Epinephelus fasciatus

The blacktip grouper or redbanded grouper, Epinephelus fasciatus, is a species of marine fish in the family Serranidae. The blacktip grouper is widespread throughout the tropical waters of the Indo-Pacific area from the Red Sea to South Africa, as far north as Korea, and in the waters around Australia to Pitcairn Islands. It is also commonly found around the Mascarene Islands and is a prized commercial fish in Mauritius. The blacktip grouper grows up to 40 cm in length and may weigh up to 2 kg, but its common size is average 22 cm. These fishes have eleven dorsal spines, 15-17 dorsal soft rays, three anal spines and eight anal soft rays. The tips of the spines of the dorsal fin are black. The caudal fin is rounded. They are quite changeable in their color, ranging from pale greenish grey to pale reddish yellow or pinkish. Their body shows 5-6 dark transversal stripes. The top of head is reddish brown, usually with paler markings. They may have a dark red cap above the eyes, as well as a narrow black edge around the eyes. A variant occurs with a uniformly pale body except for the front part. This species may present simultaneous hermaphroditism in smaller individuals, while the large individuals usually lose female function. The blacktip grouper feeds on crustaceans and smaller fishes by ambushing them. It is found associated with coral reefs from 4 m deep (more commonly from 15 m) up to 160 m, in both marine and brackish water, sometimes in groups of 10-15 individuals. Juveniles may find shelter in mangrove swamps. Blacktip groupers of the Red Sea are fished by the Bedouin. It has also been associated with ciguatera poisoning. Blacktip groupers are host of several parasites, including Pseudorhabdosynochus spp. (diplectanid Monogeneans) on the gills. The philometrid nematode Philometra fasciati is parasitic in the ovary of female fish; the adult female parasite is a red worm which can reach up to 40 centimetres in length, for a diameter of only 1.6 millimetre; the males are tiny.