Goldtail Damselfish Chrysiptera parasema

The front part of the Goldtail Damselfish, also called Yellowtail Blue, including most or all of the body, is blue, but varies from pale blue when the fish is relaxed to purple or even dark blue when it is stressed. The yellow or gold at the rear can be just the tail portion or can include rear fins and a small part of the rear body. There may also be yellow on front fins but never on the belly or head.

It grows to 7-8cm long. It is native to tropical reefs of the western Pacific, mainly Indonesia, the Phippines and Papua New Guinea. A male will prepare a nest site and females will choose in which male's nest to lay; the male will then aggressively guard the eggs until they hatch. (Another fish is also called the Yellowtail Damsel, the Atlantic Jewel Damsel, Microspathodon chrysurus.)