| Diagnosis: |
Dorsal spines (total): 0-0; Dorsal soft rays (total): 15-16; Anal spines: 0-0; Anal soft rays: 16-18. Diagnosis: Nothobranchius angelae is distinguished from all other species of the genus by the following combination of characters in males: body colouration light blue to blue-green with red-brown or dark grey scale margins; anal fin light blue-grey to yellow-grey with irreguar brown spots, with narrow brown submedial band, slender white to pale cream medial band and broad black distal band; caudal fin light brown-grey with irregular dark brown spots proximally, followed by a narrow dark brown medial band, a slender white subdistal band and a slender to broad black distal band; pelvic fins light blue-grey to blue-green, with broad white to cream medial band and narrow black distal band (Ref. 122068). Furthermore, it differs from the other members of the Nothobranchius taeniopygus species group in central and western Tanzania by a postorbital length 55-63% of head length vs. 43-54%; and caudal peduncle length 132-137% of its depth vs. 119-130% and 140-169% (Ref. 122068).
Description: General body shape robust, laterally compressed and deep; greatest body depth at vertical in front of pelvic-fin origin, 30.7-34.7% of standard length; greatest body width at pectoral-fin base with body progressively narrowing towards caudal-fin base (Ref. 122068). 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; caudal peduncle relatively deep, length 1.32-1.37 times in its depth; anus situated directly in front of anal-fin origin (Ref. 122068). Head modestly long, 30.2-34.6% of standard length, laterally compressed, deeper than wide, head width 64-70% of its depth; 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 conical, slightly curved teeth at outer row of lower and upper jaws; orbit large, 24-31% of head length, entirely in anterior half of head, snout to eye end length 38-45% of head length, in dorsal portion of head side; branchiostegal membrane projecting posteriorly from opercle (Ref. 122068). Dorsal-fin origin anterior to anal-fin origin, both fins originating posterior to mid-length of body; extremity of 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 15-16 rays; anal fin 16-18 rays; pectoral fin subtriangular, insertion 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, with 19-21 branched rays, plus 2 or 3 dorsal and ventral procurrent rays (Ref. 122068). Scales cycloid, body and head entirely scaled, except for ventral surface of head; no scales on dorsal and anal fins; scales in mid-longitudinal series 27-30 plus two or three small scales on caudal-fin base; transverse rows of scales in front of dorsal-fin origin 11-12; scale rows around caudal peduncle 14 (Ref. 122068). Cephalic squamation pattern variable; frontal neuromasts separate in two rows of shallow grooves behind the upper lip, with one or two neuromasts in each groove; cephalic sensory system at supraorbital level in undivided shallow groove with five exposed neuromasts, whereas at supratemporal level with four exposed neuromasts in undivided, curved shallow groove; preorbital canal in shallow groove with four exposed neuromasts; infraorbital level with series of about 20 small buttons at ventral and posterior margin of orbit; postorbital canal in deep groove with one or two exposed neuromasts; preopercular system with exposed neuromasts in deep groove on preopercle portion, whereas with exposed neuromasts and small buttons on ventral portion; mandibular canal in shallow groove with about twelve small neuromasts; one neuromast on each scale along trunk mid-longitudinal series (Ref. 122068).
Colouration: Live male: scales on trunk and head light iridescent blue to blue-green with broad dark grey, red-brown of black margins, forming a regular reticulation pattern; scales on abdomen faint blue to cream with less pronounced margins; scales on the dorsum anterior to the dorsal fin with wider margins lending an overall darker appearance; snout, frontal and dorsal portions of head blue-grey to grey; throat pale blue to blue-green; exposed part of branchiostegal membrane white to cream; iris golden; dorsal fin light blue-green, blue-grey or yellow-brown with irregular brown to red-brown or dark grey spots in the basal and proximal zones, grading to streaks parallel to fin rays in the medial and distal zones, becoming finer distally; anal fin with broad light blue-grey to yellow-grey basal and proximal zones overlaid by irregular brown spots and, in at least one population, very dark grey overlaid by irregular white markings; proximal zone followed by a narrow, irregular, dark grey to brown submedial band, a medial zone comprising a white band, very rarely pale yellow in part, that may be slightly wider anteriorly than posteriorly, followed by a broad black distal band; basal and proximal zones of caudal fin light grey to grey-brown, or very dark grey, to black in one population, with darker brown to red-brown spots that may be elongate and aligned parallel to the fin rays; the arcuate pattern in the posterior part of the fin comprising a narrow, dark brown to black medial band, followed by a white subdistal band and a moderately broad black distal band; in at least one population the white band may form an incomplete arc, ending short of the upper edge of the fin; pelvic fins mimic, in part, pattern of anal fin with a light blue-grey to blue-green basal zone, followed by a broad white to cream medial zone and narrow black distal band; a blue subdistal band may be present in some populations; pectoral fins dominantly hyaline with prominent light blue or blue-green margins (Ref. 122068). Live female: trunk and head light grey-brown, darker on dorsum and lighter ventrally; scales with a very narrow grey margin; scale centres iridescent silver to very pale blue; all fins hyaline; iris golden (Ref. 122068). |