A new species of suckermouth armored catfish, Pseudancistrus kwinti (Siluriformes: Loricariidae) from the Coppename River drainage, Central Suriname Nature Reserve, Suriname
Author
Willink, Philip W.
Author
Mol, Jan H.
Author
Chernoff, Barry
text
Zootaxa
2010
2332
40
48
journal article
10.5281/zenodo.193129
7883bfb7-5584-4278-9b5f-e34461a1d74d
1175-5326
193129
Pseudancistrus kwinti
,
new species
(
Figs. 1–2
,
Table 1
)
Common name:
Coppename Catfish
Previous citations:
Peckoltia
sp. (new),
Pseudancistrus barbatus
,
Berrenstein (2005)
Peckoltia
sp. 1,
Pseudancistrus barbatus
,
Mol
et al.
(2006)
Peckoltia
sp.,
Willink & Sidlauskas (2006)
Holotype
:
FMNH
116976, 94.3 mmSL,
Suriname
, Sipaliwini State, Coppename River at base of Sidonkroetoe-val rapids, Central
Suriname
Nature Reserve,
4º31’51”N
,
56º30’56”W
, J.H. Mol, B. Chernoff, P.W. Willink, and M. Cooperman,
9 March 2004
.
Paratypes
:
NZCS
F7066,
95.7 mm
SL,
Suriname
, Sipaliwini State, Rapids of Midden Coppename River, Central
Suriname
Nature Reserve,
4º12’53”N
,
56º35’54”W
, J.H. Mol, B. Chernoff, P.W. Willink, and M. Cooperman,
2 March 2004
;
FMNH
116975,
43.9 mm
SL,
Suriname
, Sipaliwini State, Coppename River at head of Tonckens-val rapids, Central
Suriname
Nature Reserve,
4º25’22”N
,
56º31’34”W
, J.H. Mol, B. Chernoff, P.W. Willink, and M. Cooperman,
23 February 2004
.
Diagnosis:
Pseudancistrus kwinti
can be diagnosed from all other described
Pseudancistrus
by the following combination of characters: dentary papillae absent (versus present in
P. coquenani
(Steindachner)
,
P. o r i n o c o
(Isbrücker
et al.
) (
Fig. 3
),
P. pectegenitor
Lujan
et al.
, and
P. yekuana
Lujan
et al.
), mid-dorsal plate row complete (versus incomplete in
P. genisetiger
Fowler
,
P. papariae
Fowler
, and
P. re u s
Armbruster & Taphorn), coloration mottled or with bars (versus dark with white spots in
P. barbatus
(Valenciennes)
,
P. corantijniensis
de Chambrier & Montoya-Burgos,
P. depressus
(Günther)
,
P. longispinis
(Heitmans
et al.
)
,
P. niger
(Norman)
,
P. nigrescens
Eigenmann
, and
P. sidereus
Ambruster
or base of plates dark and edges pale in
P. guentheri
(Regan))
, and hypertrophied odontodes along edge of snout (versus largely restricted to cheek plates in
P. brevispinis
(Heitmans
et al.
))
.
Description:
Morphometric data in
Table 1
. Ventral surface flattened. Lateral profile of snout relatively straight at approximately 45º angle. Profile curves from anterior of eye to supraoccipital, then increases slightly to dorsal-fin origin, the highest point on the body. Profile relatively straight and decreasing from dorsal-fin origin to caudal fin. Body relatively deep, dorsal-fin origin to pectoral-fin origin 30.3–32.0% of standard length. Median lateral plates 24–25. Caudal peduncle plate rows 5. Plates covered by odontodes, but not keeled. Hypertrophied odontodes along posterior edge of plate. Cheek plates evertible to ~20º from head. Abdomen without plates. No plates immediately around anus.
Dorsal profile of snout rounded. Head width widest at evertible cheek plates. Body narrows from evertible cheek plates to caudal fin. Caudal peduncle compressed horizontally. Head relatively smooth. Anterior orbital rim slightly elevated. Low ridge from tip of snout to between nares. Eyes directed dorsolaterally. Orbit diameter 16.6–22.4% of head length. Nares closer to eyes than to tip of snout. Hypertrophied odontodes along edge of snout, 15 (juvenile)–67 (adult) on evertible cheek plates. Hypertrophied odontodes straight and directed laterally.
All spines and rays on all fins with odontodes. Odontodes slightly larger on spines and unbranched rays. Pectoral fin
I6
, reaching posterior end of pelvic-fin base when adpressed. Spine stout. First three branched rays extend distal of tip of spine. Distal margin convex. Pelvic fin
i5.
Origin equal to second branched ray of dorsal fin, reaching posterior end of anal-fin base when adpressed. Unbranched ray hypertrophied and strengthed. First four branched rays extend distal of tip of unbranched ray. Distal margin convex. Anal fin
i4
(NZCS F7066 anal fin
i5
, but appears malformed). Origin equal to dorsal-fin termination, reaching middle of adipose fin when adpressed. First three branched rays extend distal of tip of unbranched ray. Distal margin convex. Dorsal fin
Ii7
, with I and i fused. Origin anterior of pelvic fin, reaching just posterior end of adiposefin origin when adpressed. Distal margin convex. Adipose fin I, not reaching caudal fin. Membrane extends beyond distal tip of spine. Distal margin convex. Caudal fin
i14
i. Base at approximately 65º angle, such that dorsalmost point of base is anterior of ventralmost point. Regardless of angle, caudal-fin ventral edge slightly longer than dorsal edge. Interior branched rays shorter than exterior unbranched rays, forming concave distal margin. Dorsal procurrent caudal-fin rays 5 and ventral procurrent caudal-fin rays
3 in
FMNH 116975.
TABLE 1.
Measurements of
Pseudancistrus kwinti
types (n = 3) in either percent of standard length or percent of head length. Measurements are as described in Armbruster (2003).
Holotype
Range Average SD Standard length (mm) 94.3 43.9–95.7 78.0 29.5
(In percent of standard length) |
Predorsal length |
45.5 |
45.5–48.3 47.1 |
1.5 |
Head length |
35.5 |
35.5–37.1 36.4 |
0.85 |
Head–dorsal length |
11.3 |
10.0–11.6 11.0 |
0.9 |
Cleithral width |
35.7 |
34.9–37.4 36.0 |
1.3 |
Head–pectoral length |
30.1 |
28.5–32.0 30.2 |
1.7 |
Thorax length |
22.2 |
22.2–24.9 23.4 |
1.4 |
Pectoral-spine length |
28.1 |
26.5–28.1 27.1 |
0.9 |
Abdominal length |
26.9 |
22.9–26.9 25.5 |
2.2 |
Pelvic-spine length |
26.4 |
25.4–26.7 26.2 |
0.7 |
Postanal length |
30.1 |
28.1–31.5 29.9 |
1.7 |
Anal-fin spine length |
12.8 |
10.4–12.8 11.7 |
1.2 |
Dorsal–pectoral depth |
30.3 |
30.3–32.0 31.4 |
1.0 |
Dorsal-spine length |
28.1 |
28.1–30.6 29.0 |
1.4 |
Dorsal–pelvic depth |
25.4 |
22.5–26.0 24.6 |
1.9 |
Dorsal-fin base length |
27.9 |
27.2–27.9 27.6 |
0.3 |
Dorsal–adipose depth |
9.8 |
8.6–13.0 10.4 |
2.3 |
Adipose-spine length |
11.8 |
9.8–11.8 10.5 |
1.1 |
Adipose–upper caudal depth |
14.0 |
13.4–14.6 14.0 |
0.6 |
Caudal peduncle depth |
16.3 |
15.9–16.3 16.2 |
0.3 |
Adipose–lower caudal depth |
26.4 |
24.8–26.4 25.9 |
0.9 |
Adipose–anal depth |
19.3 |
19.0–21.3 19.9 |
1.3 |
Dorsal–anal depth |
18.8 |
17.9–18.8 18.5 |
0.5 |
Pelvic–dorsal depth |
30.6 |
29.5–31.0 30.4 |
0.8 |
(In percent of head length) |
Head–eye length |
30.0 |
30.0–32.2 30.9 |
1.2 |
Orbit diameter |
16.6 |
16.6–22.4 18.7 |
3.2 |
Snout length |
68.0 |
58.0–68.0 64.2 |
5.4 |
Internares width |
20.9 |
12.1–20.9 17.7 |
4.8 |
Interorbital width |
47.0 |
32.0–49.8 42.9 |
9.6 |
Head depth |
70.4 |
70.4–72.8 71.8 |
1.3 |
Mouth length |
59.6 |
52.9–64.2 58.9 |
5.7 |
Mouth width |
75.9 |
55.5–75.9 68.1 |
11.0 |
Barbel length |
9.9 |
8.5–9.9 9.0 |
0.8 |
Dentary tooth cup length |
18.4 |
17.2–18.8 18.1 |
0.8 |
Premaxillary tooth cup length |
16.6 |
16.6–18.8 17.7 |
1.1 |
Mouth extending ¾ of distance across head. Premaxillary- and dentary-tooth rows gently curved. Premaxillary teeth 46–53. Dentary teeth 45–61. Teeth villiform, on stalks, bicuspid, with lateral cusp 50–85% of the length of the medial cusp. Buccal papilla present. Dentary papillae absent. Lips not extending beyond margin of head. Posterior lobe longer than anterior lobe. Ventral surface of both lobes covered with papillae. Papillae fairly uniform in size, slightly larger towards mouth. Lip margins smooth except for slight unevenness caused by papillae. Posterior lip margin reaching level of opercular opening. Barbels short, not reaching halfway point to posterior margin of lip.
FIGURE 1.
Dorsal, lateral, and ventral views of juvenile
Pseudancistrus kwinti
, paratype, FMNH 116975, 43.9 mm SL.
FIGURE 2.
Dorsal, lateral, and ventral views of adult
Pseudancistrus kwinti
, holotype, FMNH 116976, 94.3 mm SL.
FIGURE 3.
Mouth of hypothetical
Pseudancistrus
showing the locations, when present, of the single buccal papilla (BP) and two dentary papillae (DP). The four tooth rows are filled in.
Color in alcohol:
Juvenile head brown with two faint pale bars (
Fig. 1
). First bar from ventralposterior corner of eye to cheek plate. Second bar from posterior margin of supraoccipital to base of pectoral spine. Body with alternating dark and pale bars. The four dark bars approximately twice as wide as pale bars (three or four plates wide versus one or two). Bars angled such that dorsal portion is anterior to ventral portion. First pale bar starts at dorsal-fin origin. Second pale bar starts near third branched ray of dorsal fin. Third pale bar starts at dorsal-fin termination. Fourth pale bar starts at adipose-fin origin. Ventral half of body slightly fainter than dorsal half.
Dorsal fin with three alternating dark and pale bars confluent with the bars on the body. Distal margin pale. Adipose fin with one distal dark bar. Within dark bar, leading edge of fin and margin between fin and body are more heavily pigmented. Caudal fin with two wide alternating dark and pale bars. Caudal-fin base pale. Caudal-fin distal margin a wide dark bar with a very narrow hyaline edge. Pectoral fin brown; less pigmented at base and distal margin, forming two faint pale bars and dark central bar. Pelvic fin brown; less pigmented at base and distal margin, forming two faint pale bars and dark central bar, each confluent with bars on body. Anal fin less pigmented at base and distal margin, forming two faint pale bars and dark central bar, each confluent with bars on body.
Barbels and posterior margin of lip pigmented. Oral disk pale. Abdomen pale with moderate amount of pigmentation along sides between pectoral and pelvic fins. Ventral plates pigmented in the same alternating bar pattern as lateral plates.
Adult head and body brown, with some pale mottling (
Fig. 2
). Juvenile pale bands faded with some remnants present, especially at junction of dorsal and mid-dorsal plate rows. Ventral half of body slightly fainter than dorsal half.
Dorsal fin with four alternating pale and dark bars. Tip of unbranched ray and first branched ray pale, but tips of all other rays dark. Adipose fin spine dark except for pale tip. Distal adipose membrane adjacent to spine pale, otherwise dark. Caudal fin between base and fork with three to four alternating pale and dark bars. Caudal-fin base pale. Bars partially interconnected in
holotype
(
Fig. 2
). Caudal-fin tips with additional paledark-pale sequence. Pectoral fin brown, slightly mottled. Pelvic fin with three alternating dark and pale bars. Pelvic-fin base dark. Proximal half of anal fin dark, distal half pale.
Barbels and posterior margin of lip pigmented. Oral disk pale. Abdomen pale with moderate amount of pigmentation along sides between pectoral and pelvic fins. Ventral plates uniformly pale with slight pigmentation.
FIGURE 4.
Map of major rivers in Suriname and collection localities for
Pseudancistrus kwinti
(star = holotype, circle = paratype).
Sexual dimorphism:
In most species of
Pseudancistrus
, the hypertrophied odontodes along the snout are relatively longer in males than in females (
Armbruster, 2004
). This appears to be the case in
P. k w i n t i
, although the sample size is small.
Range:
Pseudancistrus kwinti
is only known from the Coppename River drainage, Sipaliwini,
Suriname
(
Fig. 4
). These localities are within the Central
Suriname
Nature Reserve.
Habitat:
Pseudancistrus kwinti
was collected in rapids (
Fig. 5
). Substrate was rubble, boulders, and cracked bedrock with patches of the aquatic plant
Podostemaceae
. Clear water. Swift current.
Etymology:
The species-group name,
kwinti
, refers to the
Kwinti
people that live along the Coppename River and traditionally fish the area in which the new species was discovered (
Hoogbergen, 1992
). The gender of
Pseudancistrus
is masculine. The species-group name is treated as a noun in apposition.