African blackspot threadfin (Polydactylus malagasyensis)

Scientific name: Polydactylus malagasyensis Motomura & Iwatsuki, 2001

The African blackspot threadfin (Polydactylus malagasyensis) is a brackish-water fish of the family Polynemidae. Native range: Western Indian Ocean, Kenya, Mozambique, South Africa, and Madagascar. Likely to occur in Somalia and Tanzania.

Biology

Dorsal spines (total): 9; Dorsal soft rays (total): 12-13; Anal spines: 3; Anal soft rays: 12; Vertebrae: 24. With 6 pectoral filaments; uppermost not reaching to (or extending slightly beyond) posterior tip of pectoral fin. Pectoral fin, rays long, 21-26% of SL; fin base long, 10-12% of SL; all rays branched except uppermost 1 or 2. Second dorsal spine long, 7-9% of SL. Well-developed swim bladder. A large black spot anteriorly on lateral line.

Source: FishBase, licensed CC BY-NC 4.0.

Species facts

Scientific name: Polydactylus malagasyensis
Family: Polynemidae (Threadfins)
Order: Perciformes (Perch-like fish)
Class: Actinopterygii (Ray-finned fishes)
Maximum length: 14.9
Depth range: 5–62 m (16–203 ft)
Environment: Marine; brackish; demersal; depth range 5 - 62 m
Climate: Tropical
Distribution: Western Indian Ocean: Kenya, Mozambique, South Africa, and Madagascar. Likely to occur in Somalia and Tanzania.
Conservation status (IUCN): Not Evaluated
Threat to humans: Harmless
Uses: Fisheries: of no interest
Resilience: High, minimum population doubling time less than 15 months (Preliminary K or Fecundity.)

Sources

Taxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.

Last updated 27 September 2026