Kyphosus ocyurus

Content sourced from Wikipedia, licensed under CC BY-SA 3.0.

Kyphosus ocyurus, the blue-striped chub or rainbow chub, is a marine fish in the sea chub family Kyphosidae. It lives in the tropical eastern Pacific, from the Galapagos to Hawaii, and along the American coast from Southern California to Peru, including various Pacific islands such as Guam, Palau, Marquesas, and the Izu Islands.

Appearance
It has an elongated, oval body with a convex head and a short mouth. The back is metallic blue and the belly white, with two wavy horizontal stripes running from the mouth to the tail—one yellow and one bluish. The head can be yellow to silvery with a blue streak behind the eye. It grows up to about 59 cm (23 in), though most are around 25 cm (10 in). The tail is deeply forked. The dorsal fin has 11 spines and 13 soft rays; the anal fin has 3 spines and 14 soft rays.

Habitat and behavior
It prefers rocky, clear-water habitats near the surface down to about 25 m. Juveniles often live among submerged vegetation, but adults spend more time in open water near reefs and hard bottoms. They can be solitary or form small to moderate mixed schools with other Kyphosus species and are sometimes seen swimming quickly in open water near reefs or drop-offs. They’re also occasionally found near floating logs far out to sea.

Diet
K. ocyurus is more omnivorous than other Kyphosus species, feeding on zooplankton as well as algae and other small organisms.

Reproduction and life cycle
Juveniles use submerged vegetation as a nursery before moving to open water as they grow.

Taxonomy
The species was first described in 1882 as Pimelepterus ocyurus. It has been placed in other genera in the past, but genetic data place it in Kyphosus, where it is closely related to K. vaigiensis.