ABYSSOCHRYSIDAE TOMLIN, 1927

Souza, Bruno H. M., Passos, Flávio D., Shimabukuro, Maurício & Sumida, Paulo Y. G., 2021, An integrative approach distinguishes three new species of Abyssochrysoidea (Mollusca: Caenogastropoda) associated with organic falls of the deep south-west Atlantic, Zoological Journal of the Linnean Society 191 : -

FAMILY ABYSSOCHRYSIDAE TOMLIN, 1927

Diagnosis (emended): Gastropods of this family present turreted or globose shells, with prominent axial ribs and covered with a brownish periostracum. Lack of eye globe and two annulated, pallial tentacles that arise from the mantle. Radula is taeniglossate, with central teeth with multiple or a single cusp and a robust lateral tooth.

Remarks: Abyssochrysidae snails are known for inhabiting deep-sea environments ( Tomlin, 1927; Houbrick, 1979; Bouchet, 1991; Killeen & Oliver, 2 0 0 0). The relation to other caenogastropods is uncertain, but they share similarities with Provannidae (superfamily Abyssochrysoidea ), such as the annulated, pallial tentacles and internal anatomy ( Warén & Ponder, 1991). Molecular reconstructions put Littorinidae as a sister-group of the clade Abyssochrysoidea ( Colgan et al., 2007; and after Johnson et al., 2010).

Formerly, only the genus Abyssochrysos was included in the family Abyssochrysidae , presenting six known species with deposit-feeding behaviour, carnivory and parasitism ( Houbrick, 1979; Warén & Bouchet, 2009). In this study, we consider Cordesia as part of this family based on molecular and morphological data obtained in this work (see further below), adding two more species to the group, one of them being described as follows.