Notoglanidium walkeri Günther 1903

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 : 184-186

Notoglanidium walkeri Günther 1903

( Figs 6A, 6 B & 10I)

Syntypes. BMNH 1903.4.24.78–79: Ibbi river (near Beyin), Ghana; approx. 5°0’N, 2°38’ W; two spec., 92–99 mm SL.

Other specimens examined. MNHN 1980.1270: N'pedo river, Agnébi basin, Ivory Coast; 47 mm SL. MNHN 1970.14: Agnébi basin, Ivory Coast; approx. 5°19’N, 4°20’W; three spec., 32–72 mm SL.

Diagnosis. Notoglanidium walkeri differs from other species in the genus in having: an average interorbital distance (27.8–33.3% HL) [vs. smaller in N. boutchangai (17.2–23.4% HL), N. depierrei (18.2–23.7% HL), N. pallidum (20.0–23.3% HL) and N. pembetadi (17.4–24.0% HL), and larger in N. maculatum (35.3–36.8% HL) and N. thomasi (41.0–46.7% HL)]; a relatively small combined premaxillary tooth plate width (13.7–16.1% HL) [vs. larger in N. akiri (22.0–26.1% HL), N. boutchangai (30.1–35.3% HL), N. macrostoma (33.5–41.7% HL) and N. pembetadi (21.0–26.4% HL)]; a relatively large number of soft dorsal-fin rays (11–15) [vs. less in N. akiri (7), N. boutchangai (7), N. depierrei (9 or 10) and N. macrostoma (7), and more in N. maculatum (16–22)].

Description. Snout nor body much depressed (predorsal body depth 14.1–20.2% SL, minimal caudal peduncle depth 13.0–14.6% SL, head depth 53.6–66.0% HL). Branchiostegal membranes completely fused. Dorsal fin with short spine (3.2–7.0% SL). See also Table 4.

Colouration in life. Yellowish brown, with round dark spots scattered around body and fins.

Maximum size recorded. 99 mm SL.

Etymology. Named in honour of R.B.N. Walker, collector of the type specimens (Günther 1903).

Distribution. Known from the Ibi (Ibbi) River in Ghana, and the Agnébi (Agneby) basin in Ivory Coast ( Fig. 13 ).

Figures

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

FIGURE 6. A, Dorsal and B, lateral view of the skull region of N. walkeri (syntype, BMNH 1903.4.24.78 – 79, 92 mm SL). CT scan reconstructions. Only selected structures indicated (see text for details). Scale bars = 5 mm.