Virpazaria (Virpazaria) gittenbergeri Fehér & Deli & Erőss & Lika 2019, sp. nov.

Virpazaria (Virpazaria) gittenbergeri Fehér & Erőss sp. nov.

urn:lsid:zoobank.org:act: C987B11A-418B-48B2-A5D5-B71966765600

Fig. 4 A–E

Spelaeodiscus sp. (juv.) – Subai 2009: 111.

Differential diagnosis

This species can be distinguished from congeners by its small size and by its having one knob on the palatal peristome, and from species of the related Spelaeodiscus, which have one knob/tooth on the peristome by its inferiorly broader rounded body whorl and narrower aperture.

Etymology

This species is dedicated to and named after Edmund Gittenberger (Leiden, the Netherlands), a prominent malacologist who did pioneering work on the subterranean terrestrial gastropods of the Balkans. The name is used as the genitive of a noun of male gender.

Material examined

Holotype

MONTENEGRO • Rumija Mts, 2 km S of Štegvaš Pass on Ostros–Ulcinj road (4 km S of Arbnež); 42.0582° N, 19.3535° E; 350 m alt.; 28 May 2015; T. Deli, Z. Erőss and Z. Fehér leg.; HNHM 103411.

Paratypes

MONTENEGRO • 20 spec.; same collection data as for holotype; HNHM 103413 • 20 spec.; same collection data as for holotype; NHMW 111671 • 20 spec., 38 fr.; same collection data as for holotype; DT • 8 ad., 8 juv.; same locality as for holotype; 16 Jul. 2017; Z. Erőss and Z. Fehér leg.; HNHM 103451 • 8 ad., 9 juv.; same locality as for holotype; 16 Jul. 2017; Z. Erőss and Z. Fehér leg.; NHMW 111674 • 16 ad., 9 juv.; same locality as for holotype; 16 Jul. 2017; Z. Erőss and Z. Fehér leg.; ER • 2 ad., 1 juv.; SW of Štegvaš Pass, 2 km S of Arbnež on Ostros–Ulcinj road; 42.0636° N, 19.3710° E; 480 m alt.; 16 Jul. 2017; Z. Erőss and Z. Fehér leg.; HNHM 103445 • 3 ad., 1 juv.; same collection data as for preceding; NHMW 111673 • 3 ad., 1 juv.; same collection data as for preceding; ER.

Other material

ALBANIA • Shkodër district, Mt Tarabosh, Vallas, near mosque; 42.0506° N, 19.4162° E; 190 m alt.; 27 May 2015; T. Deli, Z. Erőss and Z. Fehér leg.; HNHM 103415 • same collection data as for preceding; NHMW 110430/MN/0986 • same collection data as for preceding; DT.

Dimensions

Holotype: H 1.55 mm; W 2.5 mm; Ha 1.0 mm; Wa 1.1 mm. Paratypes (HNHM 103413, n =5): H 1.4–1.6 mm; W 2.35–2.5 mm. Vallas population (HNHM 103415, n= 5): H 1.25–1.5 mm; W 2.2–2.4 mm.

Description

Shell discoid, spire barely raised, consists of 4¼–4¾ regularly increasing whorls, of which 1½–2 are protoconch whorls. Fresh shells glassy translucent, older shells whitish. Protoconch grained. Teleoconch whorls equidistantly ribbed: 59–69 ribs on body whorl and fine, regular lines in between.

In bottom view, umbilicus wide, 1/4–1/5 of total shell width, a small part of it overlaid by columellar part of aperture. In frontal view, silhouette of body whorl asymmetrically rounded (shouldered): broader curved in bottom, more angulated on upper side and near suture horizontally flattened. Suture barely depressed.Aperture narrow crescent-shaped. Instead of a flap, with an outstretched swelling (a thickened and emerged callus) on parietal side. One knob on palatal peristome, ca at one-third of way between its angular and columellar junctions. Peristome somewhat reflected between columellar junction and palatal knob, appearing thickened in frontal view. Above knob, peristome simple, delineating an apertural sinus. In side view, parietal swelling oblique (inferior part stands forward) and aperture sigmoidally inclined (inferior part stands backward).

Distribution

This species is known from the southeastern part of the Rumija Mts (also known as Mt Tarabosh). The Štegvaš Pass (Montenegro) and Vallas (Albania) populations are within a distance of 5 km of one another. Both sites are on Upper–Middle Triassic limestone. At the type locality, this species was found together with V. stojaspali and V. pesici.

Conservation status

To our present knowledge, this is a narrow-range endemic species with an area of occurrence (AOO) smaller than 20 km 2. However, there is no reason to suppose that AOO, extent of occurrence (EOO), number of locations, number of subpopulations or the number of mature individuals are declining or extremely fluctuating. Therefore, it might be assessed as Near Threatened (NT).

Remarks

The Vallas population differs from the typical form by its denser ribbing (76–88 ribs on the body whorl).