ArticlePDF Available

Two new species of African suckermouth catfishes, genus Chiloglanis (Siluriformes: Mochokidae), from Kenya with remarks on other taxa from the area

November 2015
Zootaxa 4044(1):45-64

DOI:10.11646/zootaxa.4044.1.2

Authors:

Ray C. Schmidt

Randolph–Macon College

Henry Bart

Tulane University

Wanja Dorothy Nyingi

National Museums of Kenya

Recent expeditions in Kenya and examination of existing collections confirmed the presence of two undescribed Chiloglanis species and revealed previously unknown diversity within the Athi River system. The two new species are easily distinguished from described congeners in the area by external morphology, allopatric distributions, and genetic markers. Chiloglanis kerioensis sp. nov., is restricted to the Kerio River system and is the only known suckermouth catfish from the Lake Turkana basin. Chiloglanis devosi sp. nov., is known only from the type locality, the Northern Ewaso Nyiro (Ng'iro) below Chanler's Falls. In addition to these two new species, this study confirmed the presence of an undescribed Chiloglanis sp. occurring sympatrically with Chiloglanis brevibarbis in the Tsavo River. A dichotomous key for identifying all described Chiloglanis species found within Kenya is presented along with comments.

Dorsal, lateral and ventral views of Chiloglanis kerioensis holotype, NMK FW/3959/1, male, 40.3 mm SL; Kenya, Rift Valley Province, Barwessa River (Barwessa Village) near Lake Kamnarok Scale bar equals 1cm. Photographs by R.C. Schmidt.

…

. Morphometric measurements and meristic counts for Chiloglanis somereni, C. deckenii, and Chiloglanis sp. aff. deckenii. Standard length expressed in mm. All other measurements expressed in percent SL. C. somereni (N=22) C. deckenii (N=15) C. sp aff. deckenii Tsavo R. (N=20)

…

Lateral views of Chiloglanis devosi showing life coloration: (A), NMK FW/2777/1-11 male, 36.0 mm SL, (B) NMK FW/2777/1-11, female, 49.0 mm SL. Scale bar equals 1cm. Photographs by H.L. Bart Jr.

…

Figures - uploaded by Ray C. Schmidt

Content may be subject to copyright.

Content uploaded by Ray C. Schmidt

Content may be subject to copyright.

Accepted by L. Page: 22 Sept. 2015; published: 17 Nov. 2015

ZOOTAXA

ISSN 1175-5326 (print edition)

ISSN

1175-5334

(online edition)

Zootaxa 4044 (1): 045

–

064

www.mapress.com

zootaxa

Article

http://dx.doi.org/10.11646/zootaxa.4044.1.2

http://zoobank.org/urn:lsid:zoobank.org:pub:9E1A791F-650C-4ED8-AEB1-6325B1FB3409

Two new species of African suckermouth catfishes, genus Chiloglanis

(Siluriformes: Mochokidae), from Kenya with remarks on other taxa

from the area

RAY C. SCHMIDT

, HENRY L. BART JR

& WANJA DOROTHY NYINGI

Department of Ecology and Evolutionary Biology, Tulane University, New Orleans, LA 70118; Present affliation: Smithsonian Mpala

Postdoctoral Fellow, Mpala Research Centre, PO Box 555-10400- Nanyuki, KENYA

Department of Ecology and Evolutionary Biology, Tulane University, New Orleans, LA 70118;

Tulane University Biodiversity Research Institute, Belle Chasse, LA 70037

Ichthyology Section, National Museums of Kenya, PO Box 40658-00100- Nairobi, KENYA

Abstract

Recent expeditions in Kenya and examination of existing collections confirmed the presence of two undescribed Chilogl-

anis species and revealed previously unknown diversity within the Athi River system. The two new species are easily dis-

tinguished from described congeners in the area by external morphology, allopatric distributions, and genetic markers.

Chiloglanis kerioensis sp. nov., is restricted to the Kerio River system and is the only known suckermouth catfish from

the Lake Turkana basin. Chiloglanis devosi sp. nov., is known only from the type locality, the Northern Ewaso Nyiro

(Ng’iro) below Chanler’s Falls. In addition to these two new species, this study confirmed the presence of an undescribed

Chiloglanis sp. occurring sympatrically with Chiloglanis brevibarbis in the Tsavo River. A dichotomous key for identify-

ing all described Chiloglanis species found within Kenya is presented along with comments.

Key words: Chiloglanis deckenii Peters 1868, Chiloglanis somereni Whitehead 1958, Lake Victoria, East Africa

Introduction

Species of the genus Chiloglanis Peters 1868 inhabit most tropical rivers throughout sub-Saharan Africa and the

Nile River basin. With approximately 49 valid species, and more awaiting formal description, Chiloglanis is the

second largest genus within the family Mochokidae. Classified in the subfamily Chiloglanidinae (Riehl & Baensch

1991; Vigliotta 2008; Friel & Vigliotta 2011), these species possess distinctive oral discs that allow them to feed

and maintain their position in flowing waters.

From 2010 through 2012 populations of suckermouth catfishes and other fishes were collected across Kenya in

connection with a National Science Foundation International Research Experience for Students (IRES) grant

awarded to Tulane University. Three recognized species of Chiloglanis are reported from the freshwaters of Kenya

(Seegers et al. 2003, Schmidt et al. 2014). Chiloglanis deckenii Peters 1868 occurs in the Pangani River basin of

southern Kenya and northern Tanzania. Chiloglanis brevibarbis Boulenger 1902 occurs throughout the Tana River

basin and Athi River system within central Kenya. Chiloglanis somereni Whitehead 1958 inhabits streams of the

Lake Victoria basin in western Kenya. Two other species, previously discovered, have not been taxonomically

described (Seegers et al. 2003; Schmidt et al. 2014). One of these species inhabits the headwaters of the Kerio

River, which flows into Lake Turkana in northern Kenya; the other is found in the Northern Ewaso Nyiro (Ng’iro)

below Chanler’s Falls (Seegers et al. 2003; Schmidt et al. 2014). Collected specimens and existing museum

collections provide comparative material for a morphological analysis of the Kenyan Chiloglanis and formal

descriptions of the two previously known but undescribed species. A key for the described Kenyan Chiloglanis,

including species described herein, and notes on distribution and biology of each species are also presented.

SCHMIDT ET AL.

Material and methods

Chiloglanis specimens were collected across Kenya during three expeditions (Fig. 1). These specimens and

additional National Museum of Kenya (NMK) collections are included in this analysis. Measurements were taken

to 0.1 mm with a digital caliper or with a dissection scope equipped with an ocular micrometer. Morphometric

measurements of the head and body follow Friel and Vigliotta (2011).

Meristic count formulas follow Skelton and White (1980) and Friel and Vigliotta (2011); however, our

terminology for premaxillary teeth differs slightly. We consider the primary premaxillary teeth to be restricted to

the two ovoid tooth patches; tertiary teeth are restricted to the dorsal edge of the tooth plate; secondary

premaxillary teeth are scattered across the space between the primary and tertiary premaxillary teeth. Gender of

type specimens was determined by external examination of the genital papillae following described methods (Friel

& Vigliotta 2011; JP Friel pers. comm.). Principal components analysis and summary statistics were completed in

MYSTAT 12 (SYSTAT Software, Inc.). Institutional abbreviations follow Sabaj Perez (2010).

FIGURE 1. Collection localities of Chiloglanis specimens included in this study and type localities of new species described

herein: Chiloglanis deckenii (triangle), C. brevibarbis (circle), C. somereni (square), C. kerioensis (type locality—asterisk,

paratypes—cross), and C. devosi (type locality—star). Drainage boundaries denoted by white lines.

TWO NEW CHILOGLANIS FROM KENYA

Morphological results

The principal components analysis (PCA) of the residuals from 45 morphometric measurements regressed against

standard length from 169 specimens distinguished the three previously known Chiloglanis species and the two new

species described herein (Fig. 2). The groups revealed by the PCA correspond to those discovered in previous

phylogenetic analysis (Schmidt et al. 2014). Principal component (PC) 1 accounts for 19.2% of overall variation.

Oral disc length, prepectoral length, and dorsal spine length contributes most to the variation observed along PC1

(Tables 1

–

4). PC2 accounts for 15.4% of overall variation with orbit diameter, occipital shield width, adipose fin

height, and length of postcleithral process contributing the most to observed variation.

While most of the species are non-overlapping there is overlap between C. devosi and C. somereni, and

between Chiloglanis sp. aff. deckenii and C. brevibarbis. Morphological variation is observed among C.

brevibarbis populations, but there is much overlap. Chiloglanis sp aff. deckenii specimens from the Tsavo River are

morphologically similar to C. brevibarbis. Body measurements of these specimens’ allies them with C. brevibarbis

while the morphology of the oral disc and mouth parts are closer to C. deckenii. Measurements for C. somereni, C.

brevibarbis, C. deckenii, and Chiloglanis sp. aff. deckenii are summarized in Tables 3 and 4.

FIGURE 2. Plot of PC1 to PC2 from principal components analysis of the residuals of 45 linear measurements regressed

against standard length of 169 Chiloglanis specimens. Polygons outline individuals from each species or population. Two new

Chiloglanis species are outlined in bold with holotypes (star). The undescribed taxon from the Tsavo River is outlined in hash

line. Measurements contributing most to variation along PC1 and PC2 are shown.

Chiloglanis kerioensis sp. nov.

Figs. 1, 3; Table 1

Chiloglanis spec. “Kerio”

—

Seegers et al. 2003: 38.

Chiloglanis sp. “Kerio River”

—

Schmidt et al. 2014: 416, 419.

SCHMIDT ET AL.

Holotype. NMK FW/3959/1, male ALC, 40.3 mm SL; Kenya, Rift Valley Province, Barwessa River (Barwessa

Village) near Lake Kamnarok, Georeferenced: 00.63505° N, 35.618126° E; L. De Vos, 4 January 1999.

Paratypes. NMK FW/599/1-13, 9 ALC, 32.1–37.6 mm SL; same collection data as holotype.—NMK FW/

2794/1-6, 6 ALC, 27.4–38.4 mm SL; same collection data as holotype.—TU 204096, 3 ALC, 32.6–35.9 mm SL;

same collection data as holotype.—NMK FW/2243/1-24, 21 ALC, 27.6–32.9 mm SL; tissue vouchers: IRES

1514—IRES 1517; Kenya, Rift Valley Province, Kerio Rift near Chebloch Gorge, off Kabernet—Tambach Rd.

(C51), 00.45017° N, 35.64670° E, 2011 IRES team, 23 June 2011.—TU 204094, 3 ALC, 29.7–31.1 mm SL; same

collection data as NMK FW/2243/1-24.

Diagnosis. Chiloglanis kerioensis is distinguished from C. somereni and C. devosi in having fewer mandibular

teeth (eight or fewer versus eight or more) and a larger orbit (>4% SL versus <4% SL). Chiloglanis kerioensis is

distinguished from C. brevibarbis by longer barbels (maxillary barbels usually >30% HL versus <30% HL, medial

mandibular barbels >10% HL versus <9% HL, and lateral mandibular barbels >17% HL versus <15% HL) and in

the arrangement of the mandibular teeth (exposed length of teeth not equal to row width versus exposed portion

equal or greater than row width in C. brevibarbis populations). Chiloglanis kerioensis differs from C. deckenii in

having a longer premaxillary tooth pad (>3% SL versus <3% SL) and longer lower lip (>60% HL versus <55%

HL). The species is distinguished from Chiloglanis sp. aff deckenii by the following combination of characters: C.

kerioensis has a longer postcleithral process (>9% SL versus <9% SL) and longer lateral mandibular barbels

(>15% HL versus >15% HL).

Description. Morphometric measurements and meristics for holotype and paratypes of C. kerioensis are

summarized in Table 1. Dorsal, lateral, and ventral views (Fig. 3) illustrate body shape, fin shape and placement,

oral disc shape and size, and barbel length.

A small, relatively deep-bodied Chiloglanis, maximum standard length observed 40.3 mm. Body dorsally

depressed anteriorly and laterally compressed posteriorly. Predorsal angled towards snout. Pre-orbital convex.

Postdorsal body angled ventrally towards caudal fin. Preanal profile horizontal; postanal sloping dorsally towards

caudal fin. Skin with numerous small unculiferous (horny unicellular projections) tubercles, body uniformly

covered with higher concentrations of more pronounced tubercles in the head region. Lateral line complete, arising

slightly above horizontal to orbit and sloping ventrally to midlateral alongside of body. Urogenital papillae

elongate in males; reduced and separated from anus by shallow invagination in females.

Head broadly depressed. Gill openings restricted, from level of pectoral fin attachment to middle of eye. Gill

membranes broadly united. Occipital-nuchal shield covered and visible through skin. Eyes small, horizontal axis

longest, orbit without free margin. Anterior and posterior nares positioned mid-snout length and equidistant. Nares

with raised rim, posterior nares with elongated anterior and medial flaps. Mouth inferior, upper and lower lips

united to form sucking disc. Oral disc moderate in size, wider than long and covered in papillae. Barbels in three

pairs; maxillary barbel originating from posterolateral region of the disc, unbranched, long, reaching 45% of head

length. Lateral and medial mandibular barbels moderate, lateral barbels twice the length of medial barbels,

incorporated into lower lip and positioned on both sides of prominent midline cleft on the posterior margin of disc.

Primary maxillary teeth numerous (36–80), “S” shaped with exposed tips light brown in color, arranged in

three rows on oval shaped tooth. Secondary premaxillary teeth fewer in number and scattered on posterior surface

of premaxillae. Tertiary teeth small and needle-like, inserted near midline on dorsal edge of toothplate. Mandibular

teeth arranged in one to two rows, “S” shaped, grouped near midline. The anterior row (functional row) supporting

–

8 brown tipped sharp teeth.

Dorsal fin originates in anterior third of body. Dorsal fin with small spinelet, spine and 6 rays. Dorsal spine

short, anterior margins of spine marked with 2 small notches distally, posterior margins smooth. Adipose fin

moderate in length, length into SL four to five times; margin convex with a small incision posteriorly. Caudal fin

forked with gently pointed lobes, lower lobe slightly longer than upper lobe, count i, 7, 8, i. Anal fin extending

beyond adipose fin terminus, count iii, 8. Pelvic fin origin at vertical between dorsal and adipose fin, margins

convex, count i, 6. Pectoral fin with slightly curved smooth spine, moderate in length, five to six times into

standard length, count i, 8–9. Post cleithral process going into standard length nine to ten times, buried under the

skin. No apparent sexual dimorphism in shape or size of fins. Dimorphism of body size apparent with females

being the largest specimens collected.

Coloration. Live coloration: Body with yellowish-brown ground color with overlying melanophores and gold

iridescent flecks alongside of body. Fins yellow to orange. Typical coloration of preserved specimens is shown in

TWO NEW CHILOGLANIS FROM KENYA

Figure 3. In dorsal view, specimens appear medium brown with three light bands. The first lies anterior to the

dorsal fin; second and third bands are anterior and posterior to the adipose fin. Lighter spots visible along sides

above lateral line. Head uniformly medium brown.

In lateral view, specimens have cream-buff ground color with overlying medium brown above lateral line and

cream to yellow from lateral line to belly. Three light bands observed from above extend beyond midline. Light

spots on sides above and below lateral line, light areas on lateral line extending dorsally. Numerous small black

melanophores scattered across sides, more concentrated below lateral line.

Ventral surface yellow to cream colored. Small melanophores near origin of pelvic fins and around anal fin.

Oral disc and barbels yellow to cream colored.

FIGURE 3. Dorsal, lateral and ventral views of Chiloglanis kerioensis holotype, NMK FW/3959/1, male, 40.3 mm SL; Kenya,

Rift Valley Province, Barwessa River (Barwessa Village) near Lake Kamnarok Scale bar equals 1cm. Photographs by R.C.

Schmidt.

SCHMIDT ET AL.

Etymology. The specific epithet refers to the Kerio River, Lake Turkana basin, where the species is believed to

be endemic.

Distribution. This species is known from two localities in the upper Kerio River system (the type locality on

Barwessa River (asterisk, Fig. 1) and in the Kerio River at Chebloch Gorge (cross, Fig. 1)) and is likely endemic to

the system. This species was abundant in the medium rapids upstream from the road crossing (Chebloch Gorge)

and were aggregated near the larger boulders. It is likely that further sampling efforts within the upper Kerio River

system will reveal addition populations.

TABLE 1. Morphometric measurements and meristic counts for Chiloglanis kerioensis (N=43; holotype and 42

paratypes). Standard length expressed in mm. All other measurements expressed in percent SL. Meristic data for

holotype are identified by a “*”.

MORPHOMETRICS Holotype Range Mean±%SD

Standard length (mm) 40.3 27.4–40.3

Head length 29.5 27.6–33.1 30.6±1.3

Head depth (maximum) 18.4 13.8–19.6 16.3±1.5

Body depth at anus 15.4 12.1–19.1 14.4±1.6

Occipital shield width (minimum) 3.6 3.6–4.7 4.2±1.3

Prepectoral length 29.6 28.5–34.1 31.2±1.3

Predorsal length 42.0 40.2–44.5 42.0±1.1

Prepelvic length 56.5 53.3–57.3 55.7±1.4

Preanal length 70.8 67.2–74.9 71.1±1.6

Eye diameter (horizontal) 4.3 3.9–5.3 4.5±0.3

Orbital interspace 7.6 6.9–8.8 7.7±0.5

Snout length 18.9 15.8–20.1 18.4±0.9

Premaxillary tooth-patch width 13.2 12.4–16.0 14.0±0.9

Premaxillary tooth-patch length 3.5 3.0–4.3 3.6±0.3

Mandibular tooth row width 2.1 1.3–2.7 2.4±0.3

Anterior nares interspace 4.5 3.8–5.3 4.7±0.3

Posterior nares interspace 4.4 3.8–5.4 4.7±0.4

Maxillary barbel length 9.8 8.5–13.4 11.7±1.1

Medial mandibular barbel length 3.2 2.5–4.2 3.3±0.4

Lateral mandibular barbel length 6.0 4.5–7.1 5.9±0.5

Mouth width 9.1 8.3–10.3 9.2±0.5

Oral disc width 19.0 18.1–23.0 20.3±1.1

Oral disc length 18.2 17.4–21.4 19.4±1.0

Upper lip length 4.1 3.1–5.2 4.0±0.4

Lower lip length 7.6 6.1–8.7 7.7±0.6

Pectoral-spine length 16.6 16.4–21.4 18.7±1.2

Pectoral-fin length 22.0 19.3–24.7 21.9±1.5

Width at pectoral-fin insertion 24.0 23.0–28.2 25.0±1.0

Length of postcleithral process 11.9 9.3–13.3 10.9±0.9

Pelvic-fin length 14.9 12.4–16.8 14.5±1.0

Depth at dorsal-fin insertion 20.9 14.6–25.0 18.9±2.3

Dorsal-spine length 12.7 12.2–16.1 14.5±1.1

Dorsal-fin length (longest ray) 17.7 16.3–20.4 18.1±1.0

Dorsal-fin base length 10.1 9.9–13.9 11.9±1.0

......continued on the next page

TWO NEW CHILOGLANIS FROM KENYA

Chiloglanis devosi sp. nov.

Figs. 1, 4, 5; Table 2

Chiloglanis spec. “Northern Ewaso Nyiro”—Seegers et al. 2003: 38.

Chiloglanis sp. “Northern Ewaso Nyiro”—Schmidt et al. 2014: 416, 419.

Holotype. NMK FW/3958/1, male ALC, 36.0 mm SL; Kenya, Eastern Province, Northern Ewaso Nyiro (Ewaso

Ng’iro) below Chanler’s Falls, Isiolo—Merti Road, 00.78056° N, 38.08021° E; 2012 IRES team, 12 June 2012.

Paratypes. NMK FW/2777/1-11, 8 ALC, 34.0–49.2 mm SL; tissue vouchers: IRES 10051—IRES 10053;

same collection data as holotype.—TU 204093, 2 ALC, 35.1–52.5 mm SL; same collection data as holotype.

Diagnosis. Chiloglanis devosi is distinguished from C. somereni by having shorter dorsal spines (12.3–17.2%

SL versus 17.9–23.0% SL) and having the anterior and posterior nares the same distance apart (versus posterior

nares further apart in C. somereni). Chiloglanis devosi is easily distinguished from the other Kenyan congeners in

having a wider occipital shield width (>5% SL versus <5% SL), more mandibular teeth (eight or more versus 8 or

fewer), and a smaller orbit (<4% SL versus >4% SL).

Description. Morphometric measurements and meristics for holotype and paratypes of C. devosi are

summarized in Table 2. Dorsal, lateral, and ventral views (Figs. 4 & 5) illustrate body shape, fin shape and

placement, oral disc shape and size, and barbel length.

Moderate to small sized Chiloglanis, maximum standard length observed 49.2 mm. Body dorsally depressed

anteriorly and laterally compressed posteriorly. Predorsal convex, post-orbital slightly so, pre-orbital sharply

convex. Postdorsal body sloping ventrally towards caudal fin. Preanal profile horizontal; postanal sloping dorsally

towards caudal fin. Skin with numerous small unculiferous tubercles, body uniformly covered with higher

TABLE 1. (Continued)

MORPHOMETRICS Holotype Range Mean±%SD

Dorsal fin to adipose-fin length 15.7 13.6–21.1 16.6±1.8

Adipose-fin base length 22.5 18.0–24.4 21.3±1.4

Adipose fin to caudal-ped length 13.6 10.3–14.5 12.3±0.9

Adipose-fin height 4.3 2.7–5.4 4.4±0.6

Anal-fin length (longest ray) 14.1 13.4–19.6 15.8±1.2

Anal-fin base length 11.6 9.8–13.6 12.0±1.0

Lower caudal-fin lobe length 28.3 26.4–33.4 29.2±1.7

Upper caudal-fin lobe length 27.1 23.7–32.0 27.2±1.7

Fork Length 13.6 12.5–16.5 14.4±1.0

Caudal-peduncle depth (maximum) 10.8 9.1–12.0 10.7±0.7

Caudal-peduncle length 16.6 13.6–17.4 15.2±0.9

Meristics

Mandibular tooth rows 1,2

Mandibular tooth count (total) 6–16; 8*

Mandibular tooth count (functional anterior row) 6–8; 8*

Mandibular tooth count (posterior replacement row) 1–8;

Primary premaxillary teeth (total) 36–80; 56*

Pectoral-fin count I, 8*(37); I, 9(6)

Pelvic-fin count i, 6*(43)

Dorsal-fin count II, 6 (43)

Anal-fin count iii, 7(1); iii, 8*(10)

Caudal-fin count i, 7, 8, i* (43)

SCHMIDT ET AL.

concentrations in the head region. Lateral line complete, arising horizontal to orbit and sloping ventrally to

midlateral alongside of body. Urogenital papillae elongate in males; reduced and separated from anus by shallow

invagination in females.

Head depressed. Gill openings restricted, from level of pectoral fin attachment to middle of eye. Gill

membranes broadly united. Occipital-nuchal shield covered and visible through skin. Eyes small, horizontal axis

longest, orbit without free margin. Anterior and posterior nares positioned mid-snout length and equidistant. Nares

with raised rim, posterior nares with elongated anterior flaps.

Mouth inferior, upper and lower lips united to form sucking disc. Oral disc moderate in size, slightly wider

than long and covered in papillae. Barbels in three pairs; maxillary barbel originating from posterolateral region of

the disc, unbranched, moderate in length, reaching 25% of head length. Lateral and medial mandibular barbels

short, one-third length of maxillary barbel, and incorporated into lower lip. Mandibular barbels positioned on both

sides of prominent midline cleft on the posterior margin of disc; medial mandibular barbel adjacent to cleft and

lateral mandibular barbel just lateral to medial barbel.

Primary maxillary teeth numerous (51–81), “S” shaped with exposed tips brown in color, arranged in three

scattered rows on kidney-shaped patched on ventral surface. Secondary premaxillary teeth fewer in number and

scattered on posterior surface of premaxillae. Tertiary teeth small and needle-like, inserted near midline on dorsal

edge of toothplate. Mandibular teeth arranged in one to two rows, “S” shaped and crowded at midline. The anterior

row (functional row) supporting 7–12 brown tipped sharp teeth.

Dorsal fin origin in anterior third of body. Dorsal fin with small spinelet, spine and 4–6 rays. Dorsal spine long,

nearly half as long as head length. Anterior margins of spine marked with three small notches distally, posterior

margins smooth. Adipose fin moderate in length, length into SL four times; margin convex and slightly incised

posteriorly. Caudal fin forked with rounded lobes, lower lobe slightly longer than upper lobe, count i, 7, 8, i. Anal

fin sexually dimorphic; males displaying elongated rays that extend well beyond terminus of adipose fin, margin

convex, count iii, 8. Pelvic fin origin at vertical between dorsal and adipose fin, margins convex, count i, 6.

Pectoral fin with slightly curved smooth spine, moderate in length, count i, 8–9. Post cleithral process elongate,

going into standard length ten times, buried under the skin. Body dimorphism present with females attaining larger

sizes than males.

FIGURE 4. Lateral views of Chiloglanis devosi showing life coloration: (A), NMK FW/2777/1-11 male, 36.0 mm SL, (B)

NMK FW/2777/1-11, female, 49.0 mm SL. Scale bar equals 1cm. Photographs by H.L. Bart Jr.

TWO NEW CHILOGLANIS FROM KENYA

FIGURE 5. Dorsal, lateral and ventral views of Chiloglanis devosi holotype, NMK FW/3958/1, male, 36.0 mm SL; Kenya,

Eastern Province, Northern Ewaso Nyiro (Ewaso Ng’iro) below Chanler’s Falls, Isiolo—Merti Road, 00.78056° N, 38.08021°

E. Scale bar equals 1cm. Photographs by R.C. Schmidt.

Coloration. Live coloration of this species shown in Figure 4. Body with pinkish brown ground color with

overlying melanophores that produces the pattern observed in preserved specimens. Iridescent gold markings along

sides of body, large iridescent gold area dorsal and posterior to pectoral fin origin with smaller gold markings on

side of body, dorsal of lateral line. Fins yellows with brown markings. Typical coloration of preserved specimens is

shown in Figure 5. In dorsal view, specimens appear medium brown with three distinct areas of light brown to

cream coloration. The first lies anterior to the dorsal fin; second and third bands are anterior and posterior,

respectively, to the adipose fin. Lighter spots visible along sides of dorsal fin above lateral line. Head medium

brown with areas of mottled lighter brown.

In lateral view, specimens with cream-buff ground color with medium brown present along sides and above

lateral line. Cream-buff ground color anterior to dorsal fin extends to lateral line, dark area anterior to adipose fin

extends onto side below lateral line, and the light area posterior to adipose fin extends through caudal peduncle,

giving the peduncle a depigmented appearance. Light spots on sides above and along lateral line. Numerous small

black melanophores scattered across sides, more concentrated posteriorly and below lateral line.

Ventral surface cream colored. Few melanophores near origin of pelvic fins and around anal fin. Oral disc and

barbels yellow to cream colored.

SCHMIDT ET AL.

Etymology. We take pleasure in naming this species in honor of Dr. Luc DeVos, the late ichthyologist and

director of the Ichthyology Section at the National Museums of Kenya. Dr. DeVos was instrumental in establishing

the collection at NMK and building it into a regional and internationally invaluable collection. DeVos and others

(Seegers et al. 2003) were also responsible for discovering and recognizing both new species described herein as

distinct.

Distribution. This species is only known from the type locality (below Chanler’s Falls on the Northern Ewaso

Nyiro River (Fig. 1)). Specimens were collected around rocks and small boulders in flowing water. Additional

populations on this species may occur in favorable habitats downstream from Chanler’s Falls and within tributaries

that join the Northern Ewaso Nyiro until the river flows into the largely endorheic Lorian Swamp (Fig. 1).

TABLE 2. Morphometric measurements and meristic counts for Chiloglanis devosi (N=11; holotype and 10 paratypes).

Standard length expressed in mm. All other measurements expressed in percent SL. Meristic data for holotype are

identified by a “*”.

MORPHOMETRICS Holotype Range Mean±%SD

Standard length (mm) 36.0 34.0–49.2

Head length 30.1 30.1–34.7 32.2±1.4

Head depth (maximum) 14.5 14.5–17.4 15.5±1.0

Body depth at anus 13.5 13.1–16.8 14.4±1.3

Occipital shield width (minimum) 5.7 5.5–7.1 5.9±0.5

Prepectoral length 30.6 28.2–32.7 30.4±1.2

Predorsal length 39.0 36.7–42.0 39.8±1.6

Prepelvic length 55.5 52.1–59.4 56.3±1.9

Preanal length 70.2 68.1–72.0 69.7±1.3

Eye diameter (horizontal) 3.3 3.0–3.9 3.5±0.3

Orbital interspace 7.3 7.3–8.6 8.0±0.4

Snout length 18.1 17.2–19.7 18.8±0.7

Premaxillary tooth-patch width 13.0 13.0–15.3 14.5±0.7

Premaxillary tooth-patch length 3.7 3.3–4.3 3.8±0.3

Mandibular tooth row width 2.9 2.4–3.9 3.0±0.5

Anterior nares interspace 4.6 3.9–5.6 4.5±0.4

Posterior nares interspace 4.4 3.4–4.8 4.2±0.4

Maxillary barbel length 8.7 3.0–9.8 7.5±1.8

Medial mandibular barbel length 2.4 1.8–3.0 2.2±0.4

Lateral mandibular barbel length 3.7 3.0–4.9 3.8±0.6

Mouth width 10.7 10.1–12.6 11.2±0.8

Oral disc width 20.5 19.7–23.7 21.8±1.1

Oral disc length 19.7 18.7–21.8 20.2±1.1

Upper lip length 4.4 3.9–5.4 4.5±0.4

Lower lip length 8.9 5.2–10.3 8.8±1.4

Pectoral-spine length 17.7 15.6–21.4 18.8±1.8

Pectoral-fin length 21.3 19.3–22.2 20.6±1.0

Width at pectoral-fin insertion 23.3 23.0–25.3 23.6±0.7

Length of postcleithral process 8.9 8.9–12.3 10.5±0.9

Pelvic-fin length 22.0 11.3–22.0 13.6±3.0

Depth at dorsal-fin insertion 15.5 15.3–18.5 16.6±1.0

......continued on the next page

TWO NEW CHILOGLANIS FROM KENYA

Key to Chiloglanis species from Kenya

1. Usually more than eight mandibular teeth in functional (anterior) row; minimum occipital shield width > 5% SL; eye small,

orbit diameter < 4% SL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

- Eight or fewer mandibular teeth in functional row; minimum occipital shield width < 5% SL; eye larger, orbit diameter > 4% SL

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

2. Spines long, dorsal and pectoral spine combined >40% SL; anterior nares distinctly further apart than posterior nares . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Chiloglanis somereni (Lake Victoria basin)

- Spines shorter, dorsal and pectoral spine combined <36% SL; anterior nares set same distance apart as posterior nares or nearly

so . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Chiloglanis devosi (Northern Ewaso Nyiro (Ng’iro))

3. Mandibular teeth elongate (exposed length of teeth into row width once), two rows usually visible, strongly decurved and

bunched at symphysis; premaxillary teeth pads ovoid and large with 4–5 rows of teeth (juveniles may have less than 4); oral

disc usually as long as wide or nearly so; lateral barbels rarely twice as long as medial barbels. . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Chiloglanis brevibarbis (Athi and Tana R.)

- Mandibular teeth shorter (exposed length of teeth going into row width more than once); premaxillary pads rectangular and

small with less than 4 rows of premaxillary teeth; oral disc usually not as long as wide; lateral barbels usually twice as long as

medial barbels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

4. Premaxillary tooth patch length >3% SL and postcleithral process long (>9 % SL) . . . . . .Chiloglanis kerioensis (Kerio River)

- Premaxillary tooth patch length <3% SL (if >3% SL, length of postcleithral process <9% SL) . . . . . . . . . . . . . . . . . . . . . . . . . 5

5. Short snout (16.9–18.6% SL); oral disc smaller and distinctively wider (14.9–20.4% SL) than long (13.4–16.1% SL); premax-

illary teeth pads more rectangular with length (2.4–3.3% SL) with 3 rows of deeply embedded teeth . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Chiloglanis deckenii (Pangani R.)

- Moderate snout (18.0–22.0% SL); oral disc larger and slightly more wide (18.2–22.4% SL) than long (16.8–21.2% SL); pre-

maxillary teeth pads more ovoid with length (2.6–3.5% SL) with 3–4 rows of partially embedded teeth. . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Chiloglanis sp. aff. deckenii (Tsavo River)

TABLE 2. (Continued)

MORPHOMETRICS Holotype Range Mean±%SD

Dorsal-spine length 14.4 12.3–17.2 15.0±1.3

Dorsal-fin length (longest ray) 16.3 14.2–17.0 16.0±0.8

Dorsal-fin base length 12.2 10.5–12.7 11.7±0.6

Dorsal fin to adipose-fin length 14.9 11.0–17.8 15.2±2.3

Adipose-fin base length 23.3 20.6–27.1 24.0±2.2

Adipose fin to caudal-ped length 14.7 11.4–16.7 14.3±1.5

Adipose-fin height 4.1 2.9–4.2 3.6±0.4

Anal-fin length (longest ray) 16.3 14.0–18.5 15.9±1.2

Anal-fin base length 12.6 9.5–14.1 11.6±1.4

Lower caudal-fin lobe length 26.5 25.1–27.5 26.2±0.8

Upper caudal-fin lobe length 23.7 21.3–25.9 23.6±1.4

Fork Length 15.5 12.6–16.7 15.0±1.4

Caudal-peduncle depth (maximum) 10.7 10.2–11.3 10.8±0.4

Caudal-peduncle length 19.2 16.7–19.7 18.2±1.1

MERISTICS

Mandibular tooth rows 2

Mandibular tooth count (total) 10–16; 11*

Mandibular tooth count (functional anterior row) 7–15; 9*

Mandibular tooth count (posterior replacement row) 2–6; 2*

Primary premaxillary teeth (total) 51–81; 63*

Pectoral-fin count I, 8*(10); I, 9(1)

Pelvic-fin count i, 6*(11)

Dorsal-fin count II, 4(1); II, 5(4); II, 6*(6)

Anal-fin count iii, 7(1); iii, 8*(10)

Caudal-fin count i, 7, 8, i*(11)

SCHMIDT ET AL.

Discussion

The diminutive nature and superficially similar morphology of the suckermouth catfishes, along with the paucity of

comparative material, has contributed to taxonomic confusion across this group. Though seemingly similar, here

we show that it is possible to distinguish Kenyan species by comparing multiple morphological characters. In

addition to the diagnostic morphological characters described herein, genetic divergence (Schmidt et al. 2014), and

allopatric distributions support recognizing C. kerioensis and C. devosi as valid species. These findings validate

previous statements that these populations required formal description (Seegers et al. 2003).

In addition to the two new species now formally described, this study confirmed the existence of a

sympatrically occurring undescribed species within the Tsavo River (Schmidt et al. 2014). This taxon is

morphologically intermediate of C. deckenii and C. brevibarbis (Tables 3, 4), though more similar in morphology

to C. brevibarbis (Fig. 2). Although it is difficult to distinguish these co-occurring taxa, the morphology of the oral

disc and teeth are informative in separating the two species. Additional material from the Tsavo River and other

localities in the middle Athi River are needed to further quantify the characteristics of this species. The additional

samples may also help us to understand how the two sympatrically occurring species are segregating ecologically.

Genetically more similar to C. deckenii (Schmidt et al. 2014), the species likely gained access to the Tsavo River

from the Pangani River basin through headwater capture. Genetic evidence of recent biotic dispersal of Pangani

River taxa into the Athi River system was also obtained for Garra and Amphilius collected in the IRES project

(unpublished data).

Through recent collection efforts we were able sample all reported species and populations of Chiloglanis

species from Kenya and deposit much needed study material in the fish collection at NMK. Additional collections

are needed in northwestern Kenyan and below Chanler’s Falls to further understand the distribution of

suckermouth catfishes in Kenya. In northwestern Kenya, the Lake Turkana tributaries that arise on the slope of Mt.

Elgon remain poorly studied (Fig. 1). These mountain fed streams, including the Suam River and upper reaches of

the Turkwell River, may provide habitat for rheophilic species like Chiloglanis. We would also like to collect

additional populations of C. devosi. However, travel to the area below Chanler’s Falls is logistically difficult. The

new Chiloglanis species described herein are the first of several new taxa destined to be described as a result of our

fruitful collaboration in the IRES project. Future discoveries and species descriptions should help us to establish

general patterns of vicariance and area relationships across sampled regions of Kenya.

Remarks on other Kenyan Chiloglanis

Recent collections, although certainly not exhaustive or geographically complete, enabled us to collect specimens

and genetic material from all described Chiloglanis species that occur within Kenya. The following comments on

species distributions and distinguishing characters are provided from these collections and existing museum

material.

Chiloglanis deckenii Peters 1868

Within Kenya, Chiloglanis deckenii only occurs in the Pangani River basin (Fig. 1). It is likely restricted to the

Pangani River basin in Tanzania but a similar species is reported to occur within the Wami and Rufiji Rivers to the

south (Seegers 2008). This species was collected in large numbers in the Lumi River (Lake Jipe affluent) near

rocks in fast flowing water. This species is distinguished from other Kenyan suckermouth catfishes in having long

mandibular barbels and an oral disc that is distinctly wider than long (Fig 5). Morphometric measurements and

meristic counts of Kenyan C. deckenii are found in Table 3.

TWO NEW CHILOGLANIS FROM KENYA

TABLE 3. Morphometric measurements and meristic counts for Chiloglanis somereni,C. deckenii, and Chiloglanis sp. aff. deckenii. Standard length

expressed in mm. All other measurements expressed in percent SL.



C. somereni (N=22) C. deckenii (N=15) C. sp aff. deckenii Tsavo R. (N=20)

MORPHOMETRICS Range Mean±%SD Range Mean±%SD Range Mean±%SD

Standard length (mm) 42.6–68.0 28.0–62.2 33.1–48.6

Head length 27.3–31.8 29.5±1.3 26.6–31.5 28.5±1.4 29.0–32.8 30.8±1.0

Head depth (maximum) 14.3–17.9 15.8±1.0 16.0–21.1 18.0±1.4 14.7–17.9 16.2±1.0

Body depth at anus 11.9–15.0 13.9±0.7 15.1–19.8 16.9±1.4 13.8–17.6 15.8±1.1

Occipital shield width (minimum) 5.5–7.0 6.4±0.5 3.9–5.4 4.6±0.4 3.0–4.8 3.8±0.4

Prepectoral length 27.4–30.1 28.9±0.7 26.0–29.1 27.8±0.9 27.9–32.0 29.7±1.1

Predorsal length 38.0–42.5 40.3±1.2 36.4–40.6 38.5±1.2 38.4–43.0 40.7±1.4

Prepelvic length 55.0–60.2 57.4±1.4 53.8–61.4 57.2±1.7 55.9–63.2 58.1±2.0

Preanal length 68.6–74.4 70.9±1.5 66.8–72.3 69.7±1.8 68.9–76.3 7.1±1.8

Eye diameter (horizontal) 3.4–4.5 3.8±1.1 3.8–5.5 4.2±0.5 3.8–5.1 4.4±0.3

Orbital interspace 7.3–8.6 8.0±0.4 6.3–7.9 7.0±0.5 5.5–7.8 7.0±0.6

Snout length 15.7–20.5 18.4±1.2 16.9–18.6 17.9±0.5 18.0–22.0 19.4±1.0

Premaxillary tooth-patch width 10.0–14.1 11.5±1.0 10.2–14.0 12.3±1.1 11.6–15.1 12.7±0.9

Premaxillary tooth-patch length 2.0–3.6 2.8±0.4 2.1–2.9 2.5±0.3 2.6–3.5 3.1±0.2

Mandibular tooth row width 1.9–2.6 2.2±0.2 1.5–2.6 2.0±0.4 1.6–2.6 1.9±0.3

Anterior nares interspace 3.6–5.1 4.4±0.4 3.4–4.8 3.8±0.4 3.8–5.4 4.5±0.4

Posterior nares interspace 3.1–4.3 3.7±0.4 3.5–4.8 4.0±0.4 3.8–5.1 4.4±0.3

Maxillary barbel length 7.5–11.9 9.5±1.3 7.8–11.5 9.4±0.9 6.8–11.0 9.1±1.1

Medial mandibular barbel length 2.1–3.7 2.9±0.5 2.0–3.3 2.7±0.4 1.5–3.3 2.7±0.5

Lateral mandibular barbel length 3.4–5.0 4.1±0.4 4.0–5.6 5.1±0.4 3.2–5.9 4.4±0.6

Mouth width 7.7–10.9 9.0±1.0 7.1–8.9 8.0±0.6 6.4–10.8 8.6±1.0

Oral disc width 17.4–21.5 19.4±1.2 14.9–20.4 17.6±1.3 18.2–22.4 19.8±1.3

Oral disc length 17.1–20.9 18.8±1.1 13.4–16.1 14.9±0.8 16.8–21.2 18.7±1.1

Upper lip length 3.7–6.0 4.8±0.5 3.0–4.0 3.6±0.3 3.4–5.4 4.6±0.5

Lower lip length 6.4–8.8 7.7±0.6 5.4–7.4 6.3±0.6 6.4–7.8 7.1±0.4

……continued on the next page

SCHMIDT ET AL.

TABLE 3. (Continued)

MORPHOMETRICS Range Mean±%SD Range Mean±%SD Range Mean±%SD

Pectoral-spine length 19.1–24.6 22.4±1.4 12.9–23.1 20.2±2.6 12.6–19.6 17.1±1.8

Pectoral-fin length 19.8–23.0 21.7±0.8 16.5–23.7 21.2±2.0 17.5–21.6 19.3±1.3

Width at pectoral-fin insertion 22.3–25.3 23.5±0.7 22.8–26.2 23.8±0.9 22.4–26.7 23.9±1.0

Length of postcleithral process 9.2–11.3 10.4±0.6 8.8–11.5 9.9±0.9 6.8–9.6 8.4±0.7

Pelvic-fin length 11.5–14.6 12.9±0.8 12.8–16.4 13.9±1.0 11.7–15.3 13.3±0.9

Depth at dorsal-fin insertion 15.8–19.0 17.5±1.0 16.5–23.6 20.4±2.3 16.3–20.9 18.4±1.3

Dorsal-spine length 17.9–23.0 20.3±1.5 13.2–22.2 17.9±2.7 11.6–17.3 13.8±1.5

Dorsal-fin length (longest ray) 17.2–22.4 19.4±1.3 17.1–21.6 19.1±1.3 13.2–18.6 15.8±1.3

Dorsal-fin base length 8.8–10.9 10.1±0.6 9.1–10.3 9.7±0.4 8.0–11.2 9.7±0.8

Dorsal fin to adipose-fin length 14.7–24.0 18.5±2.1 15.6–22.9 19.8±2.3 17.8–25.3 20.1±2.0

Adipose-fin base length 18.9–27.6 22.4±1.9 14.6–23.0 20.2±2.1 16.2–22.8 20.2±1.9

Adipose fin to caudal-ped length 10.7–14.3 12.2±1.0 12.1–16.0 14.1±1.3 10.4–15.4 11.9±1.4

Adipose-fin height 3.1–4.4 3.6±0.3 3.9–5.6 4.6±0.5 3.2–5.6 4.4±0.6

Anal-fin length (longest ray) 12.6–21.3 16.4±3.0 11.8–19.0 15.3±2.1 12.0–20.1 14.8±2.3

Anal-fin base length 9.2–12.4 10.9±1.0 9.1–13.5 11.0±1.1 8.8–13.4 11.3±1.0

Lower caudal-fin lobe length 23.1–27.5 25.2±1.3 23.2–34.0 26.7±2.7 24.4–34.4 28.5±2.3

Upper caudal-fin lobe length 21.8–26.1 23.8±1.2 22.0–29.4 25.3±1.9 22.6–30.6 25.8±1.9

Fork Length 13.4–15.9 14.7±0.7 9.3–16.7 12.6±2.4 10.4–16.2 13.9±1.5

Caudal-peduncle depth (maximum) 9.8–11.6 10.7±0.5 10.8–13.2 12.0±0.7 10.2–13.2 11.7±0.8

Caudal-peduncle length 16.5–19.1 18.0±0.9 16.6–21.2 19.1±1.3 15.6–18.8 16.6±1.2

MERESTICS

Mandibular tooth rows 1,2 1,2 1,2

Mandibular tooth count (total) 12–26 6–16 6–16

Mandibular tooth ct. (functional ant. row) 10–14 1–8 6–8

Mandibular tooth ct.(post.replacement row) 0–12 0–8 0–8

Primary premaxillary teeth (total) 34–58 30–68 44–77

Pectoral-fin count I, 8(22) I, 7(3); I, 8(11); I, 9 (1) I, 7(1); I, 8(19)

Pelvic-fin count i, 6 (22) i, 6 (15) i, 6 (20)

Dorsal-fin count II, 5(2); II, 6(20) II, 4(1); II, 5(14) II, 5(19); II, 6(1)

Anal-fin count iii, 7(13); iii, 8(9) iii, 7(2); iii, 8(11); iii, 9(2) iii, 6(1); iii, 7(7); iii, 8(12)

Caudal-fin count i, 7, 8, i (22) i, 7, 8, i (15) i, 7, 8, i (20)

TWO NEW CHILOGLANIS FROM KENYA

FIGURE 6. Lateral and ventral views of Chiloglanis deckenii (A), TU 203003, Kenya, Coast Province, Lumi River at Taveta

Township: and Chiloglanis brevibarbis (B), NMK FW/2732/1-5, Kenya, Eastern Province, Ragati River at Kwamora area off

Sagana-Karatina Road. Scale bar equals 1 cm. Photographs by R.C. Schmidt.

SCHMIDT ET AL.

Chiloglanis brevibarbis Boulenger 1902

Described from the Tana River basin, Chiloglanis brevibarbis occurs throughout the Athi and Tana River

basins in Central Kenya (Fig. 1). This species in found in a variety of habitat types, although it is usually associated

with or near flowing water. Most commonly utilized habitats are rocks and small boulders in flowing water, this

species is also found near woody debris or exposed roots along the river bank. In the Athi River at Kibwesi, 141

specimens were collected in emergent stands of vegetation in the middle of the sandy channel.

Chiloglanis brevibarbis is the only species of Chiloglanis throughout its range except in the Tsavo River and

potentially in other streams of the middle Athi. In the Tsavo River this species is sympatric with an undescribed

Chiloglanis sp. that is sister to C. deckenii from the Pangani River. Chiloglanis brevibarbis is distinguished from

other Kenyan species in having fewer mandibular teeth, exposed length of mandibular teeth greater than row width,

and in possessing 4–5 rows of well-developed premaxillary teeth in large ovoid tooth pads (Fig. 6). Morphological

variation is observed between Athi and Tana River populations (Fig. 2, also noted in Whitehead 1958) though

biotic dispersal events in the upper reaches of the drainages have likely contributed to admixture between the

populations resulting in incomplete lineage sorting (Schmidt et al. 2014). Little is known of ecology and life

history of this species. Morphometric measurements and meristic counts of C. brevibarbis populations are found in

Table 4.

FIGURE 7. Lateral and ventral views of Chiloglanis somereni, TU 203006, Kenya, Nyanza Province, Riana River, Konyango

area at bridge along Homa Bay-Rongo Road. Scale bar equals 1 cm. Photographs by R.C. Schmidt.

Chiloglanis somereni Whitehead 1958

Chiloglanis somereni, described from the Nyanza Province, occurs in Kenyan rivers and streams that flow into

Lake Victoria (Fig. 1). The species is also found within the Lake Victoria affluents in Tanzania, the Malagarasi

River, and may also occur within western Lake Victoria affluents (Seegers 2008). This species was collected in

large numbers in the Riani River (affluent to the Kuja River) in the swift flowing water over rocks and small

boulders.

TWO NEW CHILOGLANIS FROM KENYA

TABLE 4. Morphometric measurements and meristic counts for Chiloglanis brevibarbis. Standard length expressed in mm. All other measurements expressed in percent SL.

C. brevibarbis Tana R. (N=20)

C. brevibarbis Athi R. (N=15)

C. brevibarbis Tsavo R. (N=22)

MORPHOMETRICS

Range

Mean±%SD

Range

Mean±%SD

Range

Mean±%SD

Standard length (mm)

35.1-61.8

31.9-49.0

34.1-57.3

Head length

29.7-34.3

32.0±1.4

26.6-33.4

30.1±1.8

27.5-33.2

31.1±1.5

Head depth (maximum)

14.2-18.7

16.1±1.3

12.3-17.4

14.6±1.4

14.8-18.6

16.0±0.9

Body depth at anus

12.6-15.6

14.1±0.8

9.5-14.1

12.4±1.2

14.2-18.4

15.5±0.9

Occipital shield width (minimum)

3.2-4.4

3.9±0.3

3.3-4.1

3.8±0.2

3.3-4.2

3.8±0.3

Prepectoral length

28.4-35.4

31.4±1.4

28.0-32.1

30.4±1.1

28.1-31.6

30.1±1.1

Predorsal length

40.0-43.4

41.7±1.0

37.5-42.0

39.8±1.3

40.0-43.3

31.3±1.0

Prepelvic length

56.8-62.1

59.7±1.4

56.4-61.8

58.3±1.5

55.3-62.3

58.2±1.8

Preanal length

67.0-74.6

71.2-2.0

69.8-75.9

72.0±1.9

69.0-75.0

71.9±1.7

Eye diameter (horizontal)

3.9-5.2

4.6±0.3

4.2-5.3

4.7±0.3

4.0-5.1

4.5±0.3

Orbital interspace

6.3-7.9

7.3±0.5

6.3-7.5

6.8-0.3

5.6-7.8

7.0±0.6

Snout length

19.0-23.4

20.7±1.2

17.3-21.5

19.1±1.1

18.3-21.5

19.9±0.8

Premaxillary tooth-patch width

11.3-16.0

13.1±1.4

10.1-13.2

11.8±0.8

10.6-16.7

12.4±1.2

Premaxillary tooth-patch length

2.4-3.3

3.0±0.2

2.6-3.4

2.9±0.3

2.9-4.0

3.2±0.3

Mandibular tooth row width

1.5-2.9

2.0±0.4

1.6-2.4

2.0±0.3

1.4-2.4

1.9±0.3

Anterior nares interspace

3.9-5.1

4.5±0.4

3.5-4.9

4.3±0.4

3.8-5.8

4.6±0.4

Posterior nares interspace

3.9-5.3

4.4±0.4

3.5-5.0

4.3±0.4

3.9-5.1

4.6±0.3

Maxillary barbel length

6.3-7.9

7.0±0.4

7.5-10.3

8.6±0.8

7.1-9.9

8.3±0.7

Medial mandibular barbel length

0.7-3.0

2.1±0.5

2.0-3.1

2.5±0.3

1.8-3.3

2.4±0.4

Lateral mandibular barbel length

1.6-4.0

3.4±0.6

3.3-4.4

3.8±0.4

3.3-5.0

4.0±0.4

Mouth width

8.0-10.3

9.1±0.5

7.3-8.9

8.2±0.4

7.0-10.1

8.3±0.7

Oral disc width

17.6-21.9

19.6±1.2

16.2-19.7

17.5±1.0

17.7-22.4

19.5±1.2

Oral disc length

16.5-21.2

18.7±1.2

15.8-18.9

17.4±0.9

17.3-21.8

19.2±1.2

Upper lip length

3.8-5.4

4.4±0.4

3.5-5.0

4.1±0.5

4.0-5.8

4.7±0.5

Lower lip length

6.3-8.2

7.3±0.5

5.6-7.1

6.5±0.5

6.3-8.0

7.2±0.4

….continued on the next page

SCHMIDT ET AL.

TABLE 4. (continued)

MORPHOMETRICS

Range

Mean±%SD

Range

Mean±%SD

Range

Mean±%SD

Pectoral-spine length

18.6-24.6

21.3±1.6

17.0-21.9

19.5±1.3

13.9-20.7

17.5±1.7

Pectoral-fin length

20.1-24.2

22.5±1.2

18.7-22.8

20.6±1.4

17.9-23.1

19.4±1.2

Width at pectoral-fin insertion

23.9-26.9

25.4±0.9

21.5-25.6

23.8±1.1

22.2-26.1

24.0±1.1

Length of postcleithral process

8.3-10.6

9.4±0.7

7.0-9.5

8.4±0.7

7.6-12.4

9.0±1.0

Pelvic-fin length

11.9-14.9

13.0±0.8

11.1-13.9

12.3±0.8

11.2-15.1

12.9±0.9

Depth at dorsal-fin insertion

14.9-20.1

17.4±1.6

12.6-18.6

15.3±1.6

15.5-22.1

18.2±1.7

Dorsal-spine length

13.7-21.3

16.5±2.0

12.2-16.7

14.7±1.1

11.4-20.2

14.4±2.0

Dorsal-fin length (longest ray)

15.3-20.4

17.3±1.4

15.2-18.6

16.8±0.9

13.9-19.5

16.3±1.5

Dorsal-fin base length

8.4-12.0

9.9±1.0

7.2-11.9

9.6±1.0

8.4-11.1

9.5±0.7

Dorsal fin to adipose-fin length

17.9-25.4

21.5±2.0

16.9-23.8

20.9±2.2

15.5-26.0

20.9±2.6

Adipose-fin base length

13.7-18.5

16.3±1.4

15.0-23.0

18.3±2.0

15.9-22.5

19.9±1.9

Adipose fin to caudal-ped length

9.9-14.1

11.7±1.2

10.1-13.6

12.2±1.0

9.6-14.2

11.5±1.0

Adipose-fin height

2.8-4.2

3.6±0.4

3.7-4.9

4.3±0.4

3.6-5.1

4.3±0.4

Anal-fin length (longest ray)

11.8-17.4

14.9±1.7

11.7-17.9

13.8±1.7

12.5-17.3

14.6±1.3

Anal-fin base length

7.5-12.6

11.0±1.3

9.4-12.8

11.0±1.0

9.7-13.2

11.7±1.0

Lower caudal-fin lobe length

26.8-33.7

30.1±1.8

27.2-33.1

30.4±1.8

27.2-32.1

29.2±1.5

Upper caudal-fin lobe length

25.8-31.3

28.1±1.6

24.3-29.8

27.9±1.7

23.8-30.6

26.7±1.6

Fork Length

11.8-15.3

13.6±1.0

12.5-16.7

14.4±1.1

12.4-17.0

14.5±1.2

Caudal-peduncle depth (maximum)

8.9-11.7

10.1±0.7

10.1-11.8

11.0±0.6

10.2-12.6

11.5±0.6

Caudal-peduncle length

13.6-18.5

15.4±1.3

14.1-18.1

15.9±0.3

14.8-18.4

16.0±1.0

Meristics

Mandibular tooth rows

1,2

Mandibular tooth count (total)

6-15

6-16

7-18

Mandibular tooth count (functional anterior row)

5-8

6-8

6-9

Mandibular tooth count (post. replacement row)

0-9

0-8

0-9

Primary premaxillary teeth (total)

51-75

55-90

44-112

Pectoral-fin count

I, 7(2); I, 8(17) I, 9(1)

I, 7(2); I, 8(13)

I, 7(2); I, 8(20)

Pelvic-fin count

i,6 (20)

i, 6 (15)

i, 6 (22)

Dorsal-fin count

II, 5(19); II, 6(1)

II, 4(2); II, 5(13)

II, 5 (22)

Anal-fin count

iii, 7(12); iii, 8(9); iii, 9(1)

iii, 7(10); iii, 8(5)

iii, 7(4); iii, 8(12); iii, 9(5)

Caudal-fin count

i, 7, 8, i (20)

i, 7, 8, i (15)

i, 7, 8, i (22)

TWO NEW CHILOGLANIS FROM KENYA

Chiloglanis somereni is allopatrically distributed and readily distinguished from other Kenyan suckermouth

catfishes. It is a sexually dimorphic species, with males displaying elongated rays in the anal fin (Fig. 7). This

species has more mandibular teeth (10–12 in functional row) than all other Kenyan species except C. devosi and

has longer pectoral and dorsal spines than C. devosi. It is one of the larger suckermouth catfishes found in Kenya

with a maximum reported size of 68 mm SL. Whitehead (1958) provided a few comments on reproductive biology,

but little else is known of the ecology and life history of C. somereni. Morphometric measurements and meristic

counts of Kenyan C. somereni are found in Table 3.

Additional material examined

Chiloglanis brevibarbis: TU 203004, 20 ALC, 31.8–49.0 mm SL; Kenya, Eastern Province, Athi River at

Kibwezi—Kitui Road bridge, 02.20419° S, 38.05883° E; 2012 IRES team, 20 June 2012.—CUMV 98651, 10

ALC, 34.2–45.3 mm SL; collection data same as TU 203004. NMK FW/2732/1-5, 5 ALC, 50.3–61.8 mm SL;

Kenya, Eastern Province, Ragati River at Kwamora area off Sagana-Karatina Road, 00.58778° S, 37.19130° E;

2012 IRES team, 15 June 2012.—TU 202993, 22 ALC, 35.1–45.9 mm SL; Kenya, Eastern Province, Murera River

outside Meru National Park, 00.27413° N, 38.12201° E; 2012 IRES team, 13 June 2012.—TU 203005, 9 ALC,

33.1–47.8 mm SL; Kenya, Coast Province, Tsavo River at Mombasa Road Bridge, 02.99466° S, 38.46074° E; 2012

IRES team, 20 June 2012.—NMK FW/2756/1-20, 11 ALC, 33.2–57.3 mm SL; tissue voucher: IRES 10184;

collection data same as TU 203005.—NMK FW/559/1, 1 ALC, 40.9 mm SL; Kenya, Coast Province, Tsavo River

at Ziwani gate.—BMNH 1902.5.26.19, photograph of ALC holotype, Kenya, Mathioya River.—Chiloglanis

deckenii: TU 203003, 20 ALC, 28.0–62.2 mm SL; Kenya, Coast Province, Lumi River at Taveta Township,

03.38950° S, 37.70597° E; 2012 IRES team, 19 June 2012.— ZMB 16387, photographs of 16 ALC syntypes,

Tanzania, Africa orientalis.—Chiloglanis somereni: TU 203006, 20 ALC, 42.6–68.0 mm SL; Kenya, Nyanza

Province, Riana River, Konyango area at bridge along Homa Bay-Rongo Road 00.70492° S, 34.84426° E; 2011

IRES team, 30 June 2011.—CUMV 98650, 5 ALC, 42.8–60.8 mm SL; collection data same as TU 203006.—

NMK FW/527/1-7, 7 ALC, 44.7–52.0 mm SL; Kenya, Nyanza Province, Runyerere River (affluent to Yala

River).—BMNH 1958.7.18.1, photograph of ALC holotype, Kenya, Nyanza Province, Waroya River.—

Chiloglanis sp. aff. deckenii: NMK FW/558/1, 1 ALC, 44.0 mm SL; Kenya, Coast Province, Tsavo River at

Ziwani gate.—TU 204097, 11 ALC, 35.9–46.2 mm SL; Kenya, Coast Province, Tsavo River at Mombasa Road

Bridge, 02.99466° S, 38.46074° E; 2012 IRES team, 20 June 2012.—NMK FW/3960/1-9, 9 ALC, 33.1–47.8 mm

SL; collection data same as TU Cat 203005.

Acknowledgements

Funding was provided by NSF OISE: 0968727; 1215395. The following participants of the IRES program whose

dedication and hard work allowed the project to succeed. Collecting team members denoted by superscript (2010

2011

, and 2012

) Principal investigators: D. Sigana

ABC

(University of Nairobi), M. Ogada

ABC

(Conservation

Solutions Afrika), and G. Talarchek (Tulane University). IRES student participants: R. Anderson

, D. Lach

, L.

Mathews

, N. Moses

, H. Strobel

, and T. Woods

(Tulane University); S. Abade

, J. Abong’o

, L. Asande

, K.

Laban Losili

, C. Mburu

, P. N’gang’a

, M. Odhiambo

, R. Onwong’a

, W. Owako

, M. Oyier

, P. Tanui

(University of Nairobi); A. Ewing

, M. Patterson

, and L. Spivey

(Xavier University of New Orleans); and J.

Gathua

ABC

, G. Kosgei

, T. Ndiwa

(Kenya Wetlands Biodiversity Research Group). In addition we thank the

Kenyan Wildlife Service (KWS) particularly J. Nyunja (Wetlands program) and the Warden and staff at Meru

National Park for allowing us to collect within the park boundaries. We thank the Mpala Research Center and its

staff for their hospitality. Peter Nyamenya (Kisumu Museum) and Dr. W. Ojwang (KEMFRI) were of great

assistance in Nyanza County. Our drivers A. Mukiri and L. Nzangi Kioko (NMK), A. Mureithi and I. Mogoi (UoN)

provided wonderful service. We would also like to thank K. Githui and A. Mwaura (NMK), F. Nyaga and J. Samoei

(UoN) for their assistance in their respective laboratories. The staff of the NMK Ichthyology and Herpetology

sections provided invaluable support while in the field and in the laboratory. J.G. Mann (TU) assisted with

packaging and shipping material. M.H. Doosey and reviewers provided feedback that improved the manuscript.

SCHMIDT ET AL.

Literature cited

Friel J.P. & Vigliotta, T.R. (2011) Three new species of African suckermouth catfishes, genus Chiloglanis (Siluriformes:

Mochokidae), from the lower Malagarasi and Luiche rivers of western Tanzania. Zootaxa, 3063, 1–21.

Riehl, R. & Baensch, A. (1990) Mergus Aquarien Atlas. Band 3. Melle, Germany, Mergus, 1104 pp.

Sabaj Pérez, M.H. (2010) Standard symbolic codes for institutional resource collections in herpetology and ichthyology: an

Online Reference. Version 2.0. American Society of Ichthyologists and Herpetologists, Washington, DC. Available from:

http://www.asih.org/ (accessed 20 May 2015)

Seegers, L. (2008) The Catfishes of Africa: A Handbook for Identification and Maintenance. Aqualog Verlag, Rodgau,

Germany, 604 pp.

Seegers, L., De Vos, L. & Okeyo, D.O. (2003) Annotated checklist of the freshwater fishes of Kenya (excluding the lacustrine

haplochromines from Lake Victoria). Journal of East African Natural History, 92, 1, 11–47.

http://dx.doi.org/10.2982/0012-8317(2003)92[11:ACOTFF]2.0.CO;2

Schmidt, R.C., Bart, H.L., Nyingi, D.W. & Gichuki, N.N. (2014) Phylogeny of suckermouth catfishes (Mochokidae:

Chiloglanis) from Kenya: The utility of Growth Hormone introns in species level phylogenies. Molecular Phylogenetics

and Evolution, 79, 415–421.

http://dx.doi.org/10.1016/j.ympev.2014.07.011

Skelton P.H. & White, P.N. (1990) Two new species of Synodontis (Pisces: Siluroidei: Mochokidae) from southern Africa.

Ichthyological Exploration of Freshwaters, 1, 277–287.

Vigliotta, T.R. (2008) A phylogenetic study of the African catfish family Mochokidae (Osteichthyes, Ostariophysi,

Siluriformes), with a key to genera. Proceeding of the Academy of Natural Science of Philadelphia, 157,1, 73–136.

http://dx.doi.org/10.1635/0097-3157(2008)157[73:APSOTA]2.0.CO;2

Whitehead, P.J. (1958) A new species of Chiloglanis (Pisces, Mochocidae) in Kenya. Journal of Natural History, 1, 3, 197–

208.

http://dx.doi.org/10.1080/00222935808650938

Kenyan Chiloglanis Morphometrics

Data

February 2016

Ray C. Schmidt · Henry Bart · Wanja Dorothy Nyingi

Download

An integrative taxonomic review of the Natal mountain catfish, Amphilius natalensis Boulenger 1917 (Siluriformes, Amphiliidae), with description of four new species

Article

Full-text available

Apr 2021
J FISH BIOL

An integrative taxonomic analysis combining mitochondrial cytochrome oxidase subunit I sequences, morphology, colour pattern and two species delimitation approaches revealed the existence of five lineages within the Natal mountain catfish, Amphilius natalensis, in southern Africa. These lineages are separated by substantial genetic divergences (1.6%–9.46%), and they can be consistently distinguished from one another based on a combination of morphology and colour pattern differences. Additionally, the lineages are allopatrically distributed and confined to isolated river systems draining discrete mountain ranges, which makes gene flow among them unlikely. One of these lineages is A. natalensis s.s., which is confined to the uMngeni and Tukela river systems in KwaZulu Natal (KZN) Province in South Africa. The other four lineages represent new species to science which are described as Amphilius zuluorum sp. nov., endemic to the uMkhomazi River system in KZN, Amphilius engelbrechti sp. nov., endemic to the Inkomati River system in Mpumalanga Province in South Africa, Amphilius marshalli sp. nov., endemic to the Pungwe and Lower Zambezi river systems in Zimbabwe and Mozambique, and Amphilius leopardus sp. nov., endemic to the Ruo River in Malawi. The results show that Amphilius laticaudatus which is endemic to the Buzi River system in Zimbabwe and Mozambique, belongs to the A. natalensis s.l. complex. A redescription of A. laticaudatus is presented and an updated identification key for the mountain catfishes of southern Africa is provided.

Hidden in the riffles: A new suckermouth catfish (Mochokidae, Chiloglanis) from the middle Zambezi River system, Zimbabwe

Article

Full-text available

Apr 2024

The recent surge in the discovery of hidden diversity within rheophilic taxa, particularly in West and East Africa, prompted a closer examination of the extent to which the current taxonomy may obscure the diversity of riffle-dwelling suckermouth catfishes in the genus Chiloglanis in southern Africa. Currently, the region comprises eight valid species within this genus. Seven of them have relatively narrow geographic distribution ranges except for C. neumanni, which is considered to be widely distributed, occurring from the Buzi River system in the south, and its northern limit being the eastward draining river systems in Tanzania. Recent surveys of the middle Zambezi River system revealed Chiloglanis specimens that were distinguishable from the known species of the genus from southern Africa. Integration of molecular and morphological data indicated that these specimens from the Mukwadzi River represent a new species to science, herein described as Chiloglanis carnatus Mutizwa, Bragança & Chakona, sp. nov. This species is readily distinguished from its southern African congeners by the possession of a distinctive extended dermal tissue covering the base of the dorsal fin and the possession of ten mandibular teeth (vs 8, 12, or 14 in the other taxa). Results from this study add to the growing evidence of a high level of undocumented diversity within riffle-dwelling taxa in southern Africa.

Species of the cyprinid genus Garra in Mount Kenya, East Africa: Species delineation, taxonomy and historical biogeography

Article

Full-text available

Jul 2023

The cyprinid genus Garra is so far represented in Mount Kenya streams by a single species, but which species it should be referred to as remains yet to be determined. Molecular phylogenetic analysis of Garra species from the mountain is still lacking. Here, an integrative analysis, based on morphological and molecular data, unravelled the hidden species diversity of Garra from Mount Kenya. In mitochondrial genes‐based trees, samples formerly identified as Garra dembeensis from the mountain nested into three distinct lineages that were distantly allied to the lineage constituted by topotypical samples of the species; the three lineages are morphologically distinguishable, and thus represent three distinct species: Garra hindii and two undescribed species, herein named as Garra alticauda sp. nov. and Garra minibarbata sp. nov., respectively, from the Mara River and the Ragati River of the mid‐upper Tana River basin. The phylogeographic pattern of the three species is incongruent with the present‐day basin pattern of Mount Kenya. The allopatry of the paired species G. alticauda and G. hindii points to river piracy ever incurring between the upper Ewaso Ngiro River and the middle Tana River basin in Mount Kenya. Besides, the molecular phylogenetic analysis of sampled African Garra species in this study, based on a broad set of sequences, provides evidence in support for the existing hypothesis of Asia‐to‐Africa biodispersal via the Arabian Peninsula to the Horn of Africa.

The current status of Barbus species in Lake Victoria Basin, Kenya: A review

Article

Full-text available

Sep 2022

Emily Jepyegon Chemoiwa

Lake Victoria is known for its rich fish biodiversity having been home to over 500 fish species. However, over 200 species have become extinct and as a result, it is classified as a world hotspot of species loss. Some of the examples of endemic species that disappeared from the lake and are endangered include the Haplochromines and the Barbus species. The Barbus species is currently not seen in the fish landings from Lake Victoria. It is deemed to have sought refuge in the riverine ecosystems, dams and the adjacent satellite lakes within the Lake Victoria Basin. This has resulted in several gaps emerging including its current status as its taxonomical identification still remains a puzzle to many scientists. This paper, therefore, tries to unearth the foregoing by reviewing the already available literature with an emphasis on the LVB Kenyan part. The Labeobarbus altianalis is still named Barbus altianalis even in the most recent publications thus complicating further. In its distribution, the Barbus species does not occur in the lake currently but is a common candidate in the rivers, dams and satellite lakes within the basin. Some of the cited reasons for its disappearance: are predation by Lates niloticus, overfishing, competition from exotic species, pollution and climate change. However, different studies try to pinpoint its presence in some rivers and this according to an observation made in this study is due to biased sampling, which excludes some rivers in the basin. It is concluded that the taxonomic identification of Barbus species in LVB Kenya remains elusive and this has been blamed on skewed sampling with little regard to all ecosystems in the basin. The paper recommends that an elaborate simultaneous study be done in all the rivers within the LVB, Kenya to collect reliable data for use in Barbus species taxonomy and general biology. Further, county governments in the basin should develop sound policy frameworks on how to sustainably manage riverine fisheries including the domestication of the species in aquaculture.

Food web dynamics

Chapter

Full-text available

Nov 2024

Knowledge of the trophic structure and the major energy sources supporting metazoan production are important considerations for biodiversity conservation and ecosystem management. African streams and rivers face multiple stressors from agricultural intensification, deforestation, and municipal and industrial effluents coupled with uncontrolled water abstractions. Yet, the effects of these influences on ecosystem structure and functioning are poorly understood. In this chapter, we review the trophic dynamics of African riverine ecosystems with a focus on trophic structure, the major sources of energy supporting food webs, and the influence of human activities. While much of the data used for this review are from African studies, we also reference other studies in the tropics for comparison and to fill existing knowledge gaps. Based on available information, autochthony, short food chains, and an increased tendency toward omnivory characterize food webs in African streams and rivers. However, trophic interactions and dynamics in these systems are witnessing changes caused by human activities. Changes in trophic diversity and dynamics include shifts from allochthony to autochthony following the deforestation of forested headwater streams, top-down control of local fish and invertebrate populations caused by introduced predatory fish such as trout, and shrinkage of trophic niche sizes caused by land use change. Despite these developments, studies on food web structure and trophic dynamics are very limited in low-order streams, and we have identified future research needs that need to be addressed to fill knowledge gaps that would hinder biodiversity conservation and effective management of riverine ecosystems in African rivers, including their fisheries.

Trophic niche patterns of endangered Sandelia bainsii and Amatolacypris trevelyani in the Eastern Cape, South Africa: Insights from stable isotope analysis

Article

Feb 2024

Despite supporting a disproportionately large fraction of the global biodiversity, freshwater ecosystems are ranked as the most highly threatened habitats ahead of both terrestrial and marine ecosystems. Furthermore, many regions are still characterized by limited knowledge on taxonomy and ecology of freshwater fishes. The need for ecological information in understudied regions is important particularly where there are recent discoveries of new species and unique lineages and for threatened and endangered taxa that require conservation management. This study evaluated the trophic ecology of two freshwater fish species Sandelia bainsii and Amatolacypris trevelyani that are both classified as endangered in the International Union for Conservation of Nature (IUCN) Red List. These two species, which are narrow‐range endemics in the Eastern Cape, South Africa, comprise allopatric lineages whose ecology is poorly known. This study used stable isotope analysis to evaluate the food web patterns, explore the trophic niche dynamics and estimate the prey source contributions for the two species in different headwater habitats. The fishes isotopic niche sizes were spatially variable, suggesting the likely importance of stochastic variation in resource availability and probable interspecific interactions. The three lineages within S. bainsii exhibited low isotopic niche overlap onto those of sympatric fishes in most habitats. Isotopic mixing model revealed that these lineages' diets were mostly dominated by gatherers/collectors. In comparison, the two lineages within A. trevelyani exhibited high niche overlap with other species and generally had variable diets. Despite the low and high niche overlap patterns of S. bainsii and A. trevelyani , respectively, the isotopic niche overlap patterns of co‐occurring species onto those of the former suggest the likely lack of competitive hierarchies. The trophic niche patterns of these two endangered species helped to shed some light on the potential invasion risks by non‐piscivorous fishes with opportunistic feeding habits, which could exert competitive interspecific interactions.

Two New Species of Suckermouth Catfishes (Mochokidae: Chiloglanis) from Upper Guinean Forest Streams in West Africa

Article

Full-text available

Jul 2023

Drivers of species richness and beta diversity of fishes in an Afrotropical intermittent river system

Article

Full-text available

Dec 2022

Tropical freshwater ecosystems are some of the most threatened systems yet remain understudied relative to temperate systems. Here, we look at the drivers of community structure of fishes in a tropical and intermittent system in central Kenya. We conducted monthly samples within the upper Northern Ewaso Ng'iro to assess variation in community composition and abiotic characteristics. We analyzed species richness along the longitudinal gradient, computed beta diversity within the system, relative contributions of each site, and partitioned beta diversity metrics into nestedness and turnover components. We found that, similar to temperate intermittent systems, species richness varied along the longitudinal gradient, nestedness contributions to beta diversity exceeded those of turnover, and environmental and spatial variables determined patterns of beta diversity. Sites at the highest and lowest ends of the species richness gradient showed the highest contributions to beta diversity, suggesting sites important for preservation or restoration initiatives, respectively. With ongoing water extraction and conflict over resources throughout the region, this study highlights the need for further investigations of the effects of multiple stressors on biodiversity patterns and ecosystem functioning in tropical stream communities. Here, we look at the beta diversity and drivers of species richness in fishes in the upper Northern Ewaso Ng'iro River in Kenya. We found nestedness contributions to beta diversity exceeded those of turnover. Sites at the highest and lowest ends of the species richness gradient showed the highest contributions to beta diversity, suggesting sites important for preservation or restoration initiatives, respectively.

ENVIRONMENT, BIODIVERSITY AND HEALTH IN MOZAMBIQUE DNA barcoding to assess species identification in museum samples of Amphiliidae and natural samples of Cichlidae from Southern Mozambique

Article

Full-text available

Sep 2022

The biodiversity protection and monitorning is one of main goals of natural history musems worldwide. Conservation issues are particularly important for freshwater fish which are one of the most threatened taxa for the consequences of climate change and human activies. In Mozambique freshwater rivers are poorly explored and the impact of aquaculture and human activities on local biodiversity in almost unknown. Here we propose the barcoding analysis of cytochrome c oxidase I (COI) mitochrondrial DNA of 41 frehswater fishes catched in four rivers of southern Mozambique and 53 from a museum collection. As evidence of previous knowledge gaps, barcoding results revealed twenty new haplotypes described for the first time in the taxa Cichlidae and Amphilidae. From a methodological point of view, the barcoding approach demonstrated a critical point connected to the requested 650 bp length of amplified sequences. In fact, high weight genomic DNA is unattainable from museum samples and also in wildlife samples collected in pristine rivers. For this reason we furtherly tested the efficiency of DNA mini-barcoding analysis for 53 fish from a museum collection. The Mini-barcode method retrieved 56.6% of sequences successfully analyzed versus 3% of barcoding. The high performance of this thecniques is discussed in relation to biodiversity monitoring and to fill the taxonomy gaps in museum collections.

Ichthyological Exploration of Freshwaters An international journal for field-orientated ichthyology Chiloglanis msirii, a new species of African suckermouth catfish (Teleostei: Mochokidae), from the Upper Congo basin

Article

Full-text available

Nov 2021
ICHTHYOL EXPLOR FRES

A detailed examination of recently collected specimens of Chiloglanis from the Fungwe and Mwanza rivers and those collected during previous surveys of the Lukuga basin revealed the existence of a new species of African suckermouth catfish in the Upper Congo basin. The new species, herein described as Chiloglanis msirii, is readily distinguished from its congeners in the Congo basin by: the lack of a mid-ventral cleft on the oral disc; the possession of a single row of widely spaced mandibular teeth; and the possession of a forked caudal fin. Outside the Congo basin, the new species closely resembles C. swierstrai from which it is however readily distinguished by having a lower number of total vertebrae and a thicker caudal peduncle. Based on the examined specimens, there was no apparent evidence of sexual dimorphism in shape and size of the fins, body ornamentation, or tuber-culation of the skin. This description increases the number of known species of suckermouth catfishes in the Upemba National Park (UNP) to four (C. lufirae, C. microps, C. pojeri and C. msirii). Further surveys and the use of integrative taxonomic approaches will likely uncover additional undocumented species diversity in this park. There are concerns, however, that some of this diversity might be lost even before it is formally documented, because of the excessive use of ichthyotoxins and the construction of impoundments that cause drowning of the riffles which are critical habitats for rheophilic species, particularly those in the genus Chiloglanis and other specialised groups. The present study highlights and discusses the challenges associated with fish protection in the UNP, with emphasis on the Fungwe and Mwanza rivers.

Three new species of African suckermouth catfishes, genus Chiloglanis (Siluriformes: Mochokidae), from the lower Malagarasi and Luiche rivers of western Tanzania

Article

Full-text available

Oct 2011
ZOOTAXA

Recent fieldwork and review of existing collections containing Chiloglanis specimens from the lower Malagarasi and Luiche rivers in western Tanzania has revealed three new species that are readily distinguished from described congeners by external features. Two of the species, Chiloglanis igamba sp. nov., and Chiloglanis orthodontus sp. nov. are restricted to the Malagarasi basin. The third species, Chiloglanis kazumbei sp. nov., is more broadly distributed in both the Malagarasi and adjacent Luiche basin. A key to all described species within these two basins is presented, along with comments on the distribution and validity of nominal Chiloglanis species examined during this study.

Phylogeny of suckermouth catfishes (Mochokidae: Chiloglanis) from Kenya: The utility of Growth Hormone introns in species level phylogenies

Article

Jul 2014

African suckermouth catfishes (Mochokidae: Chiloglanis) occur in freshwater throughout tropical Africa. Specimens from all major drainages across Kenya were collected over three field seasons. Here we present a phylogeny inferred from both mitochondrial cytochrome b (cyt b) and introns of the nuclear growth hormone gene (GH). The phylogeny inferred from introns is largely congruent with the results from an analysis of cyt b. The length and variability of GH introns make them ideal species level nuclear markers without the problem of introgression commonly encountered with mitochondrial genes. This analysis confirmed the presence of two previously known undescribed Chiloglanis species and also suggests the presence of previously unknown diversity within the Athi River system. The resulting phylogeny also indicates the presence of two separate lineages within C. brevibarbis. The historical biogeography of Chiloglanis within Kenya is discussed. The utility of GH intron for species level phylogenies of Siluriformes is compared to that in other groups.

A new species of Chiloglanis (Pisces, Mochocidae) in Kenya

Article

Mar 1958

Peter J. Whitehead

A phylogenetic study of the African catfish family Mochokidae (Osteichthyes, Ostariophysi, Siluriformes), with a key to genera

Article

Jan 2009

Thomas R. Vigliotta

A hypothesis of phylogenetic relationships is presented for the African catfish family Mochokidae based on a maximum parsimony analysis of 93 morphological characters in 41 ingroup and 19 outgroup taxa. The analysis reveals that the Mochokidae are a monophyletic group and that Mochokus Joannis (1835), Mochokiella Howes (1980), Acanthocleithron Nichols and Griscom (1917) and Microsynodontis Boulenger (1903) are monophyletic and valid as distinct genera within the family. Synodontis Cuvier (1816) must include Hemisynodontis membranacea and Brachysynodontis batensoda to be monophyletic, which are reassigned to Synodontis herein. Chiloglanis Peters (1868) is rendered paraphyletic by nested placement of Atopochilus Sauvage (1879), Euchilichthys Boulenger (1900) and Atopodontus Friel and Vigliotta (2008), a new genus described separately in this volume. Euchilichthys is rendered paraphyletic by nested placement of Atopochilus savorgnani. The monophyly of Atopochilus could not be tested because only one species was available for study. Atopodontus is monophyletic and valid as a distinct genus. Well-supported suprageneric clades within the family include a new tribe, the Atopochilini, with Atopodontus as the sister group to a clade composed of Atopochilus and Euchilichthys. A clade composed of all suckermouthed species, the redefined subfamily Chiloglanidinae, includes tribe Atopochilini nested within Chiloglanis. Taxonomic issues related to paraphyly of Chiloglanis and Euchilichthys require further research on a greater number of taxa before being addressed. Subfamily Chiloglanidinae forms a polytomy with Synodontis and Microsynodontis. Acanthocleithron, followed by Mochokiella and then Mochokus are recovered as consecutive sister groups to that polytomy. A list of synapomorphies is provided for each major clade recovered, but most clades are left unnamed at this point. A number of the well-supported clades are characterized by changes in the oral jaws and mouth, apparently a key theme in mochokid evolution. Finally, the analysis suggests that the sister group of the Mochokidae is a clade composed of the South American Doradidae plus Auchenipteridae, though support for the relationship is low. Synapomorphies supporting the recovered sister group relationship and possible synapomorphies supporting alternative sister group relationships to the Malapteruridae and Amphiliidae are provided. New taxon: Atopochilini Vigliotta

Annotated Checklist of the Freshwater Fishes of Kenya (excluding the lacustrine haplochromines from Lake Victoria)

Article

Jan 2009
J East Af Nat Hist Soc Natl Mus

A checklist of the freshwater fishes of Kenya is presented. Pending more accurate information on their status, the lacustrine Lake Victoria haplochromines have been omitted from the list. Currently 206 species belonging to 38 families are known from Kenyan fresh waters. With at least 50 species, Cyprinidae are by far the largest fish family in the country followed by Cichlidae, Mochokidae, Mormyridae and Characidae, respectively represented by 28, 15, 15 and 12 species. At least 18 fish species were introduced, deliberately or after escaping from fish farms or breeding stations. The list includes the distribution of each species in Kenya, common English names and local names in various African indigenous languages as well as annotations referring to introductions, distribution, taxonomic status of the species and older records from literature.

Jan 2010

R Anderson
D Lach

Acknowledgements Funding was provided by NSF OISE: 0968727; 1215395. The following participants of the IRES program whose dedication and hard work allowed the project to succeed. Collecting team members denoted by superscript (2010 A, 2011 B, and 2012 C ) Principal investigators: D. Sigana ABC (University of Nairobi), M. Ogada ABC (Conservation Solutions Afrika), and G. Talarchek (Tulane University). IRES student participants: R. Anderson C, D. Lach B, L.

Mergus Aquarien Atlas

Jan 1990
1104

R Riehl
A Baensch

Riehl, R. & Baensch, A. (1990) Mergus Aquarien Atlas. Band 3. Melle, Germany, Mergus, 1104 pp.

Standard symbolic codes for institutional resource collections in herpetology and ichthyology: an Online Reference. Version 2.0

May 2010

M H Sabaj Pérez

Sabaj Pérez, M.H. (2010) Standard symbolic codes for institutional resource collections in herpetology and ichthyology: an Online Reference. Version 2.0. American Society of Ichthyologists and Herpetologists, Washington, DC. Available from: http://www.asih.org/ (accessed 20 May 2015)

The Catfishes of Africa: A Handbook for Identification and Maintenance

Jan 2008
pp

L Seegers

Seegers, L. (2008) The Catfishes of Africa: A Handbook for Identification and Maintenance. Aqualog Verlag, Rodgau, Germany, 604 pp.

Two new species of Synodontis (Pisces: Siluroidei: Mochokidae) from southern Africa

Jan 1990
ICHTHYOL EXPLOR FRES
277-287

P H Skelton
P N White

Skelton P.H. & White, P.N. (1990) Two new species of Synodontis (Pisces: Siluroidei: Mochokidae) from southern Africa. Ichthyological Exploration of Freshwaters, 1, 277-287.

Two new species of African suckermouth catfishes, genus Chiloglanis (Siluriformes: Mochokidae), from Kenya with remarks on other taxa from the area

Abstract and Figures

Supplementary resource (1)

Recommended publications

The Teryacette Problem

Sediment Transport in the Lower Guadalupe and San Antonio Rivers

Distribution of non-native suckermouth armoured catfish Pterygoplichthys ambrosettii in the upper Pa...

Distribution and habitat use of Caribou, Rangifer tarandus caribou, and Moose, Alces alces andersoni...