Hemichromis angolensis Steindachner, 1865 |
Family: | Cichlidae (Cichlids), subfamily: Pseudocrenilabrinae | |||
Max. size: | 10.93 cm SL (male/unsexed) | |||
Environment: | benthopelagic; freshwater | |||
Distribution: | Africa: Cuanza River in Angola (Ref. 120641, 123791, 128620),; also in Zambezi River and Okavango system (Ref. 128620).. | |||
Diagnosis: |
Dorsal spines (total): 13-15; Dorsal soft rays (total): 10-12; Anal spines: 3-3; Anal soft rays: 9-11. Diagnosis: Hemichromis angolensis can be distinguished from H. fasciatus by the absence of small black dots between the first three dark stripes on the flanks of the body of adults in most populations of H. fasciatus; it can further be distinguished from H. fasciatus by a combination of overlapping morphometrics, mainly by a high number of anal fin soft rays, 9-11 vs. 8-10; a greater body depth, 30.3-42.4% of standard length vs. 27.1-37.8%; a greater head depth, 51.4-70.6% of head length vs. 48.4-66.0%; and shorter length of lower jaw, 35.4-45.7% of head length vs. 40.0-49.0% (Ref. 128620). Hemichromis angolensis can be distinguished from H. camerounensis by a combination of overlapping morphometrics, mainly by a greater prepelvic distance, 39.0-52.0% of standard length vs. 37.6-48.5%; a shorter length of anal fin base, 13.2-17.7% of standard length vs. 14.5-18.3%; and greater preorbital distance, 10.3-18.1% of head length vs. 9.1-13.2% (Ref. 128620). Hemichromis angolensis can be distinguished from H. elongatus by a combination of overlapping morphometrics, mainly by a shorter head length, 33.6-39.7% of standard length vs. 36.9-40.2%; a shorter length of anal fin base, 13.2-17.7% of standard length vs. 14.8-22.8%; greater eye orbit diameter, 19.8-31.0% of head length vs. 18.8-28.8%; and shorter length of lower jaw, 35.4-45.7% of head length vs. 38.9-46.2% (Ref. 128620). Description: General body shape deep and moderately elongated; dorsal and anal fins reaching or exceeding level of caudal fin origin; dorsal fin straight with a high number of soft rays, soft rays 5 to 6 longest; length of pectoral and pelvic fin rays decreasing from first to last branched rays; caudal fin moderately truncate or rounded; caudal peduncle from deeper than long to longer than deep (Ref. 128620). Head short, with straight to slightly profile, mouth sub-isognathous to prognathous; snout relatively long, eyes of intermediate size, cheek with high number of scale rows in most specimens; upper jaw with two rows of teeth, lower jaw with one row; infraorbital series containing a lachrymal with four openings of the laterosensory system and five additional tubular bones; premaxilla with two, dentary with one row of regularly set unicuspid teeth; six to eight gill rakers on ceratobranchials of first outer gill arch, and three to five gill rakers on upper parts (Ref. 128620). Scales cycloid; three or five rows of scales on cheek; four horizontal rows on opercle; dark spot on outer edge of opercle without scales; chest-scales mostly smaller than body scales, four or five scales between pectoral and pelvic fins; upper lateral line separated from dorsal fin base anteriorly by three and a half to four and a half scales, at the 8th pored scale by two and a half or three scales, and at last pored scale by one and a half or two scales; end of upper lateral line rarely overlapping lower lateral line or distanced by no scale, more often separated from beginning of lower lateral line by one to five rows of scales; about 1/4 of caudal fin covered with scales, and all other fins unscaled; total lateral-line scales 27-31, upper lateral-line scales 16-19, lower lateral-line scales 6-13; circumpeduncular scales 16 (Ref. 128620). Dorsal fin with 13-15 spines and 10-12 rays; anal fin with 3 spines and 9-11 rays; pectoral fin with 12-14 rays (Ref. 128620). Total gill rakers 10-13, gill rakers on lower limb of first arch 6-8 (Ref. 128620). Colouration: Colour of living specimens: no sex-specific colouration differences visible; general colour pattern silvery-grey to pale yellow or greenish, with generally five large vertical dark stripes; scales on flanks of semiadult and adult specimens marked at edges by silvery, pink, or red colour with a yellow or golden center, producing a pattern of alternating horizontal silver/red and yellowish/golden lines on the flanks; in adult and possibly dominant specimens, the red lines on lower flank parts may broaden and form a uniform coloured red belly part which may extend to lower parts of head; operculum often with two red spots flanking opposite sides of large black opercular spot, upper spot, or sometimes both red spots may disappear in specimens, possibly depending on behavioral situation or dominant status; dorsum dark greyish; dark lachrymal stripe extending over iris and above eye; fins pale yellowish or whitish in semiadult specimens; in adults dorsal, caudal and anal fins dark grey to blackish, dorsal fin and most upper edge of caudal fin often with thin red margin, pectoral fins with pale yellowish to pale greyish colouration; outer edge of pelvic fins black, most proximate parts of these fins paler to yellowish; smallest juveniles, for the first weeks of life, with pale yellow body colour and one prominent horizontal black band on body, extending from head to end of caudal peduncle (Ref. 128620). Colouration of preserved specimens: general body colour yellowish-brown with five large dark blotches or stripes on the flanks, less visible in old material; large black opercular spot; longitudinal pattern of brown and yellow alternating lines can be visible in some specimens (Ref. 128620). |
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Biology: | ||||
IUCN Red List Status: | Not Evaluated (N.E.) Ref. (130435) | |||
Threat to humans: | harmless |