Opsaridium tweddleorum Skelton, 1996
dwarf sanjika

Family:  Danionidae (Danios), subfamily: Chedrinae
Max. size:  11 cm SL (male/unsexed)
Environment:  demersal; freshwater
Distribution:  Africa: western affluent perennial rivers of Lake Malawi and tributaries of Shire River, lower Zambezi (Ref. 26673, 52193).
Diagnosis:  Dorsal spines (total): 0-0; Dorsal soft rays (total): 10-11; Anal spines: 0-0; Anal soft rays: 16-16. Description: Body fusiform (Ref. 52193). Head pointed, with large terminal mouth; lower jaw extends to below mid-orbit (Ref. 52193). Dorsal fin with 2 unbranched and 8-9 branched rays; anal fin with 3 unbranched and 13 branched rays; dorsal fin nearer base of caudal fin than tip of snout, dorsal fin origin behind pelvic fins, before anal fin; caudal fin forked; anal fin with anterior rays extended (Ref. 52193). Scales in lateral line 45-49, 16-17 around caudal peduncle; lateral line dips to lower half of body (Ref. 52193).

Colouration: Pale bluish grey with 11-13 darker upright bars along body; dorsal fin with a distinct black band arching from leading edge to lower hind corner (Ref. 52193). Males have prominent tubercles on head and fins (Ref. 52193).

Biology:  Found in swift-flowing streams in rocky reaches over clean sand (Ref. 52193).; prefers clear, fast flowing waters (Ref. 26673). It feeds on insects and other invertebrates in the drift (Ref. 52193). Breeds in summer (Ref. 52193).
IUCN Red List Status: Data deficient (DD); Date assessed: 21 May 2018 Ref. (130435)
Threat to humans:  harmless


Source and more info: www.fishbase.org. For personal, classroom, and other internal use only. Not for publication.