Family Uncinateridae fam. nov.

Abstract

Uncinateridae fam. nov. (Hexactinellida, Hexasterophora, Aulocalycoida) is formed from Uncinatera Topsent, a genus never accorded a secure position within the various hexactinosidan families, and the troublesome, and usually avoided Tretopleura Ijima, variously regarded as an aulocalycid or euretid. Review of original descriptions and type specimens has shown both genera have dictyonal frame- works characterized as a variant of the revised aulocalycoid pattern – here designated as paraulocalycoid. The pattern differs from aulo- calycoid in having multiaxial longitudinal strands and no synapticula. The family presently consists of three species in two genera which are restricted in distribution to two distinct regions, Antarctica S of Chile, and tropical W Pacific Ocean.