Chrysiptera hemicyanea

Lore & Background

The generic name Chrysiptera combines the Greek words chrysos ('golden') and pteron ('fin' or 'wing'), while the specific name hemicyanea means 'half blue,' referring to the blue head and upper body. This tropical marine fish reaches 7 cm in length and is mostly bright blue with a bright yellow bottom; different species in the genus have varied amounts of gold coloring.

It is native to the eastern Indian Ocean and western Pacific, with greatest populations in the Coral Triangle (from the Solomon Islands to Indonesia, Bali, and the Philippines). It has also recently been filmed in the Mediterranean Sea off Malta. Typically found in waters 1 to 38 m deep, it is non-migratory and inhabits lagoons or near-shore reefs, often around rock structures or branching corals like Acropora. It is a reef-dependent species that needs corals or other structures for protection from predators, and primarily eats plankton and small invertebrates.

Reproduction in the genus Chrysiptera involves mating pairs, benthic egg-laying where eggs are adhered to a substrate, and a male that guards and aerates the eggs. The larval stage is shorter than in other damselfish, which causes issues with distribution. The population has the ability to double in 15 months.

Reader's Guide

Chrysiptera hemicyanea is a popular species in the home aquarium, along with closely related species like Chrysiptera talboti and C. rollandi. In captivity it is considered hardy and easy to care for, tolerating minor changes in water chemistry, and is recommended for beginners in the saltwater aquarium trade. It will eat just about anything, including fish flakes and frozen brine shrimp. Although it is considered a schooling fish (especially around SPS corals), it is quite aggressive and territorial; fish that invade its area are harassed, sometimes to death. The best way to avoid this is to place the fish in a large enough tank with plenty of structure like coral or live rock. Recently, this species has been successfully bred in captivity to increase supply to the aquarium trade and decrease environmental impact.

Conservation of this species primarily involves maintaining its coral reef habitat. Coral reefs are disappearing in most areas due to coral bleaching, caused by warmer average temperatures that overheat and kill corals, turning them white. Global warming is thought to be the primary cause of reef destruction and is projected to cause severe damage to global coral reefs by the middle of the century. As coral reefs die out, it may become necessary to supplement structure with artificial reefs or any type of structure that fish can hide in.