Sarika gratesi Pholyotha & Panha, 2020

Pholyotha, Arthit, Sutcharit, Chirasak, Tongkerd, Piyoros & Panha, Somsak, 2020, Integrative taxonomic revision of the land snail genus Sarika Godwin-Austen, 1907 in Thailand, with descriptions of nine new species (Eupulmonata, Ariophantidae), ZooKeys 976, pp. 1-100 : 1

Sarika gratesi Pholyotha & Panha sp. nov. Figs 49 , 50A, B

Type material.

Holotype CUMZ 7275 (Fig. 50A , width 16.5 mm, height 8.8 mm). Paratypes CUMZ 7276 (10 shells; Fig. 50B , width 16.0 mm, height 8.3 mm), 7912 (30 shells), NHMUK 20200289 (two shells), SMF (two shells), ZRC.MOL.017031 (two shells).

Other material examined.

Thailand-Northeastern. Dry dipterocarp forest at Phu Lan Kha, Nong Bua Daeng, Chaiyaphum, 16°00'00.9"N, 101°52'33.4"E: CUMZ 7277.

Type locality.

The limestone outcrop with dry deciduous forest at Tham Phraya Nakarat (Cave), Chum Phae, Khon Kaen, Thailand, 16°48'30.3"N, 101°57'13.7"E.

Diagnosis.

Shell medium-sized, depressed to strongly depressed, and pale brown. Aperture irregular with peristome rather simple above then expanded middle with curved inside aperture and thickened below periphery.

Description.

Shell. Shell depressed to strongly depressed or nearly flattened, medium-sized (shell width up to 17.4 mm, shell height up to 8.8 mm), rather thin, and slightly opaque. Shell surface smooth, polished and with thin growth lines; shell colour pale brown. Whorls 6-7, increasing regularly; body whorl large and well rounded. Spire little to moderately elevated; suture impressed. Aperture crescent-shaped and open obliquely; peristome irregular. Apertural lip at upper periphery simple; at periphery with invagination of triangular lip (beak-like); at below periphery rather thickened inside aperture and little expanded. Columellar margin straight, slightly thickened and expanded near umbilicus. Umbilicus narrowly opened (Fig. 50A, B ).

Etymology.

The specific name gratesi is named in honour to Admiral Chorchat Gra-tes of the Royal Thai Navy, who made possible many fieldtrips especially the remote islands areas in Thailand.

Distribution.

Sarika gratesi sp. nov. is currently known from the restricted area of the dry deciduous and dry dipterocarp forests in Khon Kaen and Chaiyaphum provinces (Fig. 49 ).

Remarks.

This new species is easy to distinguish from all known Sarika as well as Macrochlamys species by its unique beak-like lip, while all other species in these two genera have simple to little thickened lips. Only, Macrochlamys aspides ( Benson 1863) from Myanmar tends to have a slightly thickened and expanded lip at below periphery, but Sarika gratesi sp. nov. has a projecting and curved triangular shape lip at the periphery. Sarika gratesi sp. nov. is identical to Sarika because its shells are matched with Sarika more than the Siam Macrochlamys ( Pholyotha et al. 2018).

Figures

Figure 49. Geographic distribution of Sarika gratesi sp. nov. based on the specimens examined herein.

Figure 50. Shells of Sarika spp. A, B Sarika gratesi sp. nov. A holotype CUMZ 7275 and B paratype CUMZ 7276 C, D S. pumicata syntype NHMUK 1893.2.4.980 - 981 E S. ochtogyra holotype SMF 227103 / 1 F S. benoiti modified from Crosse and Fischer (1863) G S. rex modified from Preston (1909).