Diplommatina bulonensis 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/94CA70AE-54F1-4B9D-8604-29766AE5FB80
taxon LSID	lsid:zoobank.org:act:94CA70AE-54F1-4B9D-8604-29766AE5FB80
treatment provided by	Zoosystematics and Evolution by Pensoft
scientific name	Diplommatina bulonensis Boonmachai & Nantarat
status	sp. nov.

Treatment

Diplommatina bulonensis Boonmachai & Nantarat sp. nov.

Figs 2A View Figure 2 , 3A-C View Figure 3

Type material.

Holotype CMUZ 9050001 (Fig. 2A View Figure 2 ); Shell measurements: SH = 2.72 mm, SW = 1.27 mm, AH = 0.94 mm, AW = 0.91 mm, W = 6 1/2. Paratypes CMUZ 9050002-9050006 (5 shells); Shell measurements: SH = 2.58-2.82 mm, SW = 1.26-1.34 mm, AH = 0.97-1.04 mm, AW = 0.92-1.03 mm, W = 6 1/2-7 1/2.

Type locality.

Thailand, Satun Province, La-ngu District, Bulon Pai Island on limestone rocks and under leaves, 6°49'53.3"N, 99°35'19.5"E, 22 December 2020, coll. T. Booonmachai.

Other material examined.

Thailand, Satun Province; La-ngu District, Bulon Pai Island, 6°49'53.3"N, 99°35'19.5"E, 22 December 2020: CMUZ 9050007-9050016 (10 shells); La-ngu District , Bulon Pai Island , 6°49'53.3"N, 99°35'19.5"E, 15 February 2022: CMUZ 9050017-9050018 (2 shells) GoogleMaps .

Etymology.

The specific epithet bulonensis is an adjective referring to the type locality (Bulon Pai Island in Satun Province, Thailand).

Differential diagnosis.

Among approximately 400 species of Diplommatina , the new species is most similar to D. conditioria Maassen, 2007, D. baliana Fulton, 1899, D. maduana Laidlaw, 1949, D. gomantongensis Smith, 1894 and D. antheae Vermeulen, 1993 (Table 1 View Table 1 ). Typical characteristics shared by D. bulonensis with all these species are shell dextral with a slender fusiform shape with rather evenly rounded sides, radial ribs not sinuous, constriction situated halfway on the parietal side of the peristome and aperture round. However, D. bulonensis sp. nov. differs from D. gomantongensis and D. antheae by the presence of a transverse palatalis and an inconspicuous columellar denticle in the aperture (Fig. 4A View Figure 4 ). D. bulonensis sp. nov differs in the combination of shell height, shell width, aperture height and aperture width from D. maduana and D. antheae (Table 1 View Table 1 ). D. bulonensis sp. nov differs from D. conditioria and D. maduana in the number of whorls (Table 1 View Table 1 ) and differs from D. maduana , D. gomantongensis , D. antheae and D. baliana in the number of radial ribs/0.5 mm on the penultimate whorl (Table 1 View Table 1 ). D. bulonensis sp. nov has fewer radial ribs on body whorls above the aperture than D. conditioria (12-13 vs. 16 ribs/1 mm) ( Maassen 2007). Moreover, it differs from D. baliana in having a columella fold.

Description.

Shell dextral, fusiform, convex and red rushes or red-orange in color (Figs 2A View Figure 2 , 3A View Figure 3 ). Penultimate whorl slightly wider than body whorl, side flat. Spire conical with slightly convex sides. Suture impressed. Constriction level with the middle parietal side of the peristome, with three lamellae: one parietalis very distinct, one distinct and long transversal palatalis and one distinct columellaris. (Fig. 4A, B View Figure 4 ). Protoconch smooth with dimples and about 2 1/2 whorls (Fig. 3B View Figure 3 ). Radial ribs straight, inconspicuous but distinct, moderately spaced about 6 1/2-7 ribs/0.5 mm on the penultimate whorl (Table 1 View Table 1 ). The aperture slightly tilted against the coiling axis, columellar denticle slightly weak in the aperture. Peristome double, rather expanding, palatal side not sinuous, basal side and columella side weakly sinuous. Outer peristome expanded less than inner peristome, inner peristome expanded at parietalis side, with a palatal lip. Umbilicus closed. Operculum multispiral, flat, corneous, transparent, slightly concave, outer surface smooth, inner surface smooth with raised peripheral circular margin (Fig. 3C View Figure 3 ). The radula of the taenioglossate type (Fig. 5B View Figure 5 ). The central tooth round and flat with seven cusps of similar size. The basal plate of the central tooth, cuspate and small. The lateral teeth with five cusps. The marginal teeth with inner and outer teeth, the inner teeth with seven small cusps and the outer teeth with five cusps and larger than the inner teeth (Fig. 5B View Figure 5 ).