Yellow-Axil Chromis

Chromis xanthochira

The Yellow-axil chromis is a small reef fish belonging to the family Pomacentridae. It can reach a maximum length of 14 cm and is characterized by a compressed body shape. Divers can identify this species by its distinctive dorsal fin structure, which includes 13 spines and 11 soft rays, and an anal fin with 2 spines and 11-12 soft rays. This fish is typically found in tropical marine environments, particularly along the deep outer reef walls of the Western Central Pacific. Its distribution includes regions such as Indonesia, the Philippines, Palau, Guam, Papua New Guinea, the Solomon Islands, and the northern Great Barrier Reef, with occasional reports from Christmas Island in the eastern Indian Ocean. The Yellow-axil chromis inhabits depths ranging from 10 to 48 meters, although most occurrences are shallower than 40 meters. It is primarily a diurnal species, active during the day, and feeds on plankton. This fish is often seen alone or in small groups on outer reef slopes, where it engages in distinct pairing during breeding. Reproduction involves oviparous behavior, with males taking responsibility for guarding and aerating the demersal eggs that adhere to the substrate. Divers encountering the Yellow-axil chromis can expect to find it in small groups or solitary along reef walls, feeding on plankton. The species is listed as Least Concern by the IUCN.