Description and life cycle of the hydrozoan Hydractinia uniformis, sp. nov. (Cnidaria: Hydrozoa: Hydractiniidae), from the coast of southeastern Brazil

Abstract

A new species of hydrozoan, assigned here to the genus Hydractinia, is described from the southeastern coast of Brazil (São Paulo state). This new species is distinguished from all known species of the genus Hydractinia by a combination of the following characters: monomorphic colonies, long tentacles of the polyp, production of frustules, and free medusae with branched mouth arms and ocelli.