Notes on the hypselostomatid snails (Gastropoda: Heterobranchia) from limestone hills in Western Cambodia with a new record and a new species

Thirteen hypselostomatid microsnails have been reported so far from Cambodia: 10 species from the Mekong Delta karsts in the south and three species from the Sisophon-Battambang limestone hills in the west. Herein, Gyliotrachela torticollis Benthem Jutting, 1962, the only species previously reported from the Battambang, is redescribed based on near-type locality specimens. We describe a new species, Gyliotrachela khmeriana sp. nov., from the Cambodian Sisophon-Battambang limestone hills. This new species differs from all other known hypselostomatid species in having a short and straight tuba, protoconch sculptures with shallow pits and spiral striations, and apertural dentition with parietal, angular, and four other lamellae on the palatal wall. In addition, specimens of 'Anauchen srakeoensis Panha and Burch, 2004', previously recorded only in Thailand, were collected from limestone hills in Sisophon, redescribed based on shell morphology and taxonomically relocated as a member of the Hypselostoma.http://www.zoobank.org/urn:lsid:zoobank.org:pub:1C13858D-BE2E-45CF-8BEA-B5C99C8A8648