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Dorsal spines (total): 0-0; Dorsal soft rays (total): 15-18; Anal spines: 0-0; Anal soft rays: 15-18. Diagnosis: Nothobranchius chochamandai belongs to the N. brieni species-group, presenting the diagnostic characters of male colouration for this complex of the caudal and anal fins proximal portion spotted; absence of dark distal margin on dorsal fin; absence of spots on head; and absence of black posterior margin of scales (Ref. 97353). Nothobranchius chochamandai is distinguished from all other species of this complex, with the exception of N. symoensi by an anal fin with a light blue distal margin; distinguished from N. symoensi by a dorsal fin without a light blue distal margin, vs. present, and a caudal fin without dark submarginal band, vs. present; within the N. brieni species-group, N. chochamandai is characterised by the following unique combination of morphometrics: postorbital length 56-60% head length; snout length 16-19% head length; head width 65-69% head depth; caudal peduncle length 135-142% caudal depth (Ref. 97353).
Description: General body shape robust, laterally compressed and deep; head short, laterally compressed, deeper than wide; dorsal profile convex from tip of snout to base of last dorsal-fin ray, straight to slightly concave on caudal peduncle; ventral profile convex from lower jaw to base of last anal-fin ray, straight to slightly concave on caudal peduncle; snout slightly pointed, smaller than eye-diameter; mouth supraterminal, slightly oblique in profile; jaws subequal, lower jaw longer than upper, posterior end of rictus at same level or slightly ventral to centre of eye; premaxilla and dentary with many irregularly distributed unicuspid, slightly curved teeth, larger teeth 60-70 µm at outer row of lower and upper jaws; orbit in anterior half of head; branchiostegal membrane projecting posteriorly from operculum; all fins soft-rayed; dorsal-fin origin anterior to anal-fin origin, both fins originating posterior to mid-length of body; dorsal and anal fins rounded, with small contact organs in form of papillae on fin rays and distal margin with short filamentous rays; posterior extremity of dorsal fin reaching caudal-fin base; dorsal fin with 15-18 rays; anal fin with 15-18 rays; pectoral fin subtriangular, insertion at about vertical or slightly posterior to margin of opercular opening, base slightly oblique, upper fin rays placed slightly anteriorly to lower fin rays, tip reaching or slightly overlapping base of pelvic fin; pelvic fin subabdominal, origin at about mid-length of body, short, bases medially separated, tip reaching urogenital papilla; caudal fin subtruncate; scales cycloid, body and head entirely scaled, except for ventral surface of head; scales in mid-longitudinal series 26-30 plus 2 or 3 small scales on caudal-fin base; transverse rows of scales in front of dorsal-fin origin 10-11; scale rows around caudal peduncle 12; cephalic squamation pattern variable, some specimens presenting irregular E-type, with the pair of E-scales overlapping each other at the median lateral margin; anterior neuromasts separate in 2 grooves; cephalic sensory system at preorbital and supraorbital levels in shallow curved grooves, each with 1-2 neuromasts; one neuromast on each scale along trunk mid-longitudinal series (Ref. 97353).
Colouration: Live males: scales on trunk and head light blue with red-brown posterior margin, creating reticulated pattern on body and forming irregular cross bars; scales on abdomen faint light blue to silver; snout and dorsal portion of head red, throat white; exposed part of branchiostegal membrane orange; iris light blue, with faint black vertical bar through centre of eye; dorsal fin light blue with irregular red-brown stripes and spots, becoming narrower and denser towards distal edge of fin; anal fin light blue with elongated red-brown transverse spots proximally, followed by irregular stripes becoming denser distally, and with narrow light blue distal margin on fin tips; caudal fin light blue with irregular red-brown spots, more distinct at base, merging into striped pattern towards distal edge, parallel to fin rays, followed by a distinct light blue distal margin; pelvic fin light blue, with red-brown spots; pectoral fin yellow hyaline with light blue posterior distal margin (Ref. 97353). Live females: scales on trunk and head pale grey-brown, darker on back and lighter to silver on belly; dark grey reticulation on dorsal and posteroventral portions of flank; blue iridescence on trunk and opercular region; iris golden, with faint black vertical bar through centre of eye; all fins hyaline (Ref. 97353). |
| The type locality was a large ephemeral pool formed in a river bed, as a standing fragment of the seasonal river, at the collecting point about 100 m wide, and about 1.5 m deep at its deepest point; all collecting took place in the same general habitat; most parts of the habitat were heavily overgrown by grass and aquatic vegetation consisted of Nymphea species; water slightly turbid, whereas at shallower parts the bottom of the pool was visible; water temperature around noon 25.3°C, pH 7.30 and it contained 20 ppm of total dissolved solids (Ref. 97353). |
