Kartvelobia shishaensis Grego & Mumladze, 2020

Grego, Jozef, Mumladze, Levan, Falniowski, Andrzej, Osikowski, Artur, Rysiewska, Aleksandra, Palatov, Dimitry M. & Hofman, Sebastian, 2020, Revealing the stygobiotic and crenobiotic molluscan biodiversity hotspot in Caucasus: Part I. The phylogeny of stygobiotic Sadlerianinae Szarowska, 2006 (Mollusca, Gastropoda, Hydrobiidae) from Georgia with descriptions of five new genera and twenty-one new species, ZooKeys 955, pp. 1-77 : 1

Kartvelobia shishaensis Grego & Mumladze sp. nov. Plates 4 (1, 2, 8, 9); 5(2, 4)

Type locality.

Georgia • Samegrelo, Mukhuri, Shisha Spring; 42°37'47"N, 42°11'26"E; 250 m a.s.l.; sediment from the spring lake bottom.

Material.

Holotype: Georgia • 1 adult, dry; type locality; 42°37'47"N, 42°11'26"E; 250 m a.s.l.; 10 May 2018; J. Grego, L. Mumladze and M. Olšavský leg.; ISU FM-T019-H. Paratypes: Georgia • same as for holotype; ISU FM-T019-P1/3 dry, SBMNH 633084/2 dry, coll. JG F1043/3 dry; • same as for holotype; 12 October; 2019; J. Grego, L. Mumladze and G. Bananashvili leg.; NHMW 113373 ISU-T019-P2/4 dry, coll JG F1056/4 dry; Georgia • Samegrelo, Mukhuri, Mapeli Cave (მაპელის მღვიმე); 42°38'22"N, 42°11'39"E; 330 m a.s.l.; 12 October 2019; J. Grego, L. Mumladze and G. Bananashvili leg.

Diagnosis.

The new species differs from the Kartvelobia sinuata sp. nov. by its very weakly sinuated almost straight labral margin, minute shell size, more pitted protoconch and different shape of the aperture. From the similar sized K. kinchkha sp. nov. differs by its less sinuated labral margin, by less inflated whorls and by the pitted protoconch surface. Measurement comparison of Kartvelobia species is given in Table 4 .

Description.

Shell: minute, 1.32-1.45 mm high, elongated-oval shell with four whorls, semi-blunt apex and smooth whitish glossy surface; slightly inflated whorls separated by weak suture. Aperture irregularly tear-shaped, slightly expanded and detached from the body whorls by a distant grove or gap. Lateral profile of labral margin almost straight with very inconspicuous sinuation; columellar labral profile straight. Protoconch surface pitted.

Operculum: not known.

Animal body: not known.

Holotype measurements: H-1.45 mm; W-0.74 mm; BH-1.02 mm; BW-0.62 mm; AH-0.55 mm; AW-0.58 mm; CA: 51°.

Anatomy: not known.

Etymology.

Name after the type locality: the karst spring Shisha at southeast end of village Mukhuri.

Habitat.

Stygobiotic species. The empty shells of the species were washed out through the small spring lake after large water flow induced by heavy rains in May 2018. The deep spring Lake Shisha drains karstic waters from the nearby limestone massif, but likely gets a portion of its water directly from the surface through a nearby sinkhole (more opalescent water observed shortly after the heavy rain). The condition of the shells (few worn shells and many fragments) suggests its stygobiont habitat deeper than the spring head.

Distribution.

Only known from the type locality and from nearby Mapeli Cave in Mukhuri.

Conservation status.

The number of known locations (2) is no more than 5 and EOO is smaller than 20 km2. There is no reason to suppose that AOO, EOO, number of locations, number of subpopulations or the number or mature individuals are declining however due to its extremely small EOO we assessed as Vulnerable (VU) D2.

Remarks.

The second population from Mapeli Cave generally has a more elongate and conical shell with more inflated whorls. Its taxonomic position needs to be further investigated.

Figures

Plate 4. 1 - 4 Kartvelobia shishaensis sp. nov., Georgia, Samegrelo, Mukhuri, Shisha Spring 1 holotype 2 paratype 3, 4 K. kinchkha sp. nov., Imereti, Kinchkha, small travertine waterfall at right bank of Okatse below the large waterfall: 3 holotype 4 paratype 5, 6 K. sinuata sp. nov., Imereti, Kinchkhaperdi, spring along road to Askhi Plateau, dwarf population 7 K. sinuata sp. nov., Imereti, Satsiskvilo, Turchusmtha, paratype - typical form 8, 9 K. cf. shishaensis sp. nov., Georgia, Samegrelo, Mukhuri, Mapeli Cave. The numbers correspond to individuals, and the letters represent the different views of the same individual. Photograph J. Grego.