Zospeum dubokidoense Jochum & Ruthensteiner, 2024

Jochum, Adrienne, Michalik, Peter, Inäbnit, Thomas, Kneubühler, Jeannette, Slapnik, Rajko, Vrabec, Marko, Schilthuizen, Menno & Ruthensteiner, Bernhard, 2024, 3 D X-ray microscopy (Micro-CT) and SEM reveal Zospeum troglobalcanicum Absolon, 1916 and allied species from the Western Balkans (Ellobioidea: Carychiidae), European Journal of Taxonomy 926, pp. 1-62 : 30-32

Zospeum dubokidoense Jochum & Ruthensteiner sp. nov.

urn:lsid:zoobank.org:act:118E4771-C551-49E8-AAC1-371E5E279FFB

Figs 7D–F , 8G–L

Diagnosis

Shell ca 1.5 mm, conical, with 5–5¼ slightly shouldered whorls, punctuated by deep, irregular growth lines; aperture elliptical-ovate to subquadrate; parietal shield compact, positioned low on the body whorl; columella centrally aligned, moderately slender, attenuate; lamella loosely positioned under penultimate whorl succeeded by an incomplete middle lamella and a basal bulge above the umbilicus, forming a thick basal lamella; basal lamella extends out of the aperture as a low ridge on the columellar side of the parietal shield.

Etymology

This species is named after the type locality cave, Duboki do in western Montenegro.

Type material

Holotype

MONTENEGRO • Duboki do ; “potoček v dvorani, Mtg.” [a stream in the cave chamber, Montenegro]; depth - 60 m; [42.4949°N, 18.8106°E]; Aug.1975; F. Velkovrh leg.; MCSMNH-PMSL-Moll. - FVelkovrh 30360[spm1].

Paratypes

MONTENEGRO • 2 specs; same collection data as for holotype; MCSMNH-PMSL-Moll.- 30360 [spm2-3].

Description

MEASUREMENTS. Holotype: sh: 1.514 mm; sw: 1.088 mm; ah: 0.622 mm; aw: 0.642 mm; hlw: 0.921 mm; SA: 63.64 deg. Paratypes (N = 2): sh: 1.512 –1.546 mm; sw: 1.085 –1.103 mm; ah: 0.639 –0.663 mm; aw: 0.611 –0.645 mm; hlw: 0.961 –0.982 mm; SA: 65.73–68.83 deg.

Shell conical, height ca 1.5 mm with 5 convex shouldered whorls, punctuated by deep irregular growth lines; last half of final whorl coils tightly under penultimate whorl such that right side almost disappears under spire (apical view); aperture elliptical-ovate to subquadrate; peristome narrow on upper palatal side, pronounced notch present at upper junction with parietal shield, columellar side of peristome roundish-angular, callused, rim slightly reflected; rim recedes less than 1 / 6 width of penultimate whorl (aperture facing left view); parietal shield compact, thickly callused with a low straightish edge; columella centrally aligned, slender, attenuate; lamella loosely positioned under penultimate whorl followed by an incomplete weak middle lamella and a lamellar bulge above the umbilicus forming a blunt basal lamella; basal lamella extends out of the aperture as a low ridge on the columellar side of the parietal shield (umbilical view); umbilicus closed, no depression, region callused and puckered; columellar side of peristome callused and positioned straight at center with leftward tendency in relation to the umbilicus; alignment of last ¼ whorl compact.

Distribution

This species is only known from its type locality.

Remarks

This species is the closest to Z. intermedium Jochum & Ruthensteiner sp. nov. in that it has a lamella set deep in the shell, which is positioned high up on the columella, but differs in forming a short, very weak parietalis that runs out to less than half of the extension of the parietal shield (umbilical view). The base of the shell (umbilical view) is heavily puckered in Z. dubokidoense Jochum & Ruthensteiner sp. nov. and smooth in Z. intermedium . The shell dimensions are comparable except that the aperture height and the height of the last whorl is greater in Z. dubokidoense . The only other shell to show an elliptical ovate aperture and a reduced parietal shield is the deformed shell from Cetinska pećina, Cetinje, MCSMNHPMSL-Moll.-FVelkovrh 34099[spm4] ( Fig. 5 ).

According to the speleologist, László Dányi (pers. comm. May 2022), Duboki do cave is longer than 4.2 km and more than - 530 m deep. “It has many chambers and very different parts.”

Figures

Fig. 7. Lightmicroscopic images of shells from the caves Lipska pećina and Duboki do (Montenegro) with specimen labels. A–C. Zospeum troglobalcanicum Absolon, 1916 (MCSMNH-PMSL-Moll.-FVelkovrh 29603). D–F. Zospeum dubokidoense Jochum & Ruthensteiner sp. nov. D. Holotype (MCSMNH- PMSL-Moll.-FVelkovrh 30360[spm1]). E–F. Paratypes, Duboki do, Montenegro (MCSMNH-PMSL- Moll.-FVelkovrh 30360[spm2-3]).

Fig. 8. 3D visualizations of Micro-CT data of shells from the caves Lipska pećina and Duboki do (Montenegro). A–F. Zospeum troglobalcanicum Absolon, 1916 (MCSMNH-PMSL-Moll.-FVelkovrh 29603) (Fig. 7A). A. Aperture view. B. Aperture facing right view. C. Apical view. D. Dorsal view. E. Aperture facing left view. F. Ventral view showing reduced umbilical depression. G–L. Zospeum dubokidoense Jochum & Ruthensteiner sp. nov., holotype (MCSMNH-PMSL-Moll.-FVelkovrh 30360[spm1]). G. Aperture view. H. Aperture facing right view. I. Apical view. J. Dorsal view. K. Aperture facing left view. L. Ventral view showing no umbilical depression.

Fig. 5. 3D visualizations of Micro-CT data of the deformed shell, (MCSMNH-PMSL-Moll.-FVelkovrh 34099[spm4]) from Cetinska pećina. A. Aperture view. B. Aperture facing right view. C. Apical view. D. Dorsal view. E. Aperture facing left view. F. Ventral view with umbilicus covered by last quarter of shell whorl.