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Dorsal spines (total): 0-0; Dorsal soft rays (total): 10-10; Anal spines: 0-0; Anal soft rays: 15-18; Vertebrae: 33-34. Diagnosis: Brycinus epuluensis is distinguished from all species belonging to the macrolepidotus group by having a short snout, more than 3 times in head length vs. less than 3 times, and fewer premaxillary teeth, 6-7 vs. 8-11; it is distinguished from all species belonging to the longipinnis group by the absence of a fronto-parietal fontanelle in adults vs. fronto-parietal fontanelle always present, fewer lateral line scales, 18-22 vs. 25-36, and generally fewer anal-fin rays, iii,12-15 vs. iii,14-25; it is distinguished from aal species of the nurse group by having 6 or exceptionally 7 premaxillary teeth vs. 8-10, exceptionally 7 (Ref. 113515). The species is most similar to Brycinus imberi, from which it is mainly distinguished by fewer premaxillary teeth, 6-7 vs. 7-8, fewer lateral line scales, 18-22 vs. 21-31, and the presence of a black mid-lateral band (Ref. 113515).
Description: Body relatively slender, body depth at pelvic fins 27.9-34.0% of standard length, with greatest depth at vertical through dorsal-fin origin; dorsal profile straight along head, straight to slightly convex from occipital process to adipose fin, and slightly concave between adipose and caudal fins; ventral body profile convex between isthmus and anal-fin base, straight to convex along anal-fin base, and slightly concave between anal and caudal fins; caudal peduncle slightly longer than deep (Ref. 113515). Head narrow, its width 13-15% of standard length; fronto-parietal fontanelle absent in adults; snout rounded and relatively short, 7-10% of standard length, jaws isognathous, mouth terminal; orbit relatively large, length larger than snout length (Ref. 113515). Upper jaw with two tooth rows; six, exceptionally seven pluricuspid teeth in outer row of premaxilla, aligned in a single row, with a crenelated appearance and an enlarged median cusp flanked by one or two smaller cusps; inner row of premaxilla with eight stout teeth, anteriorly with two blunt broad-based cusps, and with a large primary cusp flanked by several secondary cusps on posterior edge; eight outer row teeth on lower jaw, each with a large central cusp and one to three secondary cusps on either side; two outermost teeth much smaller than median six; a single pair of small conical teeth on inner row of lower jaw (Ref. 113515). Dorsal fin located at midbody, origin of pelvic fin at same level or slightly anterior to dorsal-fin origin; dorsal-fin margin straight to slightly convex; caudal fin forked, with rounded lobes of equal size; adipose fin inserted above posterior border of anal fin; dorsal fin with ii,8 rays; anal fin with iii,12-15 rays (Ref. 113515). Body covered with well-developed, relatively large cycloid scales; lateral line completely pored, with a low number of scales: 18-22 (Ref. 113515). Gill rakers long and slender, 10-13 on upper branch, 13-17 on lower of first gill arch; total number of gill rakers 25-30; vertebrae 33-34, excluding Weberian apparatus (Ref. 113515).
Colouration: For preserved specimens: dorsal and dorso-lateral parts of head and body olive-brownish, ventral parts of body light brown to yellowish; head yellow to silvery below eye; a broad blackish mid-lateral band, spanning one to two scale rows, from operculum to caudal-fin base; in males, band more pronounced than in females; in small specimens band vague or even absent; humeral and caudal spots always present; all fins greyish, except pelvic fin yellowish (Ref. 113515). In life: dorsal parts of body olive-yellowish, ventro- lateral and ventral parts grey to silvery; dorsal, caudal and anal fins olive-yellowish; pectoral and pelvic fins grey to silvery; adipose fin orange; black mid-lateral band on flank in males, apparently absent in females; humeral and caudal spots present in both sexes (Ref. 113515). |