Diplommatina syabrubesiensis Budha & Backeljau, 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 : 22-23

Diplommatina syabrubesiensis Budha & Backeljau sp. nov.

urn:lsid:zoobank.org:act:1CFD0C16-38F3-489C-9A86-945A6475250B

Figs 8C , 9O

Diagnosis

Measurements (n = 11): SH 2.9–3.2 mm, SW 1.4–1.5 mm, Wh 6.5–7.0; holotype: SH 3.2 mm, SW 1.5 mm, Wh 7.0. Dextral, whorls regularly increasing, penultimate whorl slightly wider than the body whorl, suture impressed, constriction nearly at the middle in front of the parietal wall ( Fig. 9O ). One weak parietalis ( Fig. 8C 3 ). One vertical palatalis. Horizontal palatalis absent ( Fig. 9O ). Columellaris moderate, weak towards the aperture. Protoconch smooth, with minute pits evenly distributed, radial ribs absent ( Fig. 8C 1 ). Teleoconch with distinct radial ribs; 9–11 ribs/ 0.5 mm on the penultimate whorl; 13–16 ribs/ 0.5 mm on the body whorl towards the aperture. Dorsal fold present, but weakly developed ( Fig. 8C 2 , C 4 ). Spiral striation present, but hardly visible. Umbilicus closed. Aperture circular; parietal wall thick, raised and slightly oblique with regard to the coiling axis. Peristome with two slightly spaced lips; angular edge of the peristome straight; palatal lip rounded; basal lip along the columellar margin slightly curved; inner lip slightly thickened and forming a thick callus over the parietal wall. Operculum paucispiral, Wh 2.5, outer whorl comparatively wide.

Etymology

The species name refers to the type locality ‘Syabrubesi’.

Type material

Holotype

NEPAL: Syabrubesi , above Lama Hotel, Langtang National Park, 2635 m, 28.197564 N, 85.455117 E, 13 May 2008, P.B. Budha leg. ( CDZMTU051 ).

Paratypes

NEPAL: 7 shells from the type locality, same data as holotype ( CDZMTU 052); 27 shells, Dhunche, Langtang National Park, 2056m, 28.108942 N, 85.291547E, 3Jun. 2007, P.B. Budha leg. ( CDZMTU 053); 2 shells, Baghdwar-Deurali trek, Shivapuri-Nagarjun National Park, 2406 m, 27.803775 N, 85.38872 E, 25 Apr. 2008, P.B. Budha leg. ( CDZMTU 054).

Remarks

The shell of D. syabrubesiensis sp. nov. is similar to that of D. fistulata sp. nov. However, the peristome of D. fistulata sp. nov. is highly tilted towards the left on the inner wall of the parietal lip on the columellar axis, while it is round in D. syabrubesiensis sp. nov. Moreover, D. fistulata sp. nov. has a strong dorsal fold, which is not distinct in D. syabrubesiensis sp. nov and only visible through careful observation (see Fig. 8C 4 ).

Figures

Fig. 8. A. Diplommatina silvicola Godwin-Austen, 1886 (CDZMTU050). B. D. sperata W.T. Blanford, 1862 (CDZMTU062). C. D. syabrubesiensis sp. nov., holotype (CDZMTU051). The yellow arrow indicates the dorsal fold. 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).

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.