Eudistoma clavatum sp. nov. (Tunicata: Ascidiacea: Polycitoridae) from Brazil

Six species of Eudistoma are known on the Brazilian coast, most of them from the tropical part of the country. Here we describe a new species found in shallow waters at 24―27°S, which hang from vertical surfaces or ledges. The colony is formed by clavate lobes connected by the base. The main diagnostic characteristic is the shape of the colony and the larvae which have small projections at the base of the ectodermal ampullae. Other characteristics are: zooid 5-7 mm long with abdomen 3 . 5 times longer than the thorax, not organized in systems, up to 20 longitudinal and 23 transverse muscle bands on the thorax, decreasing number of stigmata from the first (21―24 stigmata per side) to the third row (13―19 stigmata per side), 16 oral tentacles of two sizes arranged in one circle, 8―13 testis follicles, 2―4 embryos developing in a wide atrial cavity, larva 0 . 5 mm long with four pairs of long ampullae and tail winding 3/4 of the way around the trunk.