Croilia mossambica Smith, 1955
Burrowing goby
Croilia mossambica
photo by SFSA

Family:  Gobiidae (Gobies), subfamily: Gobiinae
Max. size:  6.4 cm TL (male/unsexed)
Environment:  demersal; freshwater; brackish; marine; depth range 1 - 16 m, amphidromous
Distribution:  Africa: coastal lakes and estuaries in KwaZulu-Natal, South Africa, and southern Mozambique (Ref. 2798, 52193); also recorded from Madagascar (Ref. 4343).
Diagnosis:  Dorsal spines (total): 6-6; Dorsal soft rays (total): 11-12; Anal spines: 0-0; Anal soft rays: 12-12. Description: Head and body compressed and elongated; snout steeply sloping; eyes large and projecting (Ref. 52193). Dorsal fin with 6 spines and 11-12 soft rays; anal fin with 12 soft rays; dorsal fin separated or partly connected by membrane; caudal fin pointed (Ref. 2798, 52193). Scales absent (Ref. 52193).

Colouration: Translucent, with brown spots on dorsal fin and head; caudal fin of males with vertical bars, females with a single horizontal bar on the lower edge (Ref. 52193). Dark bar under eye; tan in colour, with dark spots above; sides with 6-10 vertical bars; large specimens with black margined dorsal and anal fins (Ref. 2798).

Biology:  Lives in burrows excavated in clean sand, often in association with the sandprawn Callianassa kraussi (Ref. 52193). Restricted to sandy, quiet water areas and is unable to form burrows where the substrate is disturbed by water movements, is muddy or consists of sand with a particle diameter > 0.5 mm (Ref. 28077). Food consists of slow moving benthic organisms like chironomid larvae, gastropods, bivalves and amphipods (Ref. 28077). Breeds throughout summer, males are territorial (Ref. 52193). On exposed shores, they occur deeper than 3.5 m (Ref. 28077, 2798). Occasionally intertidal.
IUCN Red List Status: Least Concern (LC); Date assessed: 01 March 2007 Ref. (130435)
Threat to humans:  harmless


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 Not for publication.