Diplommatina folliculus (L. Pfeiffer, 1846 )

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 : 9-11

Diplommatina folliculus (L. Pfeiffer, 1846)

Figs 2B, 4A, 9D

Bulimus folliculus Pfeiffer, 1846: 83 .

Bulimus folliculus – Pfeiffer 1848: 81–82.

Diplommatina folliculus – Godwin-Austen 1868: 83, pl.1, figs 1–2. — Hanley & Theobald 1876: 56, pl. CXL, figs 8–9. — Gude 1921: 314. — Naggs 1997: 58.

Diplommatina (D.) folliculus – Ramakrishna et al. 2010: 86.

Diplommatina (Diplommatina) folliculus – Budha et al. 2015: p. 6.

Diagnosis

Measurements (n = 15): SH 2.6–3.0 mm, SW 1.2–1.4 mm, Wh 6.5–7.0. Dextral, penultimate whorl slightly wider than the body whorl. Constriction at the middle of the parietal wall ( Fig. 9D). Internally with two parietal lamellae, both Prt1 and Prt2 very short, prominent at the lodging edge of the operculum ( Figs 2B, 4A 3). Two vertical palatal lamellae: Vpt1 along the constriction and Vpt2 short, but running parallel to Vpt1. No horizontal palatal lamella ( Fig. 9D). Columellaris thin. Columellar tooth visible in the aperture. Protoconch smooth, Wh 1.5–2.0, with fine pits. Teleoconch with radial ribs visible only after the second whorl; widely spaced radial ribs; 6–7 ribs/ 0.5 mm on the penultimate whorl; 4–6 ribs/ 0.5 mm on the body whorl towards the aperture ( Fig. 4A 2, A 4). Spiral striation distinct. Umbilicus closed. Aperture circular. Peristome with two lips and expanded; lips widely spaced, sinuous at the angular edge. Outer lip slightly reflected. Operculum paucispiral, corneous, thin, transparent, slightly concave, outer surface smooth, inner surface with peripheral circular edge which is thicker at columellar margin.

Material examined

NEPAL: 80+ shells, Phulchowki Hill, Lalitpur District, 1551–2298 m, 27.580434 N, 85.387538 E, 3–11 May 2007, P.B. Budha leg. ( CDZMTU 028); 95 shells, Shivapuri-Nagarjun National Park, 2314– 2716 m, 27.812591 N, 85.378807 E, 24–21 Jun. 2007, P.B. Budha leg. ( CDZMTU 029); 100+ shells, Shivapuri-Nagarjun National Park, 2314–2716 m, 27.812591 N, 85.378807 E, 24–26 Apr. 2008, P.B. Budha leg. ( CDZMTU 029b); 2 shells, Raniban, Balaju, Kathmandu, 1373 m, 27.7426 N, 85.2847E, 12 Mar. 2009, Srijana Khanal leg. ( CDZMTU 030); 100+ shells, Dhunche, Langtang National Park, 2056–2663 m, 28.106128 N, 85.303259 E, 2 Jun. 2007 and 11 May 2008, P.B. Budha and R. Devkota leg. ( CDZMTU 031).

Remarks

Diplommatina folliculus is a very common, abundant and distinct species that can be distinguished from the others by its strong, widely-spaced lips and costulated radial ribs. It is distributed from the western to the eastern Himalaya. The most similar species is D. silvicola Godwin-Austen, 1886 (pl. LXV, figs 3, 3a), but D. folliculus differs by its more slender shell and less distinct columellar tooth.