Habitat:Reef-associated, demersal, hiding in crevices or under ledges during the day. These shallow water nocturnal fish occur from the surface down to a maximum depth of 100 m. Most species live in aggregations as young, becoming solitary as adults.
Morphology:
Squirrelfishes and Soldierfishes are usually reddish in color with large, rough, ctenoid scales. The dorsal fin is long, with a notch between the spiny and soft rays, and the caudal fin is usually forked. They have a single spine in each of their pelvic fins and a spiny edge to their operculum. They have large eyes.
(Fishbase ID Key) Some members of this Family reach 61 cm maximum length.
Remarks:
Squirrelfishes and Soldierfishes are usually reddish in color with large, rough, ctenoid scales. The dorsal fin is long, with a notch between the spiny and soft rays, and the caudal fin is usually forked. Most species are nocturnal. The family name, Holocentridae, comes from the Greek holos, meaning "whole" and kentron, meaning "sharp point." This refers to the spiny edge of the opercle, and in many cases, the strong, sometimes toxic, preopercular spine.
These fishes have large eyes and are usually nocturnal. They hide under ledges of the reef during the day, and remain close the bottom during the night.
The Holocentrid Squirrelfishes have the strong spine at the angle of the preoperculum, and the longest dorsal spine is usually shorter than the longest anal spine. They have tubular swim bladders which run the entire length of the body and they feed on small fishes and benthic invertebrates. In contrast, the Myopristin Soldierfishes have no enlarged preopercular spine, their longest dorsal spine is longer than their longest anal spine, and their swim bladder resides in the last third of the body and forms two separate chambers. Soldierfishes eat large zooplankton.
These fishes achieve a maximum length of 61 cm, and are important foodfishes. Some species are also kept in home marine aquariums.
This family includes eight genera, and about 78 species. There are two subfamilies, Holocentrinae (Squirrelfishes) and Myripristinae (Soldierfishes).
References:
Nelson 2006