Taxonomic Assessment Of Triphoroidea And Eulimidae (Caenogastropoda) From The Rio Grande Rise, Southwestern Atlantic Ocean

This study provides a taxonomic evaluation of the deep-sea microgastropods belonging to Triphoroidea and Eulimidae from the Rio Grande Rise (southwestern Atlantic), whose shells were photographed right before the destruction of the material during the fire at Museu Nacional, Brazil, in September 2018. A total of 22 taxa was sampled, 9 belonging to Triphoroidea, 13 to Eulimidae. The new records of 4 species of Eulimidae, the western Atlantic Costaclis hyalina, Halielloides hyalina (Watson, 1883) comb. nov., and Melanella sarissa and the northeastern Atlantic Eulima grimaldii, represent a large increase in the known geographic range. Two species of Triphoroidea from the northeastern Atlantic (Cerithiella insignis and Ektonos turbonilloides) require confirmation in the Rio Grande Rise. Several taxa require additional material in order to discern whether they constitute new species and to enable formal descriptions; they are allocated in genera known for comprising deep-sea species, both in Triphoroidea (Cerithiella, Krachia, Onchodia, Strobiligera) and Eulimidae (Batheulima, Costaclis, Curveulima, Fuscapex, Hemiaclis, Melanella). The present study reinforces the urgent need for a good conservation and a proper infrastructure of scientific collections.