Middle Permian (Roadian) gastropods from the Khao Khad Formation, Central Thailand: Implications for palaeogeography of the Indochina Terrane Author Ketwetsuriya, Chatchalerm Author Karapunar, Baran Author Charoentitirat, Thasinee Author Nützel, Al- Exander text Zootaxa 2020 2020-04-17 4766 1 1 47 journal article 22833 10.11646/zootaxa.4766.1.1 ed4d1bf6-284a-4898-952a-58943d5a3026 1175-5334 3763907 urn:lsid:zoobank.org:pub:B1B5DA41-5035-4783-8D47-28857B6305AE Naticopsis cf. heshanensis Pan & Erwin, 2002 ( Fig. 20 K–L) cf. Naticopsis ( Naticopsis ) heshanensis Pan & Erwin, 2002: 21 , fig. 11.12–11.17 . Material. One specimen: ESKU-19- LP 44. Dimensions (mm): ESKU-19- LP 44: height = 19.0; width = 16.2; apical angle = 124 º . Description. Subglobose shell, very low-spired, medium-sized, comprising c . 3.5 whorls; apex obtuse; whorls rapidly increasing; body-whorl large and inflated, with flatly convex periphery; whorls embracing on preceding whorl, well above periphery; whorl surface with numerous fine, prosocyrt, distinct growth lines; suture adpressed; base convex; aperture unknown. Remarks. This single globose shell with distinct, dense growth-lines resembles Naticopsis ( Naticopsis ) heshanensis Pan & Erwin, 2002 (p. 21, fig. 11.12–11.17) as reported from the Permian of Guangxi Provinces, South China , although the present specimen has a much lower spire than the holotype of N . ( N .) heshanensis . The Permian species N . permica Netchaev, 1894 as illustrated by Mazaev (2015 , p. 959, pl. 33, figs 1–5) from the Middle Permian of Volga Region, Russia is similar but has a higher spire, more convex whorls and less distinct growth lines.