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A New Genus and Species of Hypoptopomatine Catfish (Siluriformes:
Loricariidae) from the Upper Rio São Francisco Basin, Brazil
Author(s) :Roberto E. Reis, Edson H. L. Pereira, and Pablo Lehmann A.
Source: Copeia, 2012(1):6-11. 2012.
Published By: The American Society of Ichthyologists and Herpetologists
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A New Genus and Species of Hypoptopomatine Catfish
(Siluriformes: Loricariidae) from the Upper Rio Sa˜o Francisco Basin, Brazil
Roberto E. Reis
, Edson H. L. Pereira
, and Pablo Lehmann A.
Plesioptopoma curvidens is a new genus and species of hypoptopomatine loricariid from the upper Rio Paraopeba, a
tributary to the Rio Sa˜o Francisco in southeastern Brazil. Plesioptopoma is attributed to the hypoptopomatines based on
five shared synapomorphies, and differs from all remaining members of the subfamily by having the premaxilla and
dentary tooth series strongly curved mesially, in such a way that the mesial portion of the tooth series in both sides are
turned and run parallel to each other, the caudal peduncle distinctly quadrangular in cross-section, and the anterior
margin of the snout devoid of dermal plates.
KNOWLEDGE about the diversity among the Neo-
tropical cascudinhos of the subfamily Hypoptopo-
matinae is increasing at a fast rate in the last two
decades, with eight of the 19 genera currently known having
been described in this period. Despite the intense ongoing
effort toward uncovering the hidden diversity of hypopto-
pomatines, new taxa not referable to any of the known
genera are still being discovered by fish taxonomists in
intensively sampled areas such as the upper Rio Sa˜o
The fish described herein is unambiguously identified as
a member of the Hypoptopomatinae, despite sharing some
features with the Neoplecostominae, based on its peculiar
morphology and anatomy, being at the same time readily
distinguishable from all other members of the subfamily.
Below we diagnose the new taxon describing a new genus
and species, and discuss the characters used to place it
within the Hypoptopomatinae.
MATERIALS AND METHODS
Methodology and terminology for linear measurements
follow Pereira et al. (2007), with the addition of internarial
width, measured between the mesial margins of both
anterior nares. Morphological measurements were made
point-to-point to the nearest 0.1 mm with digital calipers
under a dissecting scope. Body plate counts and nomencla-
ture follow Schaefer (1997). Measurements of bilaterally
symmetrical features were made on the left side of the body
whenever possible. Morphometric data are expressed as
percents of the standard length (SL), except subunits of the
cephalic region which were expressed as percents of head
length (HL). Morphometric data are presented separately
for two classes of body length in order to allow proper
comparisons of small and large specimens. Vertebral counts
include all vertebrae, including the five centra modified into
the Weberian apparatus, with the compound caudal cen-
trum (PU1+U1) counted as one element. Vertebral elements
were counted in cleared-and-stained specimens only. Oste-
ological examinations were performed on specimens cleared
and double-stained for bone and cartilage (CS) according to
the procedure of Taylor and Van Dyke (1985). Institutional
abbreviations for specimens examined are those listed in
http://www.asih.org/node/204. Specimens examined for
this study are those listed in Lehmann (2006) and Pereira
(2009), with the addition of those listed below under Material
Plesioptopoma, new genus
Type species.—Plesioptopoma curvidens, new species
Diagnosis.—Distinguished from non-Hypoptopomatinae lor-
icariids by having the ventral surface of the coracoid with an
exposed area supporting a few odontodes laterally, close to
the pectoral-fin insertion (Fig. 1), and, except from Kro-
nichthys, by having the odontodes on the ventral surface of
the pelvic-fin unbranched ray distinctly bent and turned
mesially (Fig. 2). Distinguished from all hypoptopomatines,
except Parotocinclus prata, by having the premaxilla and
dentary tooth series strongly curved mesially, in such a way
that the mesial portion of the tooth series in both sides are
turned and run parallel to each other (Fig. 3; vs. tooth series
straight or slightly curved). It is also distinguished from the
remaining hypoptopomatines, except Pseudotocinclus,by
having the caudal peduncle distinctly quadrangular in
cross-section (vs. caudal peduncle ovoid in cross-section),
and except from Gymnotocinclus by having the anterior
margin of the snout devoid of dermal plates (Fig. 4; vs.
anterior margin of snout plated).
Etymology.—The genus name Plesioptopoma is a combination
of the Greek plesion, meaning primitive, and optopoma, the
root of Hypoptopoma, type-genus of the subfamily, in
reference to the putative basal position of the new taxon
among the hypoptopomatines.
Plesioptopoma curvidens, new species
Figure 1, Table 1
Holotype.—MCP 46286, 82.8 mm SL, male, Brazil, Minas
Gerais, Cristiano Otoni, Rio Paraopeba, upper Rio Sa˜o
Francisco drainage, at old bridge ca. 100 m W of highway
BR-040, 20u499110S, 043u489470W, R. E. Reis, E. H. L. Pereira,
and P. Lehmann, 8 October 2004.
Paratypes.—MCP 36861, 8 (28.8–74.7 mm SL) +2 CS (29.2–
38.0 mm SL), AMNH 253202, 3 (29.0–36.5 mm SL), collected
Laborato´ rio de Sistema´tica de Vertebrados, Pontifı´cia Universidade Cato´ lica do Rio Grande do Sul, Av. Ipiranga, 6681, Caixa Postal 1429,
90619-900 Porto Alegre, RS, Brazil; E-mail: (RER) email@example.com; and (EHLP) firstname.lastname@example.org.
Laborato´ rio de Ictiologia, Universidade do Vale do Rio dos Sinos, Av. Unisinos, 950, 93022-000 Sa˜o Leopoldo, RS, Brazil; E-mail:
Submitted: 13 May 2011. Accepted: 19 September 2011. Associate Editor: S. A. Schaefer.
F2012 by the American Society of Ichthyologists and Herpetologists DOI: 10.1643/CI-11-068
Copeia 2012, No. 1, 6–11
with the holotype; MNRJ 21426, 3 (53.2–79.3 mm SL) +1CS
(59.3 mm SL), same locality as the holotype, F. A. G. Melo,
P. A. Buckup, and M. R. S. Melo, 24 February 2000.
Diagnosis.—Same as for genus.
Description.—Proportional measurements and counts in
Table 1. Medium-sized loricariid with standard length of
adult measured specimens 53.2–82.8 mm SL. Body elongate
and moderately depressed, progressively tapering from
cleithrum to end of caudal peduncle. Dorsal profile of body
gently convex, rising from snout tip to origin of dorsal fin
and then descending to end of caudal peduncle. Greatest
body depth at dorsal-fin origin. Least body depth at
shallowest part of caudal peduncle. Head and predorsal
region without conspicuous crests; dorsal and ventral series
on lateral plates strongly bent posteriorly and with distinct
series of odontodes forming conspicuous crests. Trunk
horizontally oval in cross-section, caudal peduncle strongly
flattened dorsally and ventrally becoming approximately
hexagonal at anal-fin level and quadrangular before the
caudal fin. Ventral profile almost straight between snout tip
and pelvic girdle, slightly elevating posteriorly along anal-
fin base, almost straight along caudal peduncle. Lateral-line
canal in median series complete, pored tube visible from
compound pterotic to last plate in middle lateral series. Mid-
dorsal and mid-ventral series of lateral plates incomplete,
terminating 6–10 plates before the caudal fin. Dorsal surface
of body covered by plates except for small naked area
around dorsal-fin base and opening of swimbladder capsule
posteroventrally to compound pterotic. Ventral surface of
head around lips, portion between pelvic-fin insertions
and around anal fin naked. Abdomen covered by small,
embedded platelets, irregularly arranged from pectoral
girdle to insertion of pelvic fins and between pelvic-fin
bases. Lateral abdominal plates absent. Small portion of
Fig. 1. Plesioptopoma curvidens, MCP 46286, holotype, 82.8 mm SL, male, Brazil, Minas Gerais, Cristiano Otoni, Rio Paraopeba, upper Rio Sa˜o
Francisco drainage, at old bridge ca. 100 m W of highway BR-040, 20u499110S, 043u489470W. White arrow points to exposed area of coracoid.
Reis et al.—New loricariid genus 7
pectoral girdle exposed ventrally next to pectoral-fin
insertion; sometimes one, usually few odontodes attached
to coracoid visible externally; girdle covered medially by
skin and abdominal platelets. Arrector fossa completely
Head moderately depressed; broadly round in dorsal
view with snout slightly squarish. Interorbital space straight
or slightly convex; superior margin of orbit not elevated.
Parieto-supraoccipital slightly elevated posterior to orbit.
Posterior tip of parieto-supraoccipital without enlarged or
raised odontodes even in smaller individuals. Snout tip with
large area of naked skin, devoid of odontodes. Rostral and
anterior postrostral plates absent; two large postrostral plates
present anterior to preoperculum. Preoperculum exposed;
canal-bearing lateral cheek plate with unbranched canal.
Adult specimens with well-developed soft fleshy tissue
extending along snout tip and ventral portion of head. Eye
small, dorsolaterally placed. Iris operculum absent or very
small. Nostrils at posterior terminus of pair of elongate,
shallow depressions beginning close to snout tip, ovoid,
slightly longer than wide, positioned closer to anterior
margin of orbit than to snout tip. Oral disk roughly circular;
lips well developed, occupying most of ventral surface of
head. Lower lip short, extending posteriorly to end of canal-
bearing lateral cheek plate or between that point and
anterior margin of pectoral girdle, upper lip wide and fleshy.
Both lips densely covered by minute papillae; decreasing in
size toward edge in lower lip. Posterior edge of lower lip
smooth or slightly fringed. Maxillary barbel short, mostly
adnate to lower lip and with very small free portion distally.
Tooth-bearing cup of both premaxilla and dentary wide,
with strongly curved series of teeth that run parallel to each
other mesially and diverge laterally (Fig. 3). Teeth small and
robust; asymmetrically bifid, medial cusp broad. Lateral cusp
small and pointed, reaching approximately half length of
medial cusp. Accessory patch of unicuspid teeth on both
premaxilla and dentary bones absent.
Dorsal fin originating slightly anterior to vertical line
passing through pelvic-fin origin. Dorsal fin short, reaching
three plates behind its base when adpressed. Nuchal plate
exposed, not covered by skin. Dorsal-fin spinelet transverse-
ly oval-shaped, platelike, wider than base of dorsal spine.
Dorsal-fin locking mechanism non-functional. Dorsal spine
moderately flexible, followed by seven branched rays.
Adipose fin absent. One to four median azygous platelets
between contralateral plates of the dorsal lateral series
located at adipose-fin place. Pectoral fin moderate in size,
with curved and flattened spine and six branched rays, first
longest; subsequent branched rays decrease gradually in size.
Posterior margin of pectoral fin slightly round, overlapping
pelvic-fin origin when adpressed. Pectoral-fin axillary slit
absent. Pelvic fin with one unbranched and five branched
rays, reaching anal-fin origin when adpressed in males,
reaching to point midway between anus and anal-fin origin
in females. Pelvic-fin unbranched ray depressed, covered
with minute odontodes ventrally and laterally; odontodes
on ventral margin strongly turned mesially (Fig. 2). Well-
developed dermal flap along posterodorsal margin of
thickened first pelvic-fin unbranched ray, extending to ray
tip in mature males; absent in females. Pelvic-fin flap
slightly higher near fin base. Anal fin long with one
Fig. 2. Pelvic fin of Plesioptopoma curvidens, MCP 46268, 82.8 mm SL,
ventral view. Unbranched pelvic-fin ray with odontodes bent and turned
mesially. Scale 55 mm.
Fig. 3. Premaxillary tooth series of Plesioptopoma curvidens, MCP
36861. Scale 51 mm.
Fig. 4. Anterior head of Plesioptopoma curvidens, MCP 36861,
38.0 mm SL, lateral view. Scale 55 mm.
8Copeia 2012, No. 1
unbranched and five branched rays; distinctly larger in
males than in females. Caudal fin forked to slightly concave;
upper lobe slightly longer than lower; one upper un-
branched, 14 branched, and one lower unbranched rays.
Vertebral centra 31(3), pleural ribs present on centra 6–14(2)
Color in alcohol.—Ground color of dorsal surface of head and
body light to dark brown. Cheeks, anterior margin of snout,
area between nostrils and orbits, and compound pterotic
covered with small, irregularly shaped, black or dark brown
dots. Dark dots on cheeks and compound pterotic usually
coalesced to form a darker area in juveniles. Flanks,
including mid-dorsal, median, and mid-ventral series of
lateral plates darkened, forming inconspicuous dark stripe
from head to caudal fin. One conspicuous dark brown
saddle immediately posterior to dorsal-fin base, coalesced
with lateral stripe. Second indistinct dark saddle at adipose-
fin location sometimes present. Light to dark brown
ventrally, darker on caudal peduncle. All fins with several
dark brown dots arranged in few irregular series.
Sexual dimorphism.—Adult males of Plesioptopoma curvidens
can be distinguished from females by the following sexually
dimorphic characters: genital papilla posterior to the anus
present (vs. absent in females); pelvic fin reaching anal-fin
origin when adpressed (vs. reaching to point midway
between anus and anal-fin origin in females); well-developed
dermal flap along posterodorsal margin of unbranched, first
pelvic-fin ray (vs. absent in females); and anal fin longer
(19.1–20.5%SL vs. 16.1%SL in females). Four adult males and
one adult female examined (Table 1).
Table 1. Morphometrics of Holotype and Paratypes of Plesioptopoma curvidens, for Large (n=5) and Small (n=10) Specimens. Values are given as
percents of standard length or head length. SD =standard deviation, H =holotype.
Specimens above 53 mm SL Specimens below 38 mm SL
H Min Max Mean SD Min Max Mean SD
Standard length (mm) 82.8 53.2 82.8 73.3 28.8 37.5 33.5
Percents of standard length
Head length 32.0 32.0 32.9 32.6 0.35 33.1 36.3 34.6 1.06
Predorsal length 41.4 41.4 42.9 42.4 0.60 41.6 44.7 42.7 0.86
Postdorsal length 46.9 45.4 47.5 46.5 0.77 43.7 46.9 45.4 1.07
Preanal length 57.9 57.9 61.4 59.2 1.37 58.1 60.5 59.2 0.77
Dorsal-fin spine length 25.0 22.9 25.0 24.3 0.98 23.1 25.8 24.4 0.84
Anal-fin spine length 20.2 16.1 20.6 19.2 1.81 16.9 19.1 18.4 0.75
Pectoral-fin spine length 19.8 18.1 20.4 19.3 0.98 16.6 19.1 17.6 0.91
Ventral-fin spine length 20.3 18.3 21.3 19.9 1.09 13.8 17.5 15.8 1.19
Upper caudal-fin ray – 25.8 28.8 27.6 1.55 17.2 33.4 28.0 5.18
Lower caudal-fin ray 25.2 21.3 25.9 24.7 1.92 26.3 31.2 28.2 1.64
Trunk length 14.7 14.7 16.6 15.2 0.80 15.1 17.0 15.8 0.66
Abdominal length 20.9 20.9 23.1 22.0 0.99 19.8 22.2 21.1 0.74
Cleithral width 25.0 24.5 25.0 24.8 0.22 23.2 25.1 24.1 0.65
Body depth as dorsal-fin origin 17.9 16.4 20.6 18.7 1.64 15.1 17.7 16.7 0.88
Body width at dorsal-fin origin 19.7 17.9 23.5 20.2 2.14 14.8 21.1 17.9 1.56
Body width at anal-fin origin 13.4 12.5 15.1 13.9 1.02 10.3 12.9 11.8 0.90
Caudal peduncle length 42.9 39.8 42.9 41.3 1.17 39.5 42.6 41.0 0.94
Caudal peduncle depth 7.9 7.9 8.8 8.3 0.36 7.9 9.1 8.5 0.42
Caudal peduncle width 4.7 4.7 5.6 5.2 0.43 4.5 6.0 5.2 0.43
Percents of head length
Snout length 58.9 53.8 59.3 57.2 2.31 49.5 55.4 51.0 1.80
Orbital diameter 11.3 10.5 13.1 11.7 0.98 12.9 14.9 14.0 0.68
Interorbital width 35.5 32.4 36.0 34.5 1.58 34.7 39.7 36.5 1.49
Internarial width 12.8 10.3 12.8 11.9 1.13 11.9 16.7 13.8 1.81
Head depth 47.5 46.3 49.2 47.6 1.22 43.4 47.9 45.8 1.41
Mandibulary ramus 12.8 11.1 13.9 12.6 1.28 10.8 13.6 11.9 0.90
Premaxillary teeth right 21 18 23 20.2 2.17 16 20 18.4 1.26
Premaxillary teeth left 22 20 23 21.2 1.30 16 21 19.2 1.69
Dentary teeth right 20 15 20 17.8 2.17 11 20 15.0 2.51
Dentary teeth left 17 17 21 18.0 1.73 10 22 16.1 3.52
Plates in median lateral series 27 27 27 27.0 0.00 26 27 26.9 0.32
Plates as dorsal-fin base 5 5 6 5.2 0.45 5 5 5.0 0.00
Plates at anal-fin base 4 3 4 3.4 0.55 3 3 3.0 0.00
Plates between anal and caudal 12 11 12 11.8 0.45 12 13 12.2 0.42
Reis et al.—New loricariid genus 9
Distribution and habitat.—Plesioptopoma curvidens is only
known from the type locality, the upper portion of the Rio
Paraopeba, a tributary to the upper Rio Sa˜o Francisco near
Cristiano Otoni, Minas Gerais, Brazil (Fig. 5). The Rio
Paraopeba at the type locality is a small stream of about 2–
4 meters wide and up to 0.5 meters deep. The water was clear
but heavily polluted by organic sewage, had fair amounts of
marginal, submerged, and emergent vegetation, and the
bottom was mostly sandy with patches of gravel and pebbles.
Etymology.—The specific epithet curvidens is from the Latin
curvus, meaning curved, bent, and dens, meaning tooth, in
allusion to the strongly curved tooth series in both the
premaxilla and dentary. A noun in apposition.
Plesioptopoma is a phenotypically remarkable taxon in that it
shows external similarity to some hypostomines or neople-
costomines. Despite the external similarity to other subfam-
ilies and its larger size compared to most other hypoptopo-
matines, Plesioptopoma is unambiguously assigned to that
subfamily based on the possession of five derived features.
The Hypoptopomatinae were most recently diagnosed in
Schaefer (1998), based on six derived characters. Plesiopto-
poma shares three of those six characters: (1) Open nasal
capsule (character 5); is found in most Hypoptopomatines,
where the lateral ethmoid does not form a complete capsule
around the nasal organ. In Plesioptopoma the lateral ethmoid
is well developed but the nasal capsule is open laterally. (2)
Enlarged fenestrae on the compound pterotic (character 10);
present in Plesioptopoma (Fig. 4). (3) Metapterygoid channel
present (character 13); a condition shared by Plesioptopoma.
This condition, however, is widespread among neoplecos-
tomines and other subfamilies, and is likely a plesiomorphy
among the hypoptopomatines.
In the remaining three characters reported by Schaefer
(1998), Plesioptopoma exhibits the plesiomorphic state: (4)
Pectoral skeleton arrector fossa either partially or completely
closed by a ventral lamina of the coracoids (character 30);
arrector fossa in Plesioptopoma is completely open. (5)
Presence of a median rostral plate on the snout (character
34); is not shared by Plesioptopoma, which is devoid of
dermal plates on the anterior snout border. (6) Enlarged
snout odontodes (character 39); also absent in the new
genus because of the absence of dermal plates on anterior
One additional character not included by Schaefer (1998)
that diagnoses the hypoptopomatines was also found in
Plesioptopoma. Contrary to all other loricariids, the hypop-
topomatines possess the pectoral girdle exposed ventrally,
either totally or in part. The ventral surface of the coracoid
of Plesioptopoma shows a small area exposed and supporting
a few odontodes laterally, close to the pectoral-fin insertion
(Fig. 1), most of the pectoral girdle being covered by skin
and dermal plates medially.
A second, previously unrecognized, derived feature of
the hypoptopomatines, although also shared with the
ventral surface of the pelvic-fin unbranched ray distinctly
bent and turned mesially (Fig. 2). These mesially turned
odontodes help the fish grasp marginal leaves and plant
stalks with the pelvic fins and hold position in the water
current. Even those hypoptopomatines that are most
commonly found among stones (Eurycheilichthys,Epactiono-
tus, some Parotocinclus species) share this feature, as most of
them usually hang from marginal vegetation when young.
Thus, although Plesioptopoma shares an overall similarity
with some loricariids other than hypoptopomatines, and
especially Kronichthys, the presence of some, but not all,
diagnostic hypotopomatine characters suggests that the
species belongs with that subfamily, albeit at or near the
basal node of the group and not with any of the included
Among the neoplecostomines, Plesioptopoma is most
similar to Kronichthys, with whom it shares the narrow and
elongate body shape and the tooth series in both the
premaxilla and dentary strongly curved medially (Fig. 3).
However, Kronichthys does not exhibit the hypoptopomatine
characters listed above, and thus the shared characters are
best interpreted as homoplasies at this time. Conversely,
Plesioptopoma is distinguished from Kronichthys by not having
plates on the anterior snout border (vs. plates present); by
having the anterior border of the mesethmoid arrow-shaped
(vs. straight); by having two foramina on the hyomandibula
(vs. hyomandibular foramina absent); by not having an
accessory flange on the first epibranchial (vs. accessory flange
present); and by having a dorsal process on the anterior shelf
of the basipterygium (Fig. 6; vs. dorsal process absent).
Among the Hypoptopomatinae, Plesioptopoma is easily
diagnosed by possessing three distinguishing features: the
functional tooth series in both the premaxilla and dentary
are strongly curved medially, with the series running
parallel to each other medially (Fig. 3). This character is
shared by the species of the neoplecostomine Kronichthys
and, to a lesser extent, by the hypoptopomatine Parotocin-
clus prata. The new genus is further distinguished from
Parotocinclus prata, however, by lacking a rostral plate (vs.
rostral plate present), by having two postrostral plates
(Fig. 4; vs. four postrostral plates), and by the straight
anterior margin of the mesethmoid (vs. mesethmoid
pointed anteriorly). Plesioptopoma is also distinguished from
the remaining hypoptopomatines, except Pseudotocinclus,by
Fig. 5. Type locality of Plesioptopoma curvidens in the upper Rio
Paraopeba, Rio Sa˜ o Francisco basin, central Brazil.
10 Copeia 2012, No. 1
having the caudal peduncle distinctly quadrangular in cross-
section (vs. caudal peduncle ovoid in cross-section). It is
easily distinguished from Pseudotocinclus,however,by
having the first anal-fin pterygiophore covered by skin (vs.
exposed ventrally in front of the anal-fin unbranched ray)
and the ventral surface of pectoral girdle hardly exposed
laterally (vs. ventral surface of pectoral girdle widely exposed
laterally). Finally, the new genus is diagnosed among the
hypoptopomatines, except Gymnotocinclus, by having the
anterior margin of the snout devoid of dermal plates (Fig. 4;
vs. anterior margin of snout plated). It can be distinguished
from Gymnotocinclus, however, by having a connecting bone
and complete body plating (vs. connecting bone absent and
body plating extremely reduced).
The features Plesioptopoma shares with Gymnotocinclus and
Parotocinclus prata, basal members of the Hypoptopomatinae,
and the currently neoplecostomine Kronichthys,issuggestive
of its relatively basal position among the hypoptopomatines.
To uncover the phylogenetic relationships of Plesioptopoma is
beyond the objectives of the present paper. That, however, is
currently being investigated by the authors and thus deferred
to another paper.
Parotocinclus prata: MCP 28322, 18, 1 CS, Minas Gerais,
Presidente Olega´rio, Rio Sa˜o Francisco basin, Co´rrego
Altinas, ca. 10 km from Presidente Olega´ rio toward Galena;
MCP 27381, 4 paratypes, Minas Gerais, Presidente Olega´ rio,
Rio Sa˜o Francisco basin, Rio da Prata, creek tributary to
Pseudotocinclus juquiae: MCP 45129, 2 +2 CS, Sa˜o Paulo,
Juquitiba, creek at Fazenda Estio on road from Santa Rita to
Pseudotocinclus parahybae: MCP 45094, 4, Sa˜o Paulo, Pinda-
monhangaba, Rio Paraı´ba do Sul basin at Bairro Ribeira˜o
Grande, Co´ rrego do Convento; MZUSP 47581, 1 CS
paratype, Sa˜o Paulo, Pindamonhangaba, Rio Paraı´ba do Sul
basin, creek tributary to Ribeira˜o Grande at Fazenda Sa˜o
Sebastia˜o do Ribeira˜o Grande.
We are grateful to P. Buckup (MNRJ) for the loan of
specimens and for calling our attention to this material.
Thanks are due to the All Catfish Species Inventory (NSF-
DEB #0315963), which financed the MCP expedition
during which part of the type material was collected. EHLP
is partially financed by a Post-Doc fellowship from CNPq
(process #151624/2009-7), PLA is partially financed by
CNPq (process #151213/2009-7), and RER is partially
financed by CNPq (process #303362/2007-3).
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famı´lia Loricariidae (Ostariophysi: Siluriformes) com eˆn-
fase na subfamı´lia Hypoptopomatinae. Unpubl. Ph.D.
diss., Pontifı´cia Universidade Cato´ lica do Rio Grande do
Sul, Porto Alegre, Brazil.
Pereira, E. H. L. 2009. Relac¸o˜ es filogene´ticas de Neoplecos-
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Taylor, W. R., and G. C. Van Dyke. 1985. Revised
procedures for staining and clearing small fishes and
other vertebrates for bone and cartilage study. Cybium
Fig. 6. Pelvic girdle of Plesioptopoma curvidens, MNRJ 21426, dorsal
view. B, basipterygium; DP, dorsal process. Scale 52 mm.
Reis et al.—New loricariid genus 11