The giant grouper (Epinephelus lanceolatus), also known as the Queensland groper (grouper), brindle grouper or mottled-brown sea bass, is a species of marine ray-finned fish, a grouper from the subfamily Epinephelinae which is part of the family Serranidae, which also includes the anthias and sea basses. It has a wide Indo-Pacific distribution and is one of the largest extant species of bony fish.

Description

thumb|left|Juvenile coloration

The giant grouper has a robust body which has a standard length equivalent to 2.4 to 3.4 times its depth. The dorsal profile of the head and the intraorbital area are convex. The preopercle has a rounded corner and a finely serrated margin. The gill cover has a convex upper margin. There are 11 spines and 14–16 soft rays in the dorsal fin while the anal fin has 3 spines and 8 soft rays. The giant grouper can grow to huge size with the maximum recorded standard length being , although they are more common around , and a maximum published weight of . It occurs from the Red Sea and the eastern coasts of Africa as far south as Algoa Bay in South Africa and across the Indian Ocean into the Western Pacific Ocean as far east as the Pitcairn Islands and Hawaii. They occur as far north as southern Japan and as far south as Australia. Fish which inhabit coral reefs and rocky areas favour spiny lobsters as prey; a specimen taken off Maui in Hawaii had a stomach content of two spiny lobsters and a number of crabs. Fish living in estuarine environments in South Africa were found to be feeding almost exclusively on the crab Scylla serrata.

Reproduction

Like most groupers, giant groupers are protogynous hermaphrodites. They spawn on a lunar cycle, with spawns lasting about 7 days. They are aggregative broadcast spawners, usually with several females per male. Studies in captive populations suggest that the dominant male and female begin the spawning event as nearly the only spawners for the first day or two, but other members of the aggregation fertilize more eggs as the event progresses, with even the most recently turned males fathering offspring. Giant groupers are diandric protogynous hermaphrodites, meaning that although some males develop from reproductively functional females other males start to produce sperm without ever having gone through a phase as a reproductive female.

Taxonomy

The giant grouper was first formally described as Holocentras lanceolatus in 1790 by the German medical doctor and naturalist Marcus Elieser Bloch (1723–1799) with the type locality given as the East Indies. Felipe Poey assigned the giant and goliath groupers (Epinephelus itajara and E. quinquefasciatus, which was then regarded as a synonym of E. itajara) to the genus Promicrops but in 1972 this was designated as a subgenus of Epinephelus. However, these species are still each other's closest relatives.

References

  • Epinephelus lanceolatus on the Integrated Taxonomic Information System
  • Queensland Groper, Epinephelus lanceolatus from the Australian Museum