Naticopsis cf. heshanensis Pan & Erwin, 2002

Ketwetsuriya, Chatchalerm, Karapunar, Baran, Charoentitirat, Thasinee & Nützel, Al- Exander, 2020, Middle Permian (Roadian) gastropods from the Khao Khad Formation, Central Thailand: Implications for palaeogeography of the Indochina Terrane, Zootaxa 4766 (1), pp. 1-47 : 29-30

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.

Figures

FIGURE 20. A–C, Naticopsis sp. 1, ESKU-19-LP 47. D–F, Naticopsis sp. 2, ESKU-19-LP 46. G–I, Naticopsis? sp. 3, ESKU- 19-LP 32. J, Naticopsis? sp. 4, ESKU-19-LP 52. K–L, Naticopsis cf. heshanensis Pan & Erwin, 2002, ESKU-19-LP 44. Scale bars represent: 2 mm (A–J); 5 mm (K–L).