The honeycomb grouper (''Epinephelus merra''), also known as black-spotted rock-cod, common birdwire rockcod, dwarf spotted rockcod, dwarf-spotted grouper, honeycomb cod, wire-netted reefcod or wire-netting cod, is a species of marine

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fishes, is a class of bony fish. They comprise over 50% of living vertebrate species. The ray-finned fishes are so called because their fins are webs of skin supported by bony or hor ...

, a

grouper Groupers are fish of any of a number of genera in the subfamily Epinephelinae of the family Serranidae, in the order Perciformes. Not all serranids are called "groupers"; the family also includes the sea basses. The common name "grouper" is u ...

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 Groupers are fish of any of a number of genera in the subfamily Epinephelinae of the family Serranidae, in the order Perciformes. Not all serranids are called "groupers"; the family also includes the sea basses. The common name "grouper" is u ...

which is part of the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Serranidae The Serranidae are a large family of fishes belonging to the order Perciformes. The family contains about 450 species in 65 genera, including the sea basses and the groupers (subfamily Epinephelinae). Although many species are small, in some case ...

, 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 has a wide

Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...

distribution where it is found in coastal and offshore reefs in shallow waters.

Distribution

The Honeycomb grouper is one of the most common small groupers of the

. It is widespread throughout the

tropical The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in the Southern Hemisphere at S. The tropics are also referred to ...

waters of the

from South Africa to Pitcairn, north to southern Japan, south to Lord Howe Island. A single specimen was reported from french Mediterranean waters in 2005. It is not present in the

Red Sea The Red Sea ( ar, البحر الأحمر - بحر القلزم, translit=Modern: al-Baḥr al-ʾAḥmar, Medieval: Baḥr al-Qulzum; or ; Coptic: ⲫⲓⲟⲙ ⲛ̀ϩⲁϩ ''Phiom Enhah'' or ⲫⲓⲟⲙ ⲛ̀ϣⲁⲣⲓ ''Phiom ǹšari''; T ...

, the

Persian gulf The Persian Gulf ( fa, خلیج فارس, translit=xalij-e fârs, lit=Gulf of Persis, Fars, ), sometimes called the ( ar, اَلْخَلِيْجُ ٱلْعَرَبِيُّ, Al-Khalīj al-ˁArabī), is a Mediterranean sea (oceanography), me ...

, coastal India and Hawaii.

Description

''Epinephelus merra'' reaches a maximum known length of and it is one of the smaller fish species in the genus ''Epinephelus''.Allen, G.R. and M.V. Erdmann, 2012. Reef fishes of the East Indies. Perth, Australia: University of Hawai'i Press, Volumes I-III. Tropical Reef Research. This species has a long dorsal fin with eleven spines, 15-17 dorsal soft rays and 8 anal soft rays. The body is ochre to light brown, stocky, with an oval profile. It is covered by small brown hexagons with pale interspaces disposed on irregular darker diagonal bands and forming a network (hence the common name of the species). These hexagonal spots are also present on all fins. The caudal fin is rounded and the interorbital area is flat, with a convex dorsal head profile. The eyes are globular, with red-brown to black pupils. The lower jaw is longer than the upper one and on the midlateral part of the lower jaw there are 2-4 rows of teeth.

Biology

These solitary groupers live in seaward reefs and in shallow lagoon, usually at depths less than 20 m., but they can reach about 50 m. Juveniles prefer reefs with staghorn corals (

Acropora ''Acropora'' is a genus of small polyp stony coral in the phylum Cnidaria. Some of its species are known as table coral, elkhorn coral, and staghorn coral. Over 149 species are described. ''Acropora'' species are some of the major reef corals r ...

species). They mainly feed on fishes, crabs, shrimps and cephalopods, with and increase of piscivory with age. After the sexual maturity they are initially females and later they turn into males. Usually the groupers with a length of 16 cm are still females. These fishes usually spawn from January to April and the spawning begin 2 to 3 days before full moon and last about 3–4 days.

Hermaphroditism

The genus ''

Epinephelus ''Epinephelus'' is a genus of marine ray-finned fish, groupers from the subfamily Epinephelinae, part of the family Serranidae, which also includes the anthias and sea basses. They are predatory fish, largely associated with reefs and are found i ...

'' has the ability to change sexes, more specifically they are

protogynous hermaphrodites Sequential hermaphroditism (called dichogamy in botany) is a type of hermaphroditism that occurs in many fish, gastropods, and plants. Sequential hermaphroditism occurs when the individual changes its sex at some point in its life. In particular, ...

what means females can turn into males at one point in their life. This sex change usually happens in the non breeding season and can be caused by social stimuli, age, growth, and body size. Yet, the initial trigger for the sex change remains unknown.Bhandari Ramji Kumar,"Evidence That Estrogen Regulates the Sex Change of Honeycomb Grouper (Epinephelus merra), a Protogynous Hermaphrodite Fish", Journal of Experimental Zoology, vol.303A,2005 Females turn into males when they reach a length of approximately 20 cm, thus the size advantage model for sequential hermaphroditism applies in the case of the honeycomb grouper. The size advantage model states that if an individual can reproduce more effectively as one sex when small or young and as the other sex when larger or older, it should change sex at some point in its life history.

Taxonomy

The honeycomb grouper was first formally described in 1793 by the

German German(s) may refer to: * Germany (of or related to) **Germania (historical use) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizens of Germany, see also German nationality law **Ger ...

naturalist

Marcus Elieser Bloch Marcus Elieser Bloch (1723–1799) was a German physician and naturalist who is best known for his contribution to ichthyology through his multi-volume catalog of plates illustrating the fishes of the world. Brought up in a Hebrew-speaking Jewish ...

(1723–1799) with the type locality given as "Japan Sea" which is thought to probably mean the Indian Ocean. This species is one of a group of related members of the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

'' known as "reticulated coral groupers" along with '' E. bilobatus'', '' E. faveatus'', '' E. hexagonatus'', '' E. macrospilos'', '' E. maculatus'', '' E. melanostigma'', '' E. quoyanus'' and '' E. spilotoceps''. These species have frequently been mistaken for each other and as a result many specimens in museums have been misidentified.

References

External links

Sous le mer

Filmati di mare
* {{Taxonbar, from=Q1514631 Fish described in 1793 Fish of Palau

Honeycomb grouper The honeycomb grouper (''Epinephelus merra''), also known as black-spotted rock-cod, common birdwire rockcod, dwarf spotted rockcod, dwarf-spotted grouper, honeycomb cod, wire-netted reefcod or wire-netting cod, is a species of marine ray-finned ...