Diversity and systematics of Haminoeidae gastropods (Heterobranchia: Cephalaspidea) in the tropical West Pacific Ocean: new data on the genera Aliculastrum, Atys, Diniatys and Liloa Author Too, Chin Chin Author Carlson, Clay Affiliated to: Marine Laboratory, University of Guam, Mangilao, GU 96923 Author Hoff, Patty Jo Affiliated to: Marine Laboratory, University of Guam, Mangilao, GU 96923 Author Malaquias, Manuel António E. text Zootaxa 2014 2014-05-07 3794 3 355 392 journal article 5612 10.11646/zootaxa.3794.3.3 74c8a3cd-c737-41aa-b574-04ef00c173f7 1175-5326 4914927 A9A30A4F-D095-47EE-9120-B0B5A7BCCE88 Genus Atys Montfort, 1810 Type species: Atys naucum ( Linnaeus, 1758 ) Type locality. Ambon region, Indonesia (based on Rumphius 1705 ) . The genus Atys was first introduced by Montfort (1810) with type species Atys cymbulus Montfort, 1810 . This species was considered a synonym of Bulla naucum Linnaeus, 1758 by Pilsbry (1895) , and apparently even before by Sowerby (1870) . Montfort (1810) referred the species to the African coast, although he did not specify the exact locality; though, the author was likely referring to the east coast of Africa, because A. naucum is only known in the Indo-West Pacific. Species have been ascribed to this genus mostly based on shell morphology. The genus is characterized by umbilicate oval-elongate or inflated shells, with spiral grooves. The gizzard plates are covered with tiny rods and the radula has a median tooth ( Bergh 1901 ; Lin 1997 ; Carlson & Hoff 1999 ). Species of the genus Atys are commonly found on shallow sandy bottoms in tropical and temperate regions and about 50 species have been reported in the Indo-West Pacific ( OBIS 2012a ) (see Tab. 2 for diagnostic characters of species described here).