Virpazaria (Virpazaria) pageti kleteckii Štamol & Subai in Reischütz et al., 2012

Virpazaria pageti kleteckii Štamol & Subai in Reischütz et al., 2012: 32, fig. 2.

Diagnosis

Distinguished from nominate form by smaller, non-detached aperture, which is less covered by parietal flap in frontal view.

Material examined

Holotype

CROATIA • Konavle Region, Gruda, Vilina Cave; UTM: BN81; 6 Apr. 2010; R. Ozimec leg.; CNHM 10393.

Paratypes

CROATIA • 2 spec.; same collection data as for holotype; Croatian Biospeleological Society collection [not seen] • 1 spec.; in Dubravka village, ca 5 km NE of Gruda; Mar. 2011; A. and P.L. Reischütz leg.; Reischütz private collection [not seen].

Dimensions

H 1.5–1.65 mm; W 2.75–3.0 mm.

Distribution and remarks

This species (including its subspecies) has a restricted range north of Kotor Bay in Croatia and Montenegro (Gittenberger 1969; Reischütz et al. 2012). The type lot of the nominate form was collected from debris at the mouth of the Sutorina River. Later, this species was found in rock crevices at the eastern side of Prevlaka Peninsula, between Njivice and Igalo very near the type locality (see Gittenberger 1988). At another point of the Prevlaka, ca 3.5 km as the crow flies from the former site, Reischütz et al. (2012) reported further shells of this species (four adults and 15 juveniles). They were distinguished from the nominate form by their smaller shell, finer and denser ribbing, smaller parietal flap, as well as the nondetached aperture, and were described as Virpazaria pageti alexanderi. In 2018, we were able to obtain a larger sample of V. p. alexanderi from the type locality that provided a good opportunity to study size extremes and the variability of character states within this population. In our sample (HNHM 104391), shell width ranged between 2.1 and 3.0 mm, shell height between 1.3 and 1.9 mm, number of whorls between 3¾ and 4¼, number of ribs on the last whorl between 48 and 83 and we found specimens with detached and non-detached apertures as well. The values and character states given by Gittenberger (1988) for the nominate form and those given by Reischütz et al. (2012) for V. p. alexanderi all fall within these ranges. This alone might be a good reason for treating them as synonyms, which is only reinforced once their geographical distribution is also taken into consideration. The two type localities are not only close to each other, but are located along the foot of the same limestone hill, which is composed of the same Upper Cretaceous geological formation. Having no geographical or geological barrier in between, it is likely that the two sites contain the same subterranean population and an extensive sampling along the Prevlaka Peninsula might detect this species at further locations.

Virpazaria pageti kleteckii was found at two locations somewhat north of the Prevlaka; namely at Vilina Spilja near Gruda and at Dubravka ca 5 km NE of Gruda. The original description was based on four specimens only (three from Vilina Spilja and one from Dubravka). Until further available material makes it possible to test the stability of distinguishing features, V. p. kleteckii must be accepted as a distinct subspecies.