Notoglanidium depierrei (Daget 1978)

Geerinckx, Tom, Vreven, Emmanuel, Dierick, Manuel, Hoorebeke, Luc Van & Adriaens, Dominique, 2013, Revision of Notoglanidium and related genera (Siluriformes: Claroteidae) based on morphology and osteology, Zootaxa 3691 (1), pp. 165-191 : 178

Notoglanidium depierrei (Daget 1978)

( Figs. 3A, 3 B & 10C)

Platyglanis depierrei Daget 1978

Holotype. MNHN 1978.759: Ndjim, tributary of lower Mbam river, Sanaga basin, Cameroon; approx. 4° 48’ N, 11° 29’ E; 153 mm SL.

Paratypes. MNHN 1978.761–762: same locality; 2 spec., 49–108 mm SL.

Diagnosis. Notoglanidium depierrei differs from all congeners in an elongated postanal region, resulting in a higher vertebral count (47–50 vs. 36–40), a higher total number of anal-fin rays (25–28 vs. 9–17), and a smaller distance between the bases of the anal and caudal fins (4.6–6.9 vs. 10.3–18.6). It also differs from other species in the genus in having: a small pre-dorsal body depth in relation to standard length, i.e. 6.9–12.0% SL [vs. 12.2% SL or more in N. akiri , N. macrostoma , N. maculatum , N. thomasi and N. walkeri (Table 4)]; an average number of soft dorsal-fin rays (9 or 10) [vs. 7 in N. akiri , N. boutchangai and N. macrostoma , and more in N. maculatus (16–22), N. thomasi (12–16) and N. walkeri (11–15)]; a rather small interorbital distance (18.2–23.7% HL) [vs. larger in N. akiri (24.1–32.8% HL), N. macrostoma (28.0–36.6%), N. maculatum (35.3–36.8% HL), N. thomasi (41.0–46.7% HL) and N. walkeri (27.8–33.3% HL)]; an average combined premaxillary tooth plate width (18.2–29.1% HL) [vs. 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), and larger in N. macrostoma (33.5–41.7% HL)].

Description. Body elongate, with depth varying little from head to body (pre-dorsal body depth 6.9–11.3% SL, minimal caudal peduncle depth 6.4–7.9% SL, head depth 31.8–44.2% HL). Branchiostegal membranes mostly fused. 9 or 10 branchiostegal rays. Large total number of vertebrae: 47–50. Adipose fin low and rather short, well separated from the dorsal, which has a short spine (2.5–3.7% SL) and 9 or 10 branched rays. See also Table 4.

Colouration in life. Uniform greyish brown dorsally, pale to whitish ventrally. There are no spots or markings on the body or the fins.

Maximum size recorded. 153 mm SL.

Etymology. Named in honour of D. Depierre, collector of the type specimens (Daget 1978).

Distribution. Known only from the type locality in the Sanaga basin ( Fig. 13 ).

Figures

FIGURE 13. Distribution of all * documented specimens of Notoglanidium species known by the authors (* not exhaustive for N. macrostoma).

FIGURE 3. A, Dorsal and B, lateral view of the skull region of Notoglanidium depierrei (holotype, MNHN 1978 - 759, 153 mm SL). C, Dorsal and D, lateral view of the skull region of N. macrostoma (MRAC 99 - 90 - P- 1912, 90 mm SL). CT scan reconstructions. Only selected structures indicated (see text for details). Scale bars = 5 mm.