A new species of Gastrophanella from central western Atlantic, with a discussion of the family Siphonidiidae (Demospongiae : Lithistida)

A new species of Gastrophanella, G. cavernicola sp. nov. (Demospongiae: Sip honidiidae), is described from submarine caves in Fernando de Noronha Islan d (north-east Brazil), Carrie Bow Cay and Columbus Gay, Belize (central Wes tern Atlantic), at depths of 5-30 m. It differs from all other species of t he genus by its lobate shape with thin superficial canals and centrotylote tylostrongyles. Gastrophanella cavernicola sp. nov. is the second record of the genus Gastrophanella from both Brazil and the Caribbean. It is the six th 'lithistid' sponge reported from the Brazilian coast, whereas at least 3 2 other desma-bearing sponges are known from the Caribbean. The genus now i ncludes five valid species, G. implexa Schmidt from the West Indies (type s pecies), G. mammilliformis Burton from South Africa, G. primore Gomez from the Pacific Coast of Mexico, G. stylifera Mothes & Silva from south Brazil, and G. cavernicola sp. nov, from north-east Brazil and Belize. Aciculites oxytylota Levi & Levi from New Caledonia is transferred to Siphonidium Schm idt. The family Siphonidiidae Lendenfeld, which is probably related to orde r Hadromerida, is redefined to contain only Siphonidium and Gastrophanella, both with fused rhizoclone desmas associated to microspined exotyles.