Diplommatina maipokhariensis Budha & Naggs, 2017

Budha, Prem B., Naggs, Fred & Backeljau, Thierry, 2017, The genus Diplommatina Benson, 1849 (Gastropoda: Caenogastropoda: Diplommatinidae) in Nepal, with the description of seven new species, European Journal of Taxonomy 337, pp. 1-30 : 12

Diplommatina maipokhariensis Budha & Naggs sp. nov.

urn:lsid:zoobank.org:act:EF1CC77A-F108-4578-B32E-7EBAF2F9EB22

Figs 4C , 9F

Diagnosis

Measurements (n = 6): SH 2.4–2.5 mm, SW 1.1–1.2 mm, Wh 7.2–7.5; holotype: SH 2.5 mm, SW 1.1 mm, Wh 7.5. Dextral, penultimate and body whorls nearly equal in width. Constriction at the inner edge of the parietal wall of the lip ( Fig. 9F ). Parietalis long and distinct ( Fig. 4C 3 ). Two vertical palatalis: Vpt1 distinct and strong, running along the constriction; Vpt2 thin, running parallel to Vpt1. Two horizontal palatalis running closely together giving the impression of a single lamella above the columella ( Fig. 9F ). Columellaris prominent. Columellar tooth distinct. Protoconch smooth, Wh approx. 2.0, with very distinct pits, without radial ribs ( Fig. 4C 1 ). Teleoconch with widely spaced strong radial ribs, evenly distributed on the penultimate and body whorls; about 4–6 ribs/ 0.5 mm ( Figs 4C 2 , 4C4 ). Fine spiral striation present. Umbilicus closed. Aperture circular. Peristome with two widely spaced lips; 6–8 ribs between the lips ( Fig. 4C4 ). Both lips slightly reflected.

Etymology

The species name refers to the type locality of Maipokhari, one of the Ramsar sites of Nepal.

Type material

Holotype

NEPAL: Maipokhari , Ilam, 2030 m, Cryptomeria forest, 27.001111 N, 87.92222 E, 25 Dec. 2010, P.B. Budha leg. ( CDZMTU034 ).

Paratypes

NEPAL: 10 shells from the type locality, same data as holotype ( CDZMTU 035).

Remarks

The shell of Diplommatina maipokhariensis sp. nov. looks intermediate between the Philippine species D. concolor Quadras & Möllendorff, 1893 ( Zilch 1953: p. 28, fig. 156) and the Burmese (= Myanmar) species D. exilis W.T. Blanford, 1863 ( Hanley & Theobald 1876: pl. 119, fig. 10). Yet, it differs from both these species by its broader whorls. Diplommatina exilis also differs from D. maipokhariensis sp. nov. in the more slender shell and the absence of spiral striations.

Another slender species is D. exserta Godwin-Austen, 1886 (pl. 49, figs 2, 2a), which is larger and lacks a prominent constriction. The most similar species is D. pullula Benson, 1859 from Darjeeling, but D. maipokhariensis sp. nov. has stronger radial ribs and a smaller shell (SH <2.5 mm) than D. pullula (SH> 3 mm).

Figures

Fig. 4. Diplommatina Benson, 1849 of Nepal. A. D. folliculus (L. Pfeiffer, 1846) (CDZMTU028). B. D. godawariensis sp. nov., holotype (CDZMTU032). C. D. maipokhariensis sp. nov., holotype (CDZMTU034). Scale bar in images A2, A4, B2, B4, C2, C4 is 500 µm.

Fig. 9. Palatal lamellae (palatalis) of species of Diplommatina. Dotted lines indicate the position of the constriction. Dark lines indicate the palatalis. A. D. abiesiana sp. nov. B. D. exserta Godwin- Austen, 1886. C. D. fistulata sp. nov. D. D. folliculus (L. Pfeiffer, 1846). E. D. godawariensis sp. nov. F. D. maipokhariensis sp. nov. G. D. miriensis Godwin-Austen, 1917. H. D. munipurensis Godwin- Austen, 1892. I. D. oviformis Fulton, 1901. J. D. regularis Fulton, 1901. K. D. salgharica sp. nov. L. D. shivapuriensis sp. nov. M. D. silvicola Godwin-Austen, 1886. N. D. sperata W.T. Blanford, 1862. O. D. syabrubesiensis sp. nov.

Fig. 3. Diplommatina Benson, 1849 of Nepal. A. D. abiesiana sp. nov., holotype (CDZMTU020). B. D. exserta Godwin-Austen, 1886 (CDZMTU024). C. D. fistulata sp. nov., holotype (CDZMTU025). The yellow arrow indicates the dorsal fold. Scale bar in images A2, A4, B2, B4, C2, C4 is 500 µm.

Fig.1. Map of the localities and areas surveyed for Diplommatina spp. in Nepal.

Fig. 2. Shell terminology. A. D. regularis Fulton, 1901. B. D. folliculus (L. Pfeiffer, 1846). C. General outline of the lower part of a shell from Diplommatina species. Abbreviations: Prt = Parietalis (Prt1 = inner parietalis, Prt2 = outer parietalis); Pt = Palatalis; Hpt = Horizontal palatalis (Hpt1 = lower, Hpt2 = upper in case of two); Vpt = Vertical palatalis (Vpt1 = left side, Vpt2 = right side in case of two).