"Astochoporella gen. nov.
Diagnosis
Colony forming folded, unilaminar sheets, loosely encrusting or erect. Frontal wall of autozooids with umbonuloid development, displaying well marked marginal septula. Aperture thin-rimmed, lacking denticles ; rounded distally, straight or slightly convex proximally. Operculum supported distally by a narrow, calcified vestibular arch, continuous proximally on each side with a basally- deflected, dentate, occlusor lamina. Ovicell developed as a submersed expansion of the distal wall of the maternal autozooid, with ooecial cover developed from the frontal wall of the distally succeeding autozooid ; closed by autozooidal operculum. Frontal adventitious avicularia present proximal to aperture.
Type species : Astochoporella cassidula nom. nov.
Discussion
A. cassidula nom. nov. is introduced for Pemmatoporella marginata Hayward and Taylor (1984), non Calvet (1909). Its familial placing is problematic. It is superficially similar to certain genera within the Smittinidae, including Pemmatoporella, but its umbonuloid frontal wall ontogeny and its dentate occlusor laminae indicate that it is systematically remote from that particular cheilostome grouping. For the present it may be placed among the Umbonulidae, with the reservation that the Umbonulacean families now seem to be increasingly heterogenous assemblages of genera which will eventually require substantial systematic reassessment." (Hayward and Thorpe, 1988)
