Metriaclima callainos

Description:

Distribution: On the Northwest coast at Kande Island to Ngara, Northeast coast from Ikombe to Puulu. 
"Cobalt" introduced in the south at Thumbi East Island to Maleri Island.

Habitat: Found in rocky habitats from 1-25 metres.

Diet: Algae.

Adult Size: Up to 14cm.

Appearence: There are three different colour morphs. 
The "Cobalt" occurs from Katale Island to Mbowe Island. Males are a very light brilliant blue, but pure white males have been observed at Mara Rocks and Cape Manulo. Females are also light blue but do not show the brilliance of the males. 
"Pearl" males appear white, but have a mother of pearl sheen. Females are a creamy colour. They occur from Puulu to Ikombe on the Northeastern shore and between Ruarwe and Ngara on the West coast. Blue males have been observed in the populations at Katale and Chirwa Islands, also at Makonde. 
The third group occurs at Chitande Island, where the males are indistinguishable from the "Cobalt", but the females are off white with black blotches.