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Dorsal spines (total): 17-17; Dorsal soft rays (total): 11-12; Anal spines: 3-3; Anal soft rays: 9-10. Diagnosis: A medium-sized laterally spotted haplochromine separable from all previously described species of Otopharynx both by its unique melanin pattern and by its distinctive lower pharyngeal bone (Ref. 119408). The suprapectoral spot is rectangular, 2-2.5 scales high, longitudinally elongate, covering 7-8 consecutive scales starting with the seventh scale of the upper lateral line, extending vertically from just above the lateral midline to slightly above the upper lateral line; the supraanal and precaudal spots are conjoined, forming a continuous stripe, paler at its midlength in some specimens, from the level of the anal-fin origin to the base of the caudal fin; the lower pharyngeal bone is broadly triangular, somewhat heart-shaped, with numerous uniformly small, laterally compressed, crowded, bicuspid teeth (Ref. 119408).
Description: Deep-bodied, body depth 34.0-38.5% of standard length (Ref. 119408). Dorsal profile of snout straight, profile above eye straight to slightly concave, then evenly convex from nape to end of dorsal-fin base; premaxillary pedicels not prominent, their angle 42-49°, interorbital angle 39-43°, nuchal angle 24-36°; ventral profile nearly straight from caudal end of lower jaw to chest, irregularly convex from pelvic-fin origin to end of anal-fin base (Ref. 119408). Jaws equal anteriorly; lips neither thickened nor lobate; lower jaw somewhat flattened, the dentary walls appearing outwardly rotated; gape inclination 30-39°; lower jaw length-width ratio intermediate, the hemijaws, as seen from below, parallel and well separated posteriorly; lower-jaw underside angle 37-40°; snout acuteness 71-77°; eyes large, slightly oval, orbit length 32.8-34.3% of head length, vertical eye diameter 28.8-31.4% of head length; pupil rounded anteriorly and posteriorly; eye not reaching dorsal head profile (Ref. 119408). Caudal peduncle 15.0-18.1% of standard length, its length 1.3-1.6 times its depth (Ref. 119408). Soft dorsal and anal fins acutely pointed and elongated posteriorly, at least in males; caudal fin deeply emarginate; upper and lower lobes acutely pointed, subequal; pectoral fin long, 31.0-36.2% of standard length, acute, upper rays elongated, reaching level of anus; pelvic fins with first soft ray elongate, reaching base of first anal-fin spine in holotype and one paratype (Ref. 119408). Dental arcade broadly arched in each jaw; upper jaw with 53-62 teeth in outer row; anterior and lateral teeth unequally bicuspid, occasional tricuspid teeth laterally; posterior teeth unicuspid; anterior teeth of outer row loosely implanted, easily lost, leaving visible holes in lips; lower-jaw outer tooth row of haplochromis type, with 36-46 teeth; crowns as in upper jaw; inner teeth of both jaws unequally tricuspid, in 1-2 rows (Ref. 119408). Lower pharyngeal bone subtriangular; posterior contour of each half convexly curved, the halves meeting at nearly a 90° angle, giving a somewhat heart-shaped outline to the bone; horns short, thin, narrowing distally; median suture straight; keel short, deep, scarcely descending; dentigerous surface concave in lateral view; bone shallow in posterior view; teeth bicuspid, laterally compressed, uniformly small except for slightly larger teeth in posterior row; crowded, especially on posterior and lateral areas; teeth in posterior row 45-50; in each median column 11-16; in each oblique row 10-14 (Ref. 119408). Lacrimal bone bearing four neuromasts and five lateral-line pores, lacrimal notch distinct (Ref. 119408). Gill rakers 12-13, closely spaced, rather short, of nearly uniform length along lower limb of outer arch; unpigmented, completely lacking melanophores (Ref. 119408). Scales ctenoid; 35-36 in lateral line; lateral line discontinuous; upper section with downward kink 1-6 scales long, or absent; caudal fin scaled heavily to near tips of upper and lower lobes, stiffening them; scaled on basal one-half of middle-rays; soft dorsal and anal fins with a single small scale between bases of some rays; scales transition gradually in size from larger on belly to smaller on chest (Ref. 119408).
Colouration: Colouration in life unknown, but fresh subadult male specimens appear brownish on upper head, nape, and dorsum, silvery to white on the flanks and lower head surfaces; traces of about nine narrow gray vertical bars on flanks below dorsal-fin base; presence of the characteristic dark suprapectoral spot and posterior stripe; dorsal-fin lappets yellow; dorsal has dark-edged yellow maculae throughout, most distinct in soft part of fin; broad upper and lower leading edges of caudal fin are pale yellow, remainder of fin darker; anal fin bears about four oval yellow eggspots in two rows along middle and near distal edge of fin; pelvic fins yellow with white leading edges; pectoral fins are yellowish (Ref. 119408). Colouration in preservative: head and flanks brown above, becoming silvery below; head with distinct opercular spot and an indefinite dark oblique bar from below front of eye to rear half of upper jaw; underside of head and branchiostegal membrane brownish; suprapectoral spot a longitudinally elongate ectangle 2-2.5 scales high, covering 7-8 consecutive scales starting with seventh scale of upper lateral line, based just above lateral midline and reaching to one-half scale above upper lateral line; supraanal and precaudal spots united into a continuous stripe, which may or may not be paler at its midlength, from level of anal-fin origin to base of caudal fin; lower edge of stripe on scale row containing lower lateral line, which is one scale row lower than bottom of suprapectoral spot; about eight faint vertical bars visible on flanks; dorsal fin with series of dark-edged oval maculae between all spines and rays, more distinct in soft dorsal; lappets pale, but fin margin of largest paratype continuous, without lappets; caudal fin yellowish to brownish with indistinct marbling; anal and pelvic fins dark brown, anal with no eggspots; pectorals hyaline (Ref. 119408). |