Hypselostoma smokon

Hypselostoma smokon (Panha & J. B. Burch, 2004) Anauchen smokon Panha & Burch in Panha et al. 2004: 60, fig. 3. Hypselostoma smokon — Panha and Burch 2008: 99–100, fig. 85; Dumrongrojwattana and Wongkamhaeng 2024: 324, fig. 8. Type material examined. Thailand • 2 paratypes; from the type locality; S. Panha leg.; SMF 331457. Type locality. “ Smokon Mountain, Banmi District, Lopburi Province, 14°54'54"N, 100°29'45"E, 30 meters elevation ”. Differential diagnosis. This species is similar in shell shape to H. chedi and H. khaochakan. From them, H. smokon clearly differs by the concrescent angular and parietal lamellae. It is most similar to H. chedi which has its last whorl bluntly keeled (shouldered in H. smokon) and narrower umbilicus. Distribution. This species is known only from the type locality. Remarks. In the original description, the species was placed in the genus Anauchen because of the absent angular lamella. However, it is present as an angular part of the joined angulo-parietal lamella which justifies its placement in the genus Hypselostoma.