Peacock hind, Roi, Bluespotted grouper, Celestial grouper
Cephalopholis argus, the peacock hind, roi, bluespotted grouper, and celestial grouper, is a species of marine ray-finned fish, a member of the subfamily Epinephelinae, the groupers, and part of the family Serranidae, which also includes the anthias and sea basses. They come from the Indo-Pacific which is variously a commercial gamefish, an invasive species, and occasionally an aquarium resident. Its species name comes from its resemblance to the "hundred staring eyes" of the monster Argus who had a hundred eyes and was the shepherd of the goddess Hera in Greek mythology.
Ov
OviparousOviparous animals are female animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive...
No
Not a migrantAnimals that do not make seasonal movements and stay in their native home ranges all year round are called not migrants or residents.
C
starts withThis is a medium-sized fish that can reach a length of 60 centimeters (24 in). Small individuals are dark brown with hundreds of small, dark-edged iridescent blue spots. Larger specimens sometimes develop four to six lighter vertical bars on the back half of its body.
The species is extremely widely distributed, occurring in warm waters from the Red Sea to South Africa and east to French Polynesia and the Pitcairn group. It is also present in northern Australia, Lord Howe Island, and Japan, and has been introduced to the Hawaiian Islands. It makes use of a variety of habitats but prefers the exposed fronts of reefs, at depths of up to 40 m.
The species typically sit on a coral head, retreating when startled.
Red Sea males defend harems of 2–6 females in territories ranging up to.5 acres (0.20 ha). Each female defends part of the territory from the other females. The male visits each female daily, raising his dorsal fin to signal his approach. The females emerges from hiding, erecting her own dorsal fin and changing to a lighter color. They swim together, rubbing flanks before he departs until the next day.
Territorial disputes may involve "color fights" in which two males positioning themselves at right angles to each other. They then darken their color and repeatedly switch their bars from dark to light. The loser becomes pale and retreats. If the color fight ends in a draw, the two males may attack each other.
Hunting, they lie on the bottom and surge forward, preferring juvenile surgeonfish and crustaceans. Alternatively they may hover motionless in the water column before attacking.
This grouper may follow and cooperate with another predator species, such as an octopus or eel or camouflage themselves in a school of surgeonfish. Multiple individuals may cooperate to harass an eel to get it to flush prey for them.
In the Red Sea, they hunt in the morning and evening.
Analysis of stomach contents of Hawaiian roi found that diets consist of 97.7% fish and 2.3% crustaceans. Of the fish eaten, there were 27.1% Scaridae (Parrotfish), 18.7% Acanthuridae (Surgeonfish), 17.6% Squirrelfish, 13.7% Monacanthidae (Filefish), 9.3% Priacanthidae (Bigeyes), 4.3% Chaetodontidae (Butterflyfish), 2.8% Aulostomidae (Trumpetfishes), and 6.9% other consisting of 9 families. Roi are estimated to eat 0.8% of their body weight each day.
In Micronesia, spawning usually occurs territorially at dusk. During courtship, both sexes darken except for a white keyhole-shaped patch at the center of the body.
The species is classified as Least Concern by the IUCN. and is widespread and common throughout its range. It is exploited in commercial and recreational fisheries and for the aquarium trade.
Cephalopholis argus is a hardy aquarium fish for those who have a large marine aquarium. Its large size combined with its aggressive nature means it is best housed either alone or with other large aggressive fish such as lionfish, and moray eels. As a predator it will eat any smaller aquarium inhabitants such as damselfish.
