Acinolaemus cryptidentatus Changlom, Chan-ard & Dumrongrojwattana, 2019

Figs 2B, 13B

Acinolaemus cryptidentatus Changlom et al., 2019: 158, 159, fig. 2a-f. Type locality: Tham Wua (Wua Cave), Mueang District, Mae Hong Son Province [Thailand].

Material examined.

Monastery, Ywangan Township, Taunggyi District, Shan State, Myanmar (locality code SH12; 21°13'43.3"N, 96°33'19.2"E): CUMZ 14413 (1 shell; Figs 2B, 13B) .

Remarks.

This species was recently described from a limestone outcrop in northern Thailand that is ~ 200 km southeast of Taunggyi District, Shan State, Myanmar. This single specimen from Shan State slightly differs from the type specimen in having weak radial ridges and many weak interpalatal lamellae; whereas the type specimen possesses strong radial ridges and is without interpalatal lamellae. Further surveys should employ specialised sampling techniques (i.e., multiple series of sieves) that yield more specimens, which will clarify the identity of these tiny shells.

Acinolaemus cryptidentatus differs from A. ptychochilus and A. mueangonensis in having a shouldered last whorl and weak upper and lower palatal lamellae. In comparison, A. ptychochilus possesses a rounded last whorl, strong upper and lower palatal lamellae, and a strong infraparietal lamella. Meanwhile A. mueangonensis has a less-shouldered last whorl and lacks interpalatal lamellae (Thompson and Upatham 1997; Changlom et al. 2019).