Acanthurus pyroferus is common at Kwajalein on seaward, lagoon and pinnacle reefs. The adults are typically brown with red behind and below the gills and a yellow margin to the tail fin. Juveniles mimic various species of pygmy angelfish. It is thought that the wary behavior of the angels, darting in and out of holes in the reef, makes them a poor target for many predators, and the juvenile tangs take advantage of this when they resemble them. When the tangs get too large to reasonably mimic pygmy angels, they change to their adult, rather drab colors.
Developing its darker adult color from a yellow juvenile.
Even younger than the one above, this one is still mostly yellow but the red behind the gills is beginning to appear.
This juvenile form is thought to mimic the pygmy angel Centropyge heraldi, which is at lower left in the first photo below.
Some juveniles develop a blue eye and margin, clearly mimicing Centropyge flavissima.
Centropyge vrolikii is a rare pygmy angel at Kwajalein, but some juvenile Acanthurus pyroferus will mimic it nonetheless.
Juvenile Acanthurus pyroferus will even mimic hybrids between Centropyge vrolikii and C. flavissima.
This adult had a patch of light color on one side.
Created 8 July 2017