The sailfin grouper (''Mycteroperca olfax''), also known as the bacalao grouper, colorado grouper or yellow grouper, is a species of marine ray-finned fish, a grouper from the

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end subfamily botanical names with "-oideae", and zoologi ...

Epinephelinae which is part of the family Serranidae, which also includes the

anthias Anthias are members of the family Serranidae and make up the subfamily Anthiinae. Anthias make up a sizeable portion of the population of pink, orange, and yellow reef fishes seen swarming in most coral reef photography and film. The name Anthi ...

and sea basses. It is found off islands in the eastern Pacific.

Description

The sailfin grouper has a body which is elongate, robust and compressed with its depth being the same at the origin of the dorsal fin as it is at the origin of the

anal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

. The

standard length Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish m ...

is 2.9 to 3.1 times the body's depth. The preopercle is angular, with a serrated lobe at its angle. The dorsal fin contains 11 spines and 16-17 soft rays while the

contains 3 spines and 11 soft rays. The membranes between the dorsal fin spines are not deeply notched and the soft rayed part of the dorsal fin is rounded. The caudal fin is emarginate in adults and truncate in juveniles. The head and body are normally pale grey-brown in colour with numerous, closely set brown spots and they sometimes have 10-12 thin dark bars, which may be broken, on the upper body. The fin margins are dark, with narrow white borders. Occasionally they are entirely bright yellow in colour. This species attains a total length of .

Distribution

The sailfin grouper is found in the eastern Pacific Ocean where it occurs in the waters off the Galapagos Islands of Ecuador, Cocos Island in Costa Rica and Malpelo Island of Colombia. Vagrants have been recorded sporadically along the coast between Costa Rica and Peru.

Habitat and biology

The sailfin grouper occurs along rock walls, over rocky reef drop-offs, underwater lava ridges and around other vertical rock formations as adults, the juveniles have been recorded from shallow sandy lagoons, sea grass beds, mangrove lagoons, shallow lava reefs and even inland lava ponds. The adults are piscivorous and the main prey of the larger adults is the pacific creolefish (''

Paranthias colonus ''Paranthias colonus'' (the Pacific creolefish) is a species of grouper found in the Eastern Pacific Ocean. They are typically found in small aggregations well above reefs, but will retreat to the reef at the approach of danger. They form large m ...

''). The females become sexually mature at 4 years of age and with a total length of around . The transition to males takes place around 12 year of age and when the total length is . The skewed sex ratio and lack of small males suggests that this species is a monandric protogynous hermaphrodite but this has not been confirmed histologically. Spawning has been observed from October until April, peaking in October and December, and aggregations have been recorded. Outside the spawning season the malesa and females appear to be ecologically separated with the males further offshore than the females.

Taxonomy

The sailfin grouper was first formally described as ''Serranus olfax'' in 1843 by the English clergyman, author and naturalist Leonard Jenyns (1800-1893) with the type locality given as

San Cristóbal Island San Cristóbal Island ( es, Isla San Cristóbal) and named previously by the English as ''Chatham Island'', is the easternmost island in the Galápagos archipelago, as well as one of the oldest geologically. It is administratively part ...

in the Galapagos. In 1862 the

American American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, pe ...

zoologist Theodore Nicholas Gill (1837-1914) placed it in the monotypic genus '' Mycteroperca'', which has since been expanded to include 14 other species, and ''M. olfax'' is therefore its type species.

Utilisation

The sailfin grouper is the commonest and most valuable finfish landed in the Galápagos by the artisanal handline fishery and has been since the Norwegians introduced the butterfly method of salting and drying fish that gives bacalao (known as cod in Spanish) its name in the late 1920s. The dried flesh is exported to the mainland Ecuador where it is used in a traditional Easter dish called fanesca. The fishery operates throughout the year but it peaks from October until April when the demand is at its peak in the lead up to Easter. In 2008 it was reported that fishing effort was being reduced as fishers targeted the more valuable sea cucumber and lobster stocks. Sailfin groupers are also targeted by recreational game fishing tourists.

Sources

External links

* {{Taxonbar, from=Q2243106 sailfin grouper Endemic fauna of Ecuador Galápagos Islands coastal fauna Vulnerable animals Vulnerable biota of South America sailfin grouper Taxonomy articles created by Polbot