A new species of Sesara Albers, 1860 from northeastern Thailand (Stylommatophora: Helicarionidae)

ABSTRACTSesara triodon n.sp. is described from the Phu Pha Lom limestone area in Loei, northeastern Thailand. It possesses a small and depressed–conoid, transparent shell with a shiny external surface. The aperture possesses three apertural teeth, in contrast to other Thai species, Sesara parva Solem, 1966 (two teeth) and Sesara megalodon Blanford, 1902 (four teeth). The genital system of the new species has some distinctive characters, including a vagina longer than the free oviduct, and the epiphallic retractor caecum is rounded and bulbous. The radula has 104 rather straight rows of teeth, with each row having74–81 teeth. This is the easternmost record of the genus Sesara in Thailand.http://zoobank.org/urn:lsid:zoobank.org:pub:52EF0AB6-1E17-4B96-BC6F-4257FE5FBF00