Pearsonothuria graeffei is uncommon at Kwajalein and found in Halimeda patches on sandy lagoon reefs. This species changes considerably as it grows from a small juvenile that resembles some poisonous nudibranchs to its adult form. The first few photos show the adult coloration.
The next couple show more of an intermediate color between juvenile and adult.
Small juveniles are thought to resemble some species of poisonous phyllidiid nudibranchs, a form of mimicry that may help protect them from predation.
Created 21 June 2018
Updated 11 March 2019