Species Details

Details of Dusky farmerfish will be displayed below

Dusky farmerfish   

Common Name: Dusky Damselfish, Dusky Farmerfish, Mamo
Scientific Name: Stegastes nigricans
Local Name: -
Dhivehi Name: -
Animalia  (Kingdom)
Chordata  (Plylum)
Teleostei  (Class)
Perciformes  (Order)
Pomacentridae  (Family)
Stegastes   (Genus)

Dusky farmerfish's description

The dusky farmerfish (Stegastes nigricans) is a species of damselfish found around coral reefs at a depth of one to 12 meters, in tropical climates between 30°S and 30°N. They are known for farming monocultures of algae such as cyanophores and rhodophytes.

Short description - Dorsal spines (total): 12; Dorsal soft rays (total): 15-17; Anal spines: 2; Anal soft rays: 12 - 14. Diagnosis: Adults generally brown; dorsal part of head and nape darker, grading to tan on lower part of head and breast. The scales have darker brown margins. The lips are whitish lips; the suborbital is mostly blue; the preopercle and opercle scales with blue centers. The median and pelvic fins are brown; the pectorals are dusky; a well-defined dark brown or blackish spot is sometimes present at base of posteriormost dorsal rays, which distinguishes it from S. lividus where the spot is diffuse. Males in courtship or guarding eggs with broad white bar across middle of body and pale blue stripe from mouth to upper part of pectoral fin.

Max length - 14.0 cm TL male/unsexed; common length : 9.0 cm TL male/unsexed.

Dusky farmerfish's Behavior & Ecology

Adults inhabit reef flats and lagoon reefs. Frequently occur in colonies associated with live or dead branching staghorn coral (Acropora). Feed on algae, gastropods, sponges, and copepods. Territorial, maintain and 'weed' filamentous algae patches growing on dead coral. Particularly aggressive during reproductive periods. The species emit clicking noises during aggressive encounters. Oviparous, males tend the nest visited by several females.

Dusky farmerfish's Reproduction

Oviparous, distinct pairing during breeding. Eggs are demersal and adhere to the substrate. Males guard and aerate the eggs.

Dusky farmerfish habitat

This species occurs around dead branching corals often in groups that are aggressive towards divers and other algae-eating fishes (Randall 2005, Allen and Erdmann 2012). Habitat association has been observed between this species and various branching corals, including Porites rus, P. cylindrica, Acropora pulcra, and other species from the genus Acropora (Myers 1999, Lecchini and Galzin 2005, Randall 2005, Johnson et al. 2011, Coker et al. 2014). The maximum total length is 14 cm (Allen and Erdmann 2012).

Dusky farmerfish threats

There are no known major threats.

Dusky farmerfish's status