Ostorhinchus compressus, commonly called the ochre-striped cardinalfish, blue-eyed cardinalfish or split banded cardinalfish, is a marinecardinalfish from the Indo-West Pacific from the familyApogonidae. It occasionally makes its way into the aquarium trade. It grows to a size of 12 cm in length.
The genusAmia initially allocated by the authors subsequently proved to be a synonym of Ostorhinchus, making its way via Apogon.[4]
Description
Although the maximum recorded standard length of O. compressus is 12 cm, its most common adult length is around 8.5 cm. Adults are pinkish-white, with six brown stripes along each side, iridescent blue eye rings, and up to four brown spots on the caudal peduncle (tail base). Juveniles begin with a black spot on a yellow caudal peduncle, which appears to mimic juveniles of certain piscivorous species of Cheilodipterus.[5]
Meristics
Using a shorthand meristics formula, O. compressus can be described as having:
Research on the larval stage of this species shows that as it develops, its ability to see in ultraviolet light increases. Given that the larval stage is pelagic, this implies that older larvae can migrate down the water column to feed.[8] This might improve its predator evasion, whilst improving its food intake.
Settlement
Generally found from 2–20 metres, adults rest during the daytime in floating mixed species groups with other Apogonids. They are not very picky, being found resting in association with several kinds of live hard coral, Gorgonians, dead coral, rubble, and sand.[9] Possibly because of the low water circulation, higher temperatures, and high oxygen consumption of some of the shallow branching corals into which O. compressus retreats from predators, it has been found to tolerate very low dissolved levels of oxygen, even at a temperature of 30 °C (which is likely to stimulate a relatively high resting metabolic rate).[10]
Parasites
The gills of O. compressus have been found infected with Gyrodactylid flatworms.[11]
^Nilsson, G. E. & Ostlund-Nilsson, S. (2006). "Hypoxia tolerance in coral reef fishes". In Val, A. L.; Almeida-Val, V. M. F. & D. J. Randall (eds.). The Physiology of Tropical Fishes. Elsevier. pp. 583–596. ISBN9780123504456.