Shallow-water Rissoidae of the genera Alvania, Haurakia, Parashiela, Simulamerelina and Subestea (Gastropoda, Caenogastropoda, Rissooidea) from French Polynesia, with the description of a new deep-water genus

The extant species of the genera Alvania Risso, 1826, Haurakia Iredale, 1915, Parashiela Laseron, 1956, Simulamerelina Ponder, 1985 and Subestea Cotton, 1944 (Rissoidae Gray, 1847) collected in the shallow waters of French Polynesia are herein revised, for a total of 19 species. Additionally, a new genus for a new deep-water species is here introduced. Two species with wide range in the Pacific are reported: Haurakia marmorata (Hedley, 1907) and Parashiela ambulata Laseron, 1956. Five species of Alvania, one of Ellenstrongia n. gen., five of Parashiela, six of Simulamerelina and one Subestea are described as new: Alvania letourneuxi n. sp., Alvania herosae n. sp., Alvania parvimaculata n. sp., Alvania prosocostata n. sp., Alvania uapou n. sp., Ellenstrongia tarasoc n. gen., n. sp., Parashiela expansilabrum n. sp., Parashiela obesula n. sp., Parashiela rimatara n. sp., Parashiela rotundata n. sp., Parashiela soniae n. sp., Simulamerelina australes n. sp., Simulamerelina densestriata n. sp., Simulamerelina gracilis n. sp., Simulamerelina lepteseiras n. sp., Simulamerelina micrometrica n. sp., Simulamerelina tuamotu n. sp., Subestea moruroa n. sp. Three taxa are transferred to Alvania: Rissoa denseclathrata Thiele, 1925, Rissoa lusoria Yokoyama, 1926, Rissoa proditoris Thiele, 1925. Twelve species have a non-planktotrophic development; five of them are endemic to a single archipelago: Alvania letourneuxi n. sp., Simulamerelina gracilis n. sp., Simulamerelina tuamotu n. sp. to Tuamotu; Simulamerelina densestriata n. sp. to Australes, Parashiela soniae n. sp. to Marquesas. Of the eight species with planktotrophic development, two are apparently endemic to a single archipelago: Parashiela obesula n. sp. and Parashiela rimatara n. sp. to Australes.