Taxonomic review of Aclis Lóven, 1846 (Gastropoda, Eulimidae) from Brazil with notes on other congeners from the western Atlantic and Saint Helena.

A taxonomic review of Aclis Lóven, 1846 from Brazil led to the discovery of ten species, five of them are new. Before this study, only four species were known from the area. Aclis sarissa Watson, 1881 is revised and reassessed regarding its shell variability. Aclis marplatensis (Castellanos & Landoni, 1984) comb. nov. is here revised and transferred to Aclis based on the presence of spiral keels and microscopic spiral striae on the teleoconch. Additional material of A. watsoni Barros, Lima & Francisco, 2007 is presented here. Aclis macrostoma Barros, Lima & Francisco, 2007 is still known only from the type series. The new species (Aclis pulchra sp. nov., Aclis costai sp. nov., Aclis anaglyptica sp. nov., Aclis corniculata sp. nov. and Aclis multicarinata sp. nov.) can be distinguished from other congeners mainly by the shape, size, sculpture, color pattern, and the presence or absence of an umbilicus. Besides these taxa, three morphotypes from Brazil might represent new species, but are not formally described due to the inadequate material. An overview of the remaining Aclis from the western Atlantic and Saint Helena, based on type material led to the following conclusions: Aclis dalli Bartsch, 1911, Aclis verrilli Bartsch, 1911, and Aclis fernandinae Dall, 1927 are revalidated; Aclis pendata Dall, 1927 is proposed as synonym of Aclis stilifer Dall, 1927; Aclis canaliculata (E.A. Smith, 1890) is reallocated in Aclis. Besides, some species, previously attributed to Aclis are removed from the genus, some of them being reallocated to other gastropod families.