Diagnosis |
Diagnosis: Chiloglanis waterloti is distinguished from all West African congeners, with the exception of C. longibarbis, in having fewer mandibular teeth in the functional row; it is distinguished from C. longibarbis in having shorter maxillary barbels and shorter medial mandibular barbels (Ref. 116018).
Description: A moderate-sized Chiloglanis; 48.0 mm maximum standard length observed; body dorsally depressed anteriorly; laterally compressed posteriorly; pre-dorsal angled toward snout; pre-orbital convex; post- dorsl body moderately angled ventrally towards caudal fin; pre-anal profile horizontal; post-anal horizontal to ventrally sloping towards caudal fin (Ref. 116018). Unculiferous tubercles scattered across body; concentration higher near head; lateral line complete; arising above level of orbit and sloping ventrally towards caudal fin; urogenital papillae sexually dimorphic; elongate in males; reduced and separated from anus by shallow invagination in females (Ref. 116018). Head depressed; gill membranes broadly united; gill openings restricted; opening slightly dorsal of pectoral-fin origin to level of mid-orbit; occipital-nuchal shield covered and visible through skin; eyes moderate; horizontal axis longest; orbits without free margins; anterior and posterior nares equidistant; mid-snout; posterior nares with elongated anterior and medial flaps (Ref. 116018). Mouth inferior; upper and lower lips united to form oral disc; oral disc moderate in size, its width 17.4-23.0% of standard length; wider than long; covered in papillae (Ref. 116018). Barbels in three pairs; maxillary barbel originating from posterolateral region of disc; unbranched; moderate in length, 20.4-37.8% of head length; lateral and medial mandibular barbels moderate; incorporated into lower lip; positioned on both sides of midline cleft on posterior margin of oral disc; lateral barbels, 11.5-22.2% of head length, nearly twice the length of medial barbels (Ref. 116018). Premaxillary teeth "S"-shaped; exposed tips brown; 39-70 teeth in three rows on ovoid tooth pads; secondary premaxillary teeth scattered on posterior surface of premaxillae; tertiary teeth small and needle-like; inserted near midline on dorsal edge of toothplate; mandibular teeth in 1-2 rows; "S"-shaped and bunched near midline; functional, anterior, row usually contains eight brown tipped teeth (Ref. 116018). Dorsal-fin origin just posterior to anterior third of body; dorsal fin with small spinelet, spine, and 5-6 rays; dorsal spine relatively long, 13.3-20.0% of standard length; anterior margin of spine smooth, three small notches distally; posterior margin smooth distally, four notches proximally; adipose fin moderate in length, 13.9-21.4% of standard length; margin convex; small notch posteriorly; caudal fin forked with rounded lobes; lower lobe slightly longer than upper lobe; count i,7,8,i; anal-fin origin posterior to origin of adipose fin; extending well beyond adipose-fin terminus; margin convex; count iii,6-7; pelvic-fin origin at vertical midway between dorsal and adipose fin; extending to anal-fin origin; margins convex; count i,6; pectoral fin with smooth spine; relatively long, 16.7-24.8% of standard length; count I,8-9 (Ref. 116018). Postcleithral process sexually dimorphic; elongate, spatulate in males; females possessing a shorter, pointed process; body size sexually dimorphic; females attaining larger standard lengths than males (Ref. 116018).
Colouration: Live colouration: body with light yellowish-brown ground colour with overlying melanophores, fins yellow (Ref. 116018). The colouration of preserved specimens in dorsal view, body a dark brown with mottling of medium brown; lighter areas anterior to dorsal-fin origin, and at adipose-fin origin and terminus; head dark brown; scattered spots of medium brown, dark melanophores spread throughout; in lateral view, body a yellow-buff; overlain by medium and dark browns above the midline, light areas more prominent below midline, dark areas extending to near the pelvic- and anal-fin origins, and around the caudal peduncle; small black melanophores scattered across sides, readily observed below midline; ventral surface yellow-buff; scattered melanophores, more numerous near pelvic and pectoral-fin origins; oral disc and barbels cream (Ref. 116018). Dorsal and pectoral spines and rays light brown totranslucent; bases of dorsal, pectoral, and anal fins marked with medium brown triangle; brown patches at mid-length of pectoral, dorsal, and anal fins; pelvic fins cream; small brown spot at mid-length; adipose fin cream; brown semicircular marking at origin and near base at mid-length; caudal fin cream; two dark areas near base and extending into the upper and lower lobes of the caudal fin (Ref. 116018). |