Kiss, Feb 1980. – MRAC 74871,

1, Democratic Republic of Congo: Bokungu, L. Dupuis,

1950. – MRAC 177776, 1, Democratic Republic of Congo:

Boende, P. Brichard, 1969.

Diagnosis. Polypterus delhezi is distinguished

from species of the P. bichir group by its second

dorsal scale row reaching ventral midline (vs.

third scale row) and lateral line scales with cen-

tral pores and entire posterior margin (vs. with

incision at posterior margin). Polypterus delhezi

is distinguished from all remaining Polypterus

species except P. senegalus by low number of pre-

dorsal scales (13-17 vs. 20-37). It is distinguished

from P. senegalus by the presence of a series of

vertical dark brown to black dorsolateral bars

(vs. absence) and by more dorsally located eyes

(lower margin of orbit visible in dorsal view vs.

not visible). Furthermore, Polypterus delhezi differs

from P. senegalus in usually having more dorsal-

fin spines (10-12, median 11 vs. 8-11, median 9)

and smaller interorbital width (18.1-24.5 % HL

vs. 22.4-30.7).

Descriptive synopsis. Meristic and morpho-

metric data in Tables 9-10. Body moderately

elongated. Mouth terminal, upper jaw usually not

projecting beyond lower jaw; in rare cases upper

jaw very slightly projecting. Eyes in dorso-lateral

position. First dorsal-fin spine at about vertical

through posterior margin of pectoral fin. Size up

to at least 350 mm SL (382 mm TL).

Coloration. In life: dorsal half of body light

grey with 5-9 black, vertical or oblique dorsolat-

eral bars of approximately two scale rows width

formed by the confluence of dorsal with preceding

(rarely succeeding) lateral blotches; bars some-

times with light or yellowish margin; confluence

frequently incomplete resulting in separate dorsal

and lateral blotches (Fig. 25). Ventral half of body

30°N

20°N

10°N

0°

10°S

30°N

20°N

10°N

0°

10°S

10°W 10°E 20°E 30°E0°

Fig. 26. Records of Polypterus delhezi. , type locality; , verified records.

Ichthyol. Explor. Freshwaters, IEF-1094

whitish or cream, sometimes with ventrolateral

markings expressed as longitudinal stripe and/or

blotches surrounding lighter yellowish blotches,

especially in juveniles (Fig. 25c). Dorsal half of

head, iris and upper lip grey with irregular dark

grey to black marbling; ventral half of head and

cheeks white, with suborbital stripe expressed as

line of dark spots and extending posteriorly to

dark spots and blotches on lower half of opercular

region. Frequently with dark line formed by series

of spots ventral and parallel to suborbital stripe;

lower lip and jaw whitish with distinct black spots.

Pectoral fin with dark spots arranged in two or

three narrow rows; distal part of pectoral-fin base

with dark markings, not forming a distinct blotch.

Pelvic fin with dark spots sometimes arranged

in thin rows. Otherwise pectoral and pelvic fins

whitish, yellowish or translucent. Dorsal, caudal

and anal fins dark grey with light, yellowish,

irregular pattern; distal parts of fins sometimes

darker. Dorsal-fin spines grey with dark grey to

black markings at mid-level and in distal parts;

finlet-membrane transparent with dark markings,

often a dark irregular area at mid-level.

In preservative: dorsal half of body light

brown to beige; bars conspicuous, black or dark

brown; color pattern on head, including subor-

bital stripe less distinct than in life; ventrolateral

markings less distinct (Fig. 24).

Distribution. Restricted to the major rivers in the

central and lower Congo basin (Fig. 26).

Biology. Life history largely unknown.

Etymology. Named after Paul Delhez who col-

lected the lectotype.

Remarks. Boulenger (1899) mentioned two speci-

mens in the original description of Polypterus

delhezi, without designating a holotype. Fricke et

al. (2018) stated that Boulenger (1909) provided a

lectotype designation in his catalogue of African

fishes. There, however, Boulenger (1909: 14) only

mentioned one “type” deposited in MRAC and

another “type” being part of the BMNH collection,

clearly regarding both specimens as syntypes.

We designate herein MRAC 422, the specimen

illustrated by Boulenger (1899, pl. XXX, fig. 2;

1909, fig. 9), as the lectotype of P. delhezi (Fig. 24).

Polypterus endlicherii Heckel, 1848

(Figs. 27-31, Tables 11-12)

Polypterus endlicherii Heckel, 1848: 310, Pl. 22,

fig. 1.

Material examined. 64 specimens. type spe Cimen :

NMW 91244, holotype (Fig. 27), 684 mm SL; dry speci-

men; Sudan: Nile River at Khartoum, [likely] Kotschy.

COastal river Basins Of Côte D’ivOire anD ghana:

BMNH 1923.3.2.2-3, 2, 136-211 mm SL; Côte d’Ivoire:

Bandama River, W. Lowe. – BMNH 1934.8.31.1, 1,

167 mm SL; Ghana: Ashanti Forest: Ejura, W. Lowe.

– BMNH 1969.4.28.10, 1, 296 mm SL; Ghana: Afram

River at Aframoso, W. R. Smith, 5 Sep 1952. – MNHN

1894-0392, 1, 206 mm SL; Côte d’Ivoire: Bandama

River at Tiassale, Pobeuin. – MNHN 1894-0393, 1,

192 mm SL; Côte d’Ivoire: Bandama River at Tiassale,

Pobeuin. – MNHN 1960-0177, 193 mm SL; Burkina

Faso: Yanon River [tributary of Comoé], Arnoult and

d’Aubenton. – MNHN 1991-0439, 1, 344 mm SL; Côte

d’Ivoire: Bandama River at Lamto, Lamotte, Jul 1970.

– MRAC 74-014-P-0003, 1, 449 mm SL; Côte d’Ivoire:

Lake Kossou, S. Kyeli, 17 Dec 1973. – MRAC 79-036-

P-0001, 1, 261 mm SL; Côte d’Ivoire: Lagune Ebrié at

Layo, D. F. E. Thys van den Audenaerde, 20 Oct 1979.

– MRAC 80-019-P-0001, 1, 388 mm SL; Côte d’Ivoire:

Sassandra River at Soubré, G. Teugels and L Risch,

24-25 Apr 1980. – MRAC 85-029-P-0001, 1, 281 mm

SL; Côte d’Ivoire: Boubo River at Babokon, G. Teugels,

8-9 May 1985. – MRAC 85-029-P-0002, 1, 285 mm SL;

Côte d’Ivoire: Boubo River at Babokon, G. Teugels,

9-10 May 1985. – MRAC 85-055-P-001, 1, 188 mm SL;

Burkina Faso/Côte d’Ivoire [border]: Léreba River at

Léreba, G. Teugels, 24 Nov 1985. – MRAC 86 013-P-0001,

201 mm SL; Côte d’Ivoire: Bandama River at Tiassale,

G. Teugels, 3-4 Apr 1986. – MRAC 87-018-P-0001,

1, 188 mm SL; Burkina Faso/Côte d’Ivoire [border]:

Léreba River at Léreba, G. Teugels, 29 Jan 1987. lake

ChaD anD triButaries: MNHN 1919-0074, 1, 175 mm

SL; Central African Republic: Gribingui River, Baudon.

– MNHN 1928-0071, 1, 234 mm SL; Chad: Mayo Kebbi:

Lere, Monod. – MNHN 1938-0032, 1, 213 mm SL; Chad:

Logone River at Lai, Thomas. – MRAC 73-026-P-0006, 1,

209 mm SL; Chad: south of Hollom: Tofoul, 11°10'20" N

15°03'10" E; M. Y. Brandily, 24 Aug 1969. Ouémé river

Basin: MRAC 73-001-P-0006, 1, 262 mm SL; Benin:

Porto Novo, P. de Kimpe, 15 Nov 1963. vOlta river

Basin: BMNH 1949.10.20.1, 1, 272 mm SL; Ghana: Volo,

Buxton. – MNHN 2007-0246, 1, 344 mm SL; Togo: Oti

River at Mango, C. Lévêque, 3 Nov 1982. – MRAC

140923-140924, 2, 183.1-206 mm SL; Burkina Faso: Kou

River [tributary of Mouhoun], B. Roman, 4 Jun 1964.

niger river anD triButaries: BMNH 1902.11.10.31, 1,

139.2 mm SL; Nigeria: Abo, S. W. J. Ansorge, 20 Oct 1901.

– BMNH 1913.12.5.2-3, 2, 96.4-129.7 mm SL; Nigeria

Anambra River, W. Crocombe. – BMNH 1936.11.24.1,

1, 241 mm SL; Nigeria: Kaduna River, J. Welman. –

Moritz & Britz: Revision of Polypterus

BMNH 1959.8.18.79, 1, 153.1 mm SL; Nigeria: Lokoja,

Maclaren, 1 Nov 1948. – MNHN 1961-0015, 1, 276 mm

SL; Mali: Niager River at Diafarabe, J. Daget, 8 Apr 1950.

– MNHN 1961-0016, 1, 205 mm SL; Mali: Niager River at

Diafarabe, J. Daget, 8 Apr 1950. – MNHN 1962-0444, 1,

197 mm SL; Cameroon: Benoue River at Mayo-Rey, A.

Stauch, May 1960. – MNHN 1986-0051, 3, 226-294 mm

SL; Guinea: Milo River at Boussoule, C. Lévêque, Feb

2006. – MRAC 140111, 1, 219 mm SL; Cameroon: Benoue

River, A. Stauch. nile river Basin: BMNH 1865.11.15.4,

Table 12. Meristic characters of Polypterus endlicherii. Numbers in brackets indicate number of specimens with

the respective value. ‘All material’ includes values of holotype.

holotype all material

Dorsal-fin spines 12 11 (5), 12 (34), 13 (22), 14 (3)

Dorsal- and caudal-fin rays (damaged) 18 (12), 19 (33), 20 (15), 21 (1), 22 (1)

Pectoral-fin rays 40 35 (1), 38 (4), 39 (9), 40 (7), 41 (7), 42 (16), 43 (5), 44 (8), 45 (5), 46 (2)

Pelvic-fin rays 14 11 (3), 12 (13), 13 (17), 14 (17), 15 (8), 16 (3), 17 (3)

Anal-fin rays 13 9 (1), 10 (1), 11 (2), 12 (16), 13 (24), 14 (16), 15 (3)

Scales in longitudinal series 55 53 (3), 54 (9), 55 (18), 56 (24), 57 (6), 58 (1), 59 (1), 60 (1)

Scales around body 43 39 (4), 40 (2), 41 (8), 42 (13), 43 (11), 44 (12), 45 (9), 46 (3), 47 (1), 48 (1)

Pre-dorsal scales 13 12 (18), 13 (28), 14 (10), 15 (7), 16 (1)

Pre-pelvic scales 40 39 (1), 40 (11), 41 (16), 42 (13), 43 (14), 44 (6), 45 (3)

Total number of vertebrae –53 (1), 54 (4), 55 (1), 56 (2)

Table 11. Morphometric characters of Polypterus endlicherii. Range, mean and standard deviation (SD) include values

of holotype. Negative values under ‘Pectoral to dorsal fin’ refer to dorsal-fin origin in front of pectoral-fin end.

holotype range mean SD n

Standard length [mm] 684.0 96.4-780 324.5 169.4 64

Total length [mm] (damaged) 115.9-764 356.1 170.6 59

In percent of standard length

Body depth 10.6 8.6-16.0 11.2 1.6 64

Body width 15.1 11.9-16.2 14.1 1.1 64

Head length 20.8 18.4-26.4 22.4 1.8 64

Pre-dorsal length 30.0 27.4-47.5 32.1 3.0 64

Dorsal-fin length 59.8 49.5-62.8 56.2 3.4 64

Pectoral to dorsal fin -2.0 -7.7-0.0 -3.9 1.8 63

Pre-pectoral length 20.1 19.4-27.4 22.8 1.9 64

Pectoral-fin extension 32.2 31.4-43.2 36.3 2.8 64

Inter-pectoral width 9.1 8.0-12.2 9.6 0.9 64

Pectoral-fin base width 3.6 3.0-4.5 3.8 0.3 64

Pre-pelvic length 67.3 66-73 70.1 1.6 64

Pre-anal length 88.2 82.6-89.9 85.6 1.5 64

Anal-fin ray length 12.0 9.9-14.9 12.4 1.3 63

Anal-fin base length 6.4 3.2-7.3 5.3 0.7 64

Caudal-peduncle length 2.8 1.5-5.4 3.7 0.7 64

In percent of head length

Head width 57.9 51.1-71.7 59.5 4.1 64

Interorbital width 21.7 17.9-26.7 21.8 2.1 64

Nostril distance 11.4 10.9-16.8 13.4 1.2 64

Snout length 15.9 14.9-22.9 19.8 1.6 64

Eye diameter 7.6 7.0-13.2 9.7 1.5 64

Postorbital length 68.7 64.1-74.4 69.1 2.2 64

Gular length 53.0 50.9-73.8 60.3 5.4 64

Length of first spine 22.2 11.0-28.6 22.0 3.5 63

Length of second spine 22.6 18.5-29.7 25.0 2.4 62

Width : length of first spine 21.5 12.8-44.8 21.5 5.6 63

Length of second : first spine 101.6 85.7-269.8 117.0 25.6 61

Ichthyol. Explor. Freshwaters, IEF-1094

1, 335 mm SL; Egypt: Nile River below cataracts, Peth-

erick. – BMNH 1907.12.2.137, 1, 230 mm SL; Sudan:

near Goz Shebesha, W. L. S. Loat, 3 Jan 1901. – BMNH

1907.12.2.138, 1, 611 mm SL; Sudan: White Nile near

Kawa, W. L. S. Loat, 5 Jan 1901. – BMNH 1907.12.2.139,

1, 565 mm SL; Sudan: White Nile at Goz Abu Gumah,

W. L. S. Loat. – BMNH 1907.12.2.140, 1, 574 mm SL;

Sudan: White Nile at Fashoda, W. L. S. Loat, 28 Mar

1901. – BMNH 1907.12.2.141, 1, 525 mm SL; Sudan: Lake

No, W. L. S. Loat, 15 Feb 1901. – BMNH 1907.12.2.142, 1,

444 mm SL; Sudan: White Nile at Gondokoro, W. L. S.

Loat, 11 Mar 1902. – BMNH 1907.12.2.143-144, 2, 248-

652 mm SL; Sudan: Omdurman: Sheduah, W. L. S. Loat,

31 Dec 1900. – MNHN 2001-2180, 1, 224 mm SL; Sudan:

aab

Fig. 27. Polypterus endlicherii, NMW 91244, 684 mm SL, female, holotype; Sudan: Nile River at Khartoum; [likely]

Kotschy.

Fig. 28. Polypterus endlicherii, view of predorsal region. a, NMW 91244, holotype; b, illustration of holotype

(Fenzl et al., 1849); arrow points to scale anomaly.

Moritz & Britz: Revision of Polypterus

White Nile: Jebel Aulia reservoire at Kowa, T. Roberts.

– NMW 10954, 1, 304 mm SL; Nil, Steindachner, Nov

1910 (Fig. 29). – NMW 50278, 1, 340 mm SL; Sudan: Bahr

el Seraf, Steindachner, 1881. – NMW 63023, 1, 704 mm

SL; Sudan: Bahr el Arab, Marno, 1881. – NMW 63024, 1,

705 mm SL; Sudan: White Nile, Kotschy, 1852. – NMW

63054, 1, 698 mm SL; Sudan: Bahr el Ghazal, [likely]

Marno, 1881. – NMW 63218, 1, 279 mm SL; Sudan:

Khartoum, Drasche and Steindachner [?], 1876. – NMW

63237, 2, 270-343 mm SL; Sudan, Steindachner, 1910. –

NMW 63239, 1, 367 mm SL; Sudan, Steindachner, 1910.

– NMW 63240, 2, 381-388 mm SL; Sudan, Steindachner,

Aug 1910. – NMW 63241, 1, 550 mm SL; Sudan: White

Nile at Ed Dueim, Werner, 1907. – NMW 91233, 1,

780 mm SL; [likely] Sudan: Khartoum, [likely] Reitz,

[likely] 1851. – ZSM 35162, 1, 254 mm SL; Sudan: White

Nile at Kosti, 13°10'17" N 32°40'07" E; D. Neumann, 13

Jan 2007. – ZSM 39631, 1, 558 mm SL; Sudan: Omdour-

man [fishmarket], T. Moritz et al., Apr 2008. aquarium

traDe: ZSM 34041, 1, 216 mm SL; Guinea: [likely] Niger

River at Faranah and Kobikoro, F. Schäfer, 2004.

Additional material. COastal river Basins Of Côte

D’ivOire anD ghana: MRAC 140109, 1, Côte d’Ivoire:

Bandama River, Lowe. niger river Basin: MRAC 91-100-

P-0004, 1, Nigeria: Nun River at Kaiama, 5°08' N 6°18' E;

C. B. Powell, 12-13 Sep 1991. vOlta river Basin: DMM

IE/10393, 1, Benin: Pendjari National Park: Pendjari

River at Pont Arly, 11°28'05" N 1°34'01" E; T. Moritz,

25 Nov 2002. – DMM IE/10399, 1, Benin: Pendjari Na-

tional Park: Mare Hippotrague, 11°23'14" N 1°22'15" E;

T. Moritz, 14 Apr 2007. – DMM IE/10400, 3, Benin:

Pendjari National Park: Pendjari River at Hotel Pendjari,

11°24'33" N 1°35'22" E; T. Moritz, Apr 2007 . – MRAC

93-127-P-0001, 1, Ghana: Daka River [tributary of Lake

Volta] at Dindu, 8°10' N 0°20' W; P. C. Goudswaard, 16

Apr 1993. – MRAC 93-127-P-0002, 1, Ghana: White Volta

at Kope, 8°45' N 1°28' W; P. C. Goudswaard, 24 Sep 1992.

Diagnosis. Polypterus endlicherii is distinguished

from all other members of the genus except P. an-

sorgii, P. bichir and P. congicus, by third dorsal

scale row being the first to reach ventral midline

(vs. second). Furthermore, Polypterus endlicherii

is distinguished from all Polypterus species ex-

cept P. bichir and P. congicus by short pre-dorsal

length of only 21.7-27.4 % SL (vs. 27.4-47.5).

Polypterus endlicherii is distinguished from P. an-

sorgii, P. bichir and P. congicus by its unique color

pattern: few (4-5, rarely 6), broad (more than 3

scale rows wide), dark transverse bars extending

from dorsum to middle of flank by confluence of

dorsal and lateral blotches sometimes including

ventrolateral markings (vs. dorsal and lateral

blotches distinct, not confluent and forming bars

in P. bichir and P. ansorgii, or 6-8 narrow bars in

P. congicus).

Descriptive synopsis. Meristic and morphomet-

ric data in Tables 11-12. Large species, up to at

least 780 mm SL. Body moderately elongated.

Jaws terminal in juveniles but in larger specimens

lower jaw projecting beyond upper jaw. Anterior

Fig. 29. Polypterus endlicherii, NMW 10954, 304 mm SL, female; Nile River.

Ichthyol. Explor. Freshwaters, IEF-1094

body region and head becoming more dorso-

ventrally flattened with increasing size (Fig. 9).

Coloration. In life: dorsal half of body grey to

brownish-grey with broad dark-grey saddle-

like dorsolateral bars; bars more than three scale

rows wide, frequently also confluent with ven-

trolateral markings; bars less regular in caudal

area (Fig. 30). Ventral half of body light, whitish,

with ventrolateral markings usually expressed as

irregular dark-grey to black blotches sometimes

confluent with wide bars; occasionally with an

additional longitudinal line further ventrally.

Dorsal half of head including upper jaw dark

grey with dark brown to black spots. Lower half

of head including lower jaw light, whitish, with

dark spots on lateral side of head and lower jaw,

but not on gular plate; spots sometimes arranged

in more or less regular lines. Iris and skin around

eye with same coloration as head. Pectoral and

Fig. 30. Polypterus endlicherii. a, large specimen ~400 mm SL; Côte d’Ivoire: Comoé National Park: Comoé River;

b-c, ~100 mm SL, juvenile; Benin: Pendjari National Park: Pendjari River.

Moritz & Britz: Revision of Polypterus

pelvic fins light, whitish, with dark spots and

small blotches; pelvic fin usually with no or faint

darker markings; pattern on pectoral fin arranged

in 3-5 more or less regular lines. Base of pectoral

fin with irregular spots and small blotches, more

concentrated in distal portion; pectoral-fin base

blotch also present; well developed blotch also on

medial side of pectoral fin base. Dorsal, caudal

and anal fins grey with dark irregular mark-

ings. Dorsal-fin spines lighter than dorsal part

of body, with few dark spots; finlet membranes

translucent with irregular grey color markings,

more pronounced in distal part; coloration and

markings of finlet membranes similar to those of

soft dorsal fin, caudal fin and anal fin.

In preservative: color pattern similar to that

in live specimens, but generally less contrasted

(Fig. 29).

Two specimens from the Niger River at Diafa-

rabé, Mali, (MNHN 1961-0015, MNHN 1961-0016)

with unusual color pattern resembling that of

P. congicus, however, consisting of narrow rather

than broad bars and with ventrolateral markings

expressed as irregular blotches on ventral half of

flanks.

Distribution. Widely distributed in Nile, Chad

and Niger basins; and in coastal rivers of Côte

d’Ivoire, i. e. Sassandra River, Boubo River, Ban-

dama River, Ebrié Lagoon and Comoé River, and

Volta Basin; a single record from coastal lagoon

of Ouémé River (Fig. 31).

Etymology. Named after Stephan Ladislaus

Endlicher (1804-1849), an Austrian botanist and

colleague of Heckel.

Remarks. The exact date of the original descrip-

tion of P. endlicherii remains somehow obscure,

as the publication of Heckel is labelled as “1846-

1849”. Kottelat (2013: 492) convincingly argued

that the most likely actual year of publication

of this article is 1848, which we follow here. The

corresponding figure for the original description

was not published in Heckel (1848), but in Fenzl

et al. (1849: plate 22).

There is some confusion about the holotype

of P. endlicherii. Heckel (1848) did not refer to any

collection number, but the description clearly

refers to a single specimen. About 50 years later,

Steindachner, then curator at the Vienna museum,

30°N

20°N

10°N

0°

10°S

30°N

20°N

10°N

0°

10°S

10°W 10°E 20°E 30°E0°

Fig. 31. Records of Polypterus endlicherii. , type locality; , verified records; , other records.

Ichthyol. Explor. Freshwaters, IEF-1094

added “Polypterus endlicheri Heck. Typ.” to the la-

bel of NMW 63024, a spirit specimen of about the

same size of that in the original description. This

specimen was subsequently referred to by several

authors (Eschmeyer, 1998; Schäfer, 2004; Fricke

et al., 2018) as the holotype. In the original de-

scription, however, Heckel (1848) provided some

additional comments on the holotype, stating

among other things that it is a dry specimen with

12 dorsal-fin spines. Both these features clearly

exclude NMW 63024 from being the holotype.

There are two dry specimens of P. endlicherii in the

Vienna collection, NMW 91233 and NMW 92144,

both with 12 dorsal-fin spines. Only NMW 92144

(Fig. 27), however, has the matching size and its

color pattern corresponds quite well to that of the

drawing accompanying the original description.

In addition, the shape of the spiracular bones

on the skull roof of NMW 92144 matches that of

the same bones in the drawing of the holotype

(Fig. 28), with the exception of the second bone on

the right side, which is divided in three parts in

NMW 92144, but illustrated as a single bone. The

number and arrangement of the small spiracular

bones and the color pattern are quite variable in

the species and thus provide a useful source to

identify the holotype. Finally, a scale anomaly in

the 10th and 11th pre-dorsal scale row of NMW

92144 matches a similar anomaly in the draw-

ing of the holotype: the third scale of the tenth

row on the left side and the second scale of the

eleventh row seem to be fused (Fig. 28b; Fenzl et

al., 1849). This, in our opinon, demonstrates that

NMW 91244 is the holotype of P. endlicherii. It is

the specimen collected by Kotschy in Sudan, likely

in Khartoum, and sold to the NMW as Polypterus

bichir in 1840 (acquisition book 1840.XI.17). The

second dry specimen of P. endlicherii in Vienna,

NMW 91233, is very likely a specimen collected

on 30 Nov 1851 in Khartoum by C. Reitz (Reitz,

1852) and has no type status.

Polypterus mokelembembe

Schliewen & Schäfer, 2006

(Figs. 32-34, Tables 13-14)

Polypterus mokelembembe Schliewen & Schäfer,

2006: 24, fig. 1a.

Material examined. 32 specimens. type speCimens:

MRAC 87921, holotype (Fig. 32), female, 166 mm

SL; Democratic Republic of Congo: Maringa River

at Wamba, 0°11' N 22°28' E; H. Bertels, 8 Nov 1952. –

Fig. 32. Polypterus mokelembembe, MRAC 87921, 166 mm SL, female, holotype; Democratic Republic of Congo:

Maringa River; H. Bertels; 8 Nov 1952.

Moritz & Britz: Revision of Polypterus

MRAC 101372, 1, paratype, female, 221 mm SL; Demo-

cratic Republic of Congo: Bokuma, Hulstaert, 28 Aug

1955. – MRAC 79224-79225, 2, paratypes, 71-78 mm

SL; Democratic Republic of Congo: Bokuma, Lootens,

1-15 Jul 1952. – MRAC 72434-72435, 2, paratypes, 81-

172 mm SL; Democratic Republic of Congo: surround-

ing of Leopoldville. – BMNH 1907.12.3.4, 1, paratype

of P. mokelembembe and paralectotype of P. retropinnis,

male, 192 mm SL; Democratic Republic of Congo: Alima

River at Diele, S. de Brazza. – MNHN 1886-0297, 1, male,

paratype of P. mokelembembe and paralectotype of P. re-

tropinnis, 207 mm SL; Democratic Republic of Congo:

Alima River at Leketi, S. de Brazza. lefini river: MRAC

A4-046-P-0716, 1, 207.1 mm SL; Democratic Republic of

Congo: Itsotso River 5 km upstream of confluence with

Lefini River. – MRAC unreg., 1, 179 mm SL; Democratic

Republic of Congo: Lefini River, 17 Sep 2007. – MRAC

unreg., 6, 175.4-195 mm SL; Democratic Republic of

Congo: Lefini River, 8 Sep 2007. – MRAC unreg., 1,

218 mm SL; Democratic Republic of Congo: Lefini River,

15 Sep 2007. – MRAC unreg., 9, 127.3-244 mm SL; Demo-

cratic Republic of Congo: small tributary of Lefini River,

2 Sep 2008. – MRAC unreg., 1, 181 mm SL; Democratic

Republic of Congo: Lefini River, 17 Sep 2007. – MRAC

unreg., 1, 214 mm SL; Democratic Republic of Congo:

Lefini River, 19 Sep 2007. – MRAC unreg., 1, 261 mm

SL; Democratic Republic of Congo: Lefini River, 30 Apr

2007. aquarium traDe: ZSM 33571, 3, 194-232 mm SL;

Democratic Republic of Congo: exported via Kinshasa.

Fig. 33. Polypterus mokelembembe, aquarium import from Congo. a, 232 mm SL, female; b, head of specimen in a;

c, 149 mm SL, male.

Ichthyol. Explor. Freshwaters, IEF-1094

Table 14. Meristic characters of Polypterus mokelembembe. Numbers in brackets indicate number of specimens

with the respective value. ‘All material’ includes values of holotype.

holotype all material

Dorsal-fin spines 76 (7), 7 (17), 8 (3)

Dorsal- and caudal-fin rays 15 13 (1), 15 (16), 16 (10)

Pectoral-fin rays 27 24 (1), 25 (3), 26 (3), 27 (8), 28 (6), 29 (2), 30 (4)

Pelvic-fin rays 98 (3), 9 (14), 10 (9), 11 (1)

Anal-fin rays 9 (4), 10 (11), 11 (2), 12 (5), 13 (4)

Scales in longitudinal series 58 57 (2), 58 (8), 59 (12), 60 (4), 61 (1)

Scales around body 36 31 (1), 32 (4), 33 (3), 34 (5), 35 (9), 36 (5)

Pre-dorsal scales 33 30 (2), 31 (2), 33 (5), 34 (2), 35 (10), 36 (2), 37 (4)

Pre-pelvic scales 43 43 (1), 44 (3), 45 (4), 46 (11), 47 (6), 48 (2)

Total number of vertebrae –58 (2), 59 (3), 60 (1), 61 (1)

Table 13. Morphometric characters of Polypterus mokelembembe. Range, mean and standard deviation (SD) include

values of holotype.

holotype range mean SD n

Standard length [mm] 166.1 125.5-261 194.5 30.2 27

Total length [mm] –142.7-280 214.0 31.8 26

In percent of standard length

Body depth 10.0 9.5-12.8 11.2 0.9 27

Body width – 9.9-12.4 11.0 0.6 26

Head length 16.9 14.8-16.9 15.8 0.6 27

Pre-dorsal length 59.2 52.8-66.3 59.8 3.2 27

Dorsal-fin length 32.5 26.8-40.0 32.3 3.2 27

Pectoral to dorsal fin 29.7 23.3-38.4 31.2 3.4 27

Pre-pectoral length 16.0 15.5-17.6 16.6 0.5 27

Pectoral-fin extension –26.8-30.6 28.5 1.0 26

Inter-pectoral width –6.1-8.0 7.0 0.5 26

Pectoral-fin base width –2.7-3.4 3.1 0.2 26

Pre-pelvic length 70.3 70.3-76.2 74.0 1.5 27

Pre-anal length 87.7 84-89 86.2 1.2 27

Anal-fin ray length – 8.8-12.7 10.9 1.2 26

Anal-fin base length –4.2-7.5 6.0 0.9 26

Caudal-peduncle length –2.2-3.8 2.8 0.4 26

In percent of head length

Head width 65.2 56.6-71.2 62.4 3.3 27

Interorbital width 40.9 23.3-30.8 27.8 1.9 27

Nostril distance 20.1 11.1-16.2 13.7 1.5 27

Snout length 40.9 20.7-25.8 23.9 1.1 27

Eye diameter 25.6 12.6-16.3 14.3 0.9 27

Postorbital length –61.4-69.5 63.5 1.7 26

Gular length –53.5-65.9 58.0 2.9 26

Length of first spine –19.8-32.5 26.6 3.0 26

Length of second spine –25.9-34.5 30.8 2.6 26

Width : length of first spine –23.6-37.4 23.6 3.9 26

Length of second : first spine –98.4-133.7 133.7 9.2 26

Diagnosis. Polypterus mokelembembe is distin-

guished from all other species of Polypterus except

P. palmas, P. retropinnis and P. teugelsi by the

number of pre-dorsal scales (30-37 vs. 11-29); it

is distinguished from P. teugelsi and from all other

congeners except P. palmas, P. retropinnis, P. sene-

galus and P. weeksii by the number of pectoral-fin

rays (24-30 vs. 31-48). Polypterus mokelembembe is

Moritz & Britz: Revision of Polypterus

distinguished from P. teugelsi by fewer scales in

lateral series (57-61 vs. 64-65) and fewer pectoral-

fin rays (24-30 vs. 40-43). Polypterus mokelembembe

is distinguished from P. palmas and P. retropinnis

by a distinct continuous dark suborbital stripe

strongly contrasted against a plain background

(vs. suborbital stripe absent or hardly distinguish-

able from background coloration in P. palmas; and

a series of small spots rather than a continuous

suborbital stripe in P. retropinnis), dorsal half of

head with uniform grey or with slightly marbled

coloration (vs. dorsal half of head with dark grey

or brown marbling); margins of opercular and

spiracular bones clearly marked in dark grey or

almost black (vs. respective margins hardly or

not at all contrasted by coloration), and iris pure

orange without any dark speckles or stripes (vs.

grey with dark grey radial pattern in P. retropin-

nis, and white to yellow with numerous dark

spots in P. palmas, respectively). Furthermore,

P. mokelembembe differs from P. palmas in having

more pre-dorsal scales (30-37, median 35 vs.

21-31, median 26, respectively), fewer pectoral-

fin rays (24-30, median 27 vs. 30-38, median 35,

respectively) a distinct dark blotch on distal part

of pectoral-fin base (vs. absence of such blotch).

Polypterus mokelembembe differs from P. retropin-

nis by the number of pectoral-fin rays (24-30,

median 27 vs. 28-36, median 32, respectively),

color pattern of iris (uniform vs. with radial pat-

tern, respectively) and first dorsal-fin spine width

(7.2-9.8 % HL vs. 4.6-7.5, respectively).

Descriptive synopsis. Meristic and morpho-

metric data in Tables 13-14. A small species,

maximum size 261 mm SL (280 mm TL). Body

moderately elongated with dorsal fin positioned

further posteriorly. Upper jaw slightly projecting

beyond lower jaw.

Coloration. In life: dorsal half of body light grey

to brown with 5-7 large dark brown irregular

dorsolateral saddle-like bars, sometimes conflu-

ent with blotch-like ventrolateral markings and

then extending onto upper part of ventral half of

flank. Ventral half of body light: white or yellow-

ish (Fig. 33). Border between coloration of upper

and lower half of flank not conspicuous. Dorsal

half of head uniform grey or with slight dark

grey marbling on light grey background; margins

of opercular and spiracular bones marked as

prominent black lines; lower half of cheek white;

30°N

20°N

10°N

0°

10°S

30°N

20°N

10°N

0°

10°S

10°W 10°E 20°E 30°E0°

Fig. 34. Records of Polypterus mokelembembe. , type locality;

Revision of the extant Polypteridae (Actinopterygii: Cladistia)

Abstract and Figures