Auchenoglanis biscutatus
Creators: name: Geerinckx, Tom
name: Vreven, Emmanuel
Publisher: name: Zenodo
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Actinopterygii
Siluriformes
Claroteidae
Auchenoglanis
Auchenoglanis biscutatus
Pimelodidae
Pimelodus
Pimelodus biscutatus

description: Auchenoglanis biscutatus (Geoffroy Saint-Hilaire, 1809)
(Figure 8A)
Pimelodus biscutatus Geoffroy Saint-Hilaire 1809
Auchenoglanis senegali Retzer 2010
Material examined
Holotype. MNHN 8969: Nile; 285 mm SL.
Other material. Specimens are listed per river basin (from west to east).
Senegal basin. MRAC 79-2-P-211 (holotype of A. senegalensis): camp Djoudj, Gorom River, Senegal; 16 ◦ 22 ′ N, 16 ◦ 16 ′ W; 156 mm SL. MRAC 79-2-P-212–214 (paratypes of A. senegalensis): same locality; 3 spm, 152–171 mm SL. MRAC 80-1-P-99: same locality; 217 mm SL. MRAC 73-5-P-2814 (paratype of A. senegalensis): Mbane, Lac de Guiers, Senegal; 16 ◦ 16 ′ N, 15 ◦ 48 ′ W; 117 mm SL.
Gambia basin. MRAC 81-3-P-381 (paratype of A. senegalensis): Ba-Foula-Bé, Gambia River, Senegal; 13 ◦ 02 ′ N, 13 ◦ 12 ′ W; 154 mm SL.
Niger basin. MRAC 73-12 -P-366: Mopti Nord (chenal domestique), Niger River, Mali; 14 ◦ 30 ′ N, 4 ◦ 12 ′ W; 160 mm SL. MRAC 73-12 -P-367–368: Mopti Sud (aval grille), Niger River, Mali; c.14 ◦ 30 ′ N, 4 ◦ 12 ′ W; 2 spm, 156–160 mm SL. MRAC 91-67 -P- 161: Okoso Creek (sandy floodplain channel), Niger River, Nigeria; 5 ◦ 08 ′ N, 6 ◦ 23 ′ E; 180 mm SL. MRAC 73-15 -P-995–998: Garoua, Benoué River, Cameroon; 9 ◦ 18 ′ N, 13 ◦ 24 ′ E; 4 spm, 161–179 mm SL.
Chad basin. MRAC 153906–907: Bahr-Sara, mouth of Mandoul River, Chad; c.08 ◦ 20 ′ N, 17 ◦ 46 ′ E; 2 spm, 133–145 mm SL. MRAC 154048–154050: Bahr-Tinga, Parc de Zakouma, Chad; c.10 ◦ 50 ′ N, 19 ◦ 45 ′ E; 3 spm, 145–216 mm SL. MRAC 154094: Fort Archambault, Chari River, Chad; 9 ◦ 09 ′ N, 18 ◦ 23 ′ E; 156 mm SL. MRAC 154174–175: Lake Iro, Chari River, Chad; 10 ◦ 09 ′ N, 19 ◦ 23 ′ E; 2 spm, 171–214 mm SL. MRAC 19980: Soueram, Chad; c.12 ◦ 28 ′ N, 14 ◦ 11 ′ E; 144 mm SL. MRAC 73- 26 -P-545–546: south of Hollom, Chad; c.11 ◦ 19 ′ N, 15 ◦ 04 ′ E; 2 spm, 211–223 mm SL. MRAC 73-15 -P-999–1000: Waza (bought), Cameroon; 11 ◦ 24 ′ N, 14 ◦ 34 ′ E; 2 spm, 137–149 mm SL. MRAC 73-15 -P-989–991: Guemé, Logone River, Cameroon; 10 ◦ 30 ′ N, 15 ◦ 11 ′ E; 2 spm, 111–176 mm SL. MRAC 73-15 -P-992: same locality; 199 mm SL. MRAC 73-15 -P-994: same locality; 154 mm SL. MRAC 73-16 -P-5488: Yagoua, Logone River (bought), Cameroon; 10 ◦ 21 ′ N, 15 ◦ 17 ′ E; 203 mm SL.
Diagnosis
Auchenoglanis biscutatus can be diagnosed from A. occidentalis by the large horizontal distance between the eye and the end of the supraoccipital process, being larger than the horizontal distance between the snout tip and the eye (104% or more; Figure 1C). Its adipose fin rises abruptly (versus very gradually). The tip of the maxillary barbel is not darker than the head.
Description
Head deep, with short, slightly pointed snout. Maxillary barbel always reaching eye, or even beyond it. Adipose fin high, at 8–12% SL. Branchiostegal membranes not fused; 9–10(11) branchiostegal rays. Width of premaxillary tooth plate 5–7% HL; both plates touching or not. Minimal caudal peduncle depth 11.5–13% SL. Dorsal fin with one rudimentary and one long spine, and 7 branched rays. Pectoral fin with spine and 8–10 branched rays, pelvic fin with 6 rays (5 branched), anal fin with 9–13 rays.
Colouration
Adults often uniformly brownish. Pigmentation degree variable, on average lighter than in A. occidentalis. Pattern, if present, consisting of darker spots, often in rows on the flanks, sometimes confluent in (marbled) juveniles, more rarely consisting of larger reticulate spots. Fins often with (smaller) dots.
Maximum size recorded
540 mm SL.
Distribution
West African rivers from Senegal to Chad basins, and more east in the Nile and Lake Turkana basins (Figure 9). Appears nowhere to be very numerous.
description: Published as part of Geerinckx, Tom & Vreven, Emmanuel, 2013, A re-evaluation of the species-level diversity within the catfish genus Auchenoglanis (Siluriformes: Claroteidae), pp. 2979-3010 in Journal of Natural History 47 (47 - 48) on pages 3000-3002, DOI: 10.1080/00222933.2013.802043, http://zenodo.org/record/4632001