Diplommatina prakaiphetensis Boonmachai & Nantarat, 2023

Boonmachai, Tuangthong, Bergey, Elizabeth A. & Nantarat, Nattawadee, 2023, First record and description of three new species in the land snail genus Diplommatina Benson, 1849 (Caenogastropoda, Diplommatinidae) from Satun Province, Thailand, Zoosystematics and Evolution 99 (1), pp. 195-207 : 195

publication ID	https://dx.doi.org/10.3897/zse.99.99030
publication LSID	lsid:zoobank.org:pub:E28DD35A-30EA-4C53-B5A6-F0A80CA0CFC0
persistent identifier	https://treatment.plazi.org/id/C468B471-1728-4C9C-ABC3-4C1530C644D8
taxon LSID	lsid:zoobank.org:act:C468B471-1728-4C9C-ABC3-4C1530C644D8
treatment provided by	Zoosystematics and Evolution by Pensoft
scientific name	Diplommatina prakaiphetensis Boonmachai & Nantarat
status	sp. nov.

Treatment

Diplommatina prakaiphetensis Boonmachai & Nantarat sp. nov.

Figs 2C View Figure 2 , 3G-I View Figure 3

Type material.

Holotype CMUZ 9050066 (Fig. 2C View Figure 2 ); Shell measurements: SH = 1.76 mm, SW = 0.89 mm, AH = 0.66 mm, AW = 0.64 mm, W = 6 1/2. Paratypes CMUZ 9050067-9050071 (5 shells); Shell measurements: SH = 1.62-1.75 mm, SW = 0.83-0.90 mm, AH = 0.59-0.69 mm, AW = 0.61-0.72 mm, W = 6-7.

Type locality.

Thailand, Satun Province, Thung Wa District, Prakaiphet Hill, 7°00'00.1"N, 99°46'08.7"E, 19 January 2022, coll. T. Boonmachai.

Other material examined.

Thailand, Satun Province, Thung Wa District, Prakaiphet Hill , 7°00'00.1"N, 99°46'08.7"E, 19 January 2022: CMUZ 9050072-9050088 (17 shells) GoogleMaps .

Etymology.

The specific epithet prakaiphetensis is an adjective referring to the type locality (Prakaiphet Hill in Na Thon subdistrict, Thung Wa District, Satun Province, Thailand).

Differential diagnosis.

Among sinistral diplommatinids, Diplommatina prakaiphetensis sp. nov. most closely resembles D. krabiensis Panha & J. B. Burch, 1998 from Thailand, and D. karoensis Maassen, 2002 from Sumatra, Indonesia as all these species share a minute size, an ovate shell shape with rather flat whorls, radial ribs being distinct and comparatively widely spaced. However, D. prakaiphetensis sp. nov. differs from both other species in the number of whorls (Table 1 View Table 1 ). It also differs from D. karoensis in the number of radial ribs/0.5 mm on the penultimate whorl and ratio of SH/SW (Table 1 View Table 1 ). Moreover, the absence of radial ribs on the body whorl on the parietal side and slightly wavy radial ribs distinguishes it from D. krabiensis .

Description.

Shell sinistral, fusiform, thin, convex, color Aztec gold, (Figs 2C View Figure 2 , 3G View Figure 3 ). Penultimate whorl width slightly smaller than the body whorl, suture impressed. Constriction level with the middle parietal side of the peristome, with three lamellae: one parietalis, one short transverse palatalis and one prominent columellaris that continues into the tuba and is visible in the aperture (Fig. 4E, F View Figure 4 ). Protoconch smooth, with very fine pits, about 1 1/4 whorl (Fig. 3H View Figure 3 ). Radial ribs are very fine and closely spaced on top of the teleoconch; the following ones are more widely spaced, and become prominent on third to last whorl and are wavy, inconspicuous or almost absent on the body whorl on the parietal side of peristome with about 3-4 ribs/0.5 mm on the penultimate whorl (Table 1 View Table 1 ). Aperture rounded, columellar denticle distinct in the aperture. Peristome double and expanding. The outer peristome expanding beyond the inner, with palatal and columellar side protruding, basal side not protruding, inner peristome expanding with a weak parietal lip. Umbilicus closed. Operculum multispiral, flat, corneous, transparent, slightly concave, outer surface smooth, inner surface smooth with a large ridge and raised peripheral circular edge (Fig. 3I View Figure 3 ). The radula of the taenioglossate type (Fig. 5C View Figure 5 ). The central tooth strong and pointed cusps with a large central cusp, two pairs of developed lateral cusps. The basal plate of the central tooth prominent with two small cusps. The lateral teeth with five cusps; the longest is the third cusp. In the marginal teeth, the inner teeth larger than the outer, with four cusps, and the longest is the second cusp. The outer marginal teeth with three cusps (Fig. 5C View Figure 5 ).