Amphiprion clarkii

Common Name: Maldivian Clark’s Anemonefish

Scientific Name: Amphiprion clarkii (J. W. Bennett, 1830)

Distribution: Maldives, Sri Lanka, probably Southern India

Type Locality: Southern coast of Sri Lanka

Identification: Caudal fin bright yellow in both sexes, obscuring most or all of the posterior stripe. Dorsal fin black throughout; ventral fins yellow. Base coloration of body shows through only near pectoral fin base and head. Melanistic form entirely black; the anal fin darkens first.

Similar: Specimens from Oman tend to have thinner stripes that often fail to connect above the head, but, in other respects, they appear identical to the true Amphiprion clarkii found at Sri Lanka and the Maldives. Those from the Andaman and Java Sea are also nearly identical, but have noticeably thicker stripes and tend to have less of the posterior stripe hidden by the yellow coloration of the tail.

Notes: The Indian Ocean population as a whole is remarkably homogeneous given how variable those from the Pacific appear. It would be interesting to know if this is due to a recent expansion and colonization across the region.

There appears to be a large disjunction separating the Persian Gulf and Indian populations, caused by the discharge of several river systems that inhibit reef development. A study of the population genetics is warranted here to determine the age of this split and whether this Arabian fish is truly worthy of species recognition. Aquarium specimens from the Maldives and Sri Lanka are reasonably common.