Revision of Notoglanidium and related genera (Siluriformes: Claroteidae) based on morphology and osteology
Author
Geerinckx, Tom
Author
Vreven, Emmanuel
Author
Dierick, Manuel
Author
Hoorebeke, Luc Van
Author
Adriaens, Dominique
text
Zootaxa
2013
3691
1
165
191
journal article
10.11646/zootaxa.3691.1.7
d11a5ae6-35e5-4293-9a85-82ac1c22175c
1175-5326
221669
1756334F-DAFB-4029-999A-9D8D6458B94E
Notoglanidium pembetadi
Vreven
et al.
2013
(
Figs. 5A, 5
B & 10G)
Holotype
.
MRAC A7-31-P-29: Kouilou-Niari River, Kouilou basin, just downstream from bridge of Dolisie (Loubomo)—Kibangou road, at Pont du Niari village,
Republic of the Congo
(
Congo-Brazzaville
);
3°33’34.2”S
,
12°20’28.2”E
;
150 mm
SL.
Paratypes
.
MRAC A7-31-P-30–32: same locality; 3 spec.,
115–140 mm
SL. MRAC A7-13-P-16–21: cf.
holotype
locality, at bridge;
3°33’18.8”S
,
12°20’35.0”E
; 6 spec.,
53–170 mm
SL. MRAC A7-13-P-42–44: cf.
holotype
locality, more downstream,
3°33’33.0”S
,
12°20’20.4”E
; 3 spec.,
123–162 mm
SL. AMNH 243475: cf.
holotype
locality, more downstream,
3°33’33.0”S
,
12°20’20.4”E
; 2 spec.,
166–179 mm
SL.
Other specimens examined.
MRAC 91-79-P-283, Kouilou-Niari River at Pont du Niari near Kibangou,
Republic of the Congo
(
Congo-Brazzaville
);
03°33’S
,
12°20’E
;
71 mm
SL. MRAC 91-79-P-284: same locality;
68 mm
SL. MRAC A5-36-P-119: cf.
holotype
locality;
3°33’18.8”S
,
12°20’35.0”E
;
111 mm
SL. MRAC A7-31-P-33: same locality as
holotype
;
101 mm
SL.
Diagnosis.
Notoglanidium pembetadi
differs from other species in the genus in having: a small predorsal body depth (8.2–11.6% SL) [
vs
. larger in
N. akiri
(19.5–24.4% SL),
N. macrostoma
(16.1–18.0% SL),
N. maculatum
(12.2–15.2% SL),
N. thomasi
(16.1–19.2% SL) and
N. walkeri
(14.1–20.2% SL)]; a large horizontal distance between the bases of the anal and caudal fins (15.7–18.6% SL) [
vs
. smaller in
N. boutchangai
(11.4–14.1% SL),
N. depierrei
(4.6–6.9% SL),
N. macrostoma
(10.3–13.6% SL) and
N. maculatum
(11.9–14.3% SL)]; a small interorbital distance (17.4–24.0% HL) [
vs
. larger in
N. akiri
(24.1–21.8% HL),
N. macrostoma
(28.0–40.4% HL),
N. maculatum
(20.0–23.3% HL),
N. thomasi
(41.0–26.4% HL) and
N. walkeri
(27.8–33.3% HL)]; an average combined premaxillary tooth plate width (21.0–26.4% HL) [
vs
. larger in
N. boutchangai
(30.1–35.3% HL) and
N. macrostoma
(33.5–41.7% HL), and smaller in
N. maculatum
(10.5–13.6% HL),
N. pallidum
(11.1–15.3% HL),
N.
thomasi
(11.9–18.2% HL) and
N. walkeri
(13.7–16.1% HL)]; an average number of soft dorsal-fin rays (10–13) [
vs
. seven rays in
N. akiri
,
N. boutchangai
and
N. macrostoma
, and 16–20 rays in
N. maculatum
].
FIGURE 5
. A, Dorsal and B, lateral view of the skull region of
Notoglanidium pembetadi
(MRAC A5-36-P-119, 111 mm SL). C, Dorsal and D, lateral view of the skull region of
N. thomasi
(BMNH 1976.11.12.84, 44 mm SL). CT scan reconstructions.
N. thomasi
specimen has been partially decalcified during preservation. Only selected structures indicated (see text for details). Scale bars = 5 mm.
Description.
Both head and body dorsoventrally flattened, with depth more or less constant from head to body (pre-dorsal body depth 8.2–11.6% SL, minimal caudal peduncle depth 9.3–12.9% SL, head depth 30.4–44.5% HL).
As
such, this is the only auchenoglanidine species where the caudal peduncle is often deeper than the anterior body half. Branchiostegal membranes variably fused, often not joint along the posterior halves (they may overlap). Combined premaxillary tooth plate of horseshoe-like shape (it is more cardiform or more widely crescent-like in other species). Adipose fin very low (1.1–2.6% SL). See also Table 4.
Colouration in life.
Dark brown with lighter ventral side. In some specimens 7–8 transverse series of black spots are present.
Maximum size recorded.
179 mm
SL.
Etymology.
The local Kunyi name for this species,
pembetadi
, has been chosen as species name (Vreven
et al
., 2013).
Distribution.
Known only from the Kouilou-Niari River [
Republic of the Congo
(
Congo-Brazzaville
);
Fig. 13
].