Genus Hypselostoma Benson 1856

Hypselostoma Benson 1856b, The Annals and Magazine of Natural History, ser. 2, no. 17: 342. (nom. n. for Tanystoma Benson 1856a, non Latreille, 1829).

Type species.

Tanystoma tuberiferum Benson, 1856 by monotypy.

Remarks.

Systenostoma edentata Panha & Burch, 1999 differs from all former, Thai Systenostoma species by the relatively large, toothless, adnate aperture. It is probably a toothless member of a hypselostomatid genus other than former Systenostoma . Here, Systenostoma edentata is placed within the genus Hypselostoma because its similarity with Hypselostoma panhai Burch & Tongkerd, 2002. Hypselostoma panhai is not a typical member of the genus Hypselostoma in terms of shell characters, but was placed into this genus based on molecular data of Tongkerd et al. (2004).