Diagnosis |
Diagnosis: lateral line count of 38-43 scales; 16-17 closely packed gill-rakers along lower limb of first arch; extremely robust lower pharyngeal jaw with mill-like molariform teeth occupying at least 2/3 of dentigerous surface; third pore of mandibular laterosensory canal enlarged compared to size of preceding pores (Ref. 52346).
Description: deep bodied (Ref. 52307, 52346) and robust (Ref. 52346). Predorsal head profile rises steeply (Ref. 52307, 52346) at an angle of about 55-60° over snout to orbit where a fleshy interorbital bulge is usually developed (Ref. 52346). From orbit to origin of dorsal fin, head profile frequently slightly more steeply inclined, lending typical hump-backed appearance; greatest depth along body at origin of dorsal fin; from nape to caudal peduncle dorsum strongly recurved, although body is more or less flattened along ventrum; mouth usually a little oblique when closed; lips well developed but not noticeably fleshy or thickened; mouth frequently agape and asymmetrically twisted; lower pharyngeal jaw extremely robust (Ref. 52346). Maxillary not extending to below eye; 3 series of scales on cheek (Ref. 52971). 16-17 closely packed gill-rakers along lower limb of first arch; 3-4 elongate and simple hypobranchial rakers, remaining ceratobranchial rakers crenate and overlapping; epibranchial rakers rather broad and frequently bifurcate; vertebral apophysis well developed and robust, and of the standard Tylochromis type (Ref. 52346). 40-41 scales in longitudinal series; 7 scales between dorsal spine and lateral line; 27-29 scales in upper lateral line; 34-35 scales in lower lateral line; 2 scales between upper and lower lateral line (Ref. 52971). Upper branch of lateral line terminates well in advance of end of dorsal fin, usually about level of 7th-8th soft ray from free end; terminal canal bearing scales do not descend scale rows; dorsal and ventral branches of lateral line on caudal fin extend almost to fin periphery, and median branch often absent, but when present usually reaches only about halfway onto fin; dorsal fin spines increase rapidly to the fifth and then are more or less equal in length; anal fin rounded; pectoral fins extremely long and reaching middle of soft anal fin; first pelvic ray frequently produced but rarely reaches beyond level of vent; caudal fin strongly emarginate, but only finely scaled in dorsal and ventral fields (Ref. 52346).
Coloration: no details about living coloration known (Ref. 52307, 52346). Preserved juveniles often silvery with dusky grey snout and interorbital region, a dusky brown dorsal fin with numerous non-ocellate white spots, a small indistinct opercular blotch and a well marked nape-stripe, and 5-6 well developed vertical bars which extend down onto flanks to below midline; vertical barring less distinct and often entirely lacking in preserved adults; in large males longitudinal striations are associated with each scale row, particularly marked on caudal peduncle and dorsum; longitudinal striations only faintly evident in females; males with black upper lip and striking creamy white upper lip membrane, lower lip and gular region; in both sexes dark grey/brown dorsal fin membrane marked with numerous rows of small white non-ocellate spots, as is anal fin in males; male caudal fin striped and spotted in a typical manner (Ref. 52346). |