Pseudoiglica olsavskyi, Grego, Jozef, 2018

Grego, Jozef, 2018, First record of subterranean rissoidean gastropod assemblages in Southeast Asia (Mollusca, Gastropoda, Pomatiopsidae), Subterranean Biology 25, pp. 9-34 : 13-15

Pseudoiglica olsavskyi sp. n. Figs 7-8

Type locality.

Laos; Khammouane Province, Ban Na village 20 km NNE of Thakhek, Tham Khon Dôn Cave 17°33.82'N; 104°52.30'E, 161m a.s.l., Earthquake Dome 3 km from the south entrance, sand sediments on cave river bank (Fig. 2B).

Type material.

Holotype: type locality: J. Grego and M. Olšavský leg. 11-12 February 2017 (NHMUK 20180003). Paratypes: type locality (NHMUK 20180149 - 1 specimen; coll. Grego F0872 - 3 specimens); Laos, Khammouane Province, Tham Nam Dôn Cave 17°33.82'N; 104°52.30'E, 161 m a.s.l., temporary side rivulet sediment at entrance passage 1.5 km from the main entrance, dry sand on the cave floor; J. Grego leg. 11 February 2017 (coll. Grego F0864 - 3 specimens); Laos, Khammouane Province, 3 km NW of Ban Na Village, sand on the bottom of Nam Dôn River source at 149 m a.s.l.; J. Grego leg. 07 February 2017, 17°33.20'N; 104°52.38'E (coll. Grego F0854 - 4 specimens) (Fig. 2A).

Measurements.

Holotype: H 2.45 mm; W 0.85 mm; BW 0.52 mm; BH 1.00 mm; AH 0.61 mm; AW 0.45 mm; H/W 2.88; AH/AW 1.36; W/BW 1.63; H/BH 2.45; H/AH 4.02; W/AW 1.89

Diagnosis.

The tiny, elongated cylindrical shell of P. olsavskyi sp. n. with a proportionally very small aperture distinguishes this species from all other known members of the genus, which all have larger shells.

Description.

The tiny milky shell has six flattened convex whorls with a deep suture and a blunt apex. The surface is smooth and shiny. The shell is cylindrically elongated, slightly narrowing towards the apex. Umbilicus is slit-like. In frontal view, the aperture protrudes laterally from the shell periphery outline. Aperture is ovoid, separated from the body whorl by a weak furrow. The peristome margin is sharp, equally thick all the way around and very slightly reflexed outwards. The outer lip is sinuous in its lateral profile and its lower end scooped backward.

Etymology.

Named after my friend Mario Olšavský, a geologist and speleologist from Banská Bystrica, Slovakia, who actively participated in sample collection in the cave Tham Khon Dôn.

Distribution.

Only known from the type locality and nearby sites in Tham Khon Dôn Cave as well as from the related source of Nam Dôn River

Ecology.

The same as Pseudoiglica pseudoiglica sp. n.