Rhizostome Jellyfish - Mastigias papua

Photograph by Scott Tuason

This scyphozoan jellyfish (Phylum: Cnidaria, Class: Scyphozoa, Order: Rhizostomeae) is one in which, instead of a single central mouth, there are innumerable tiny openings carried on a system of 8 branched, lobed, arm-like appendages that hang below the bell. The enormously subdivided feeding surfaces of the rhizostome, or 'root-mouthed', jellyfish provide an efficient means of screening the water for small planktonic prey. Many tropical species also harbour zooxanthellae in the tissue, which may supplement their nutrition. This species appears to be quite variable in colour and morphology and is widely distributed in the Indo-Pacific. It is about 50 to 100 millimetres across the bell.

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