Georissa monterosatiana Godwin-Austen & Neville, 1879

Sutcharit, Chirasak, Thach, Phanara, Chhuoy, Samol, Ngor, Peng Bun, Jeratthitikul, Ekgachai, Siriwut, Warut, Srisonchai, Ruttapon, Ng, Ting Hui, Pholyotha, Arthit, Jirapatrasilp, Parin & Panha, Somsak, 2020, Annotated checklist of the land snail fauna from southern Cambodia (Mollusca, Gastropoda), ZooKeys 948, pp. 1-46 : 1

Georissa monterosatiana Godwin-Austen & Neville, 1879 Fig. 6A

Georissa monterosatiana Godwin-Austen & Nevill, 1879: 739, 740, pl. 59, fig. 6. Type locality: Perak [Perak State, Malaysia]. Foon et al. 2017: 43, fig. 16c.

Material examined.

Locality no. 11: CUMZ-CM114 (10 shells; Fig. 6A ). The snails were found to live on limestone wall syntopically with other Hypselostoma spp.

Distribution.

Thailand and Malaysia ( Foon et al. 2017).

Remarks.

This species was described from “Perak” [Perak State, Malaysia]. The characters of this minute shell are elongate conic, yellowish to pale orange with darker colour on apex. The shell has four to five well-rounded whorls, with wide and impressed suture. Protoconch surface is smooth, with the following whorls sculptured with strong, regularly spaced spiral ribs and with ca. 9-11 spiral ribs on the last whorl (more thin spiral ribs at basal part of the last whorl). The aperture is round to slightly ovate, with a closed umbilicus. Although the specimens from Perak have denser spiral striation ( Godwin-Austen and Nevill 1879, Foon et al. 2017), without a comprehensive revision of this genus the specimens from Cambodia were hereby identified as G. monterosatiana .

This species differs from G. decora Möllendorff, 1900 and G. chrysacme Möllendorff, 1900 both of which were described from “Touranne” [Da Nang, Vietnam], by having a conic shell with ca. ten strong spiral ribs on the last whorl. However, G. decora has an ovate conic shape with fine radial ribs on the last whorl, and G. chrysacme has an elongate conic shape with a deep and narrow suture. In addition, the shell shape of G. monterosatiana approaches the shape of G. insulae Khalik et al., 2019 from Borneo, but the former species has stronger and more undulated spiral ridges than the Bornean species (see Khalik et al. 2019).

Figures

Figure 6. A Georissa monterosatiana Godwin-Austen & Neville, 1879 B Georissa carinata Sutcharit & Jirapatrasilp, sp. nov. C Cyclophorus amoenus (Pfeiffer, 1854) D Cyclophorus paviei Morlet, 1885 E Opisthoporus bernardii (Pfeiffer, 1862) and F Lagocheilus landesi (Morlet, 1885).