Zospeum kolbae Jochum, Inäbnit, Kneubühler & 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 : 44-46

Zospeum kolbae Jochum, Inäbnit, Kneubühler & Ruthensteiner sp. nov.

urn:lsid:zoobank.org:act:02B1232B-1BC5-404A-8F6D-FD189619B3AA

Figs 16 , 22C

Diagnosis

Shell 1.38–1.52 mm, conical with 4.5–5 flatly convex, regular, tightly coiled whorls; aperture elliptical-ovate to subquadrate-oblique; columellar side of peristome thickly callused; teleoconch sculpture with conspicuous irregular scratch-like growth lines and milky, horizontal banding on the penultimate and body whorls.

Etymology

This species is named in honour of Prof. Dr.Annette Klussmann-Kolb for providing valuable mentorship and introducing AJ to the Ellobioidea .

Type material

Holotype

MONTENEGRO • [holotype and body destroyed for DNA extraction, photograph and DNA are the only remnants of the holotype]; Njeguši, St John’s cave ; 42.4307° N, 18.8115° E, 915 m a.s.l.; ca - 85 m vertical depth below the cave entrance; 5 Aug. 2021; László Dányi & Nikolett Ujhegyi leg.; GenBank CO1 gene: ON037484; GenBank 16S gene: ON041449; GenBank H3 gene: ON088652; imaged shell of aliquot NMBE 571122 .

Paratype

MONTENEGRO • 1 spec. [paratype and body destroyed for DNA extraction, photograph and DNA are the only remnants of the paratype]; same collection data as for holotype; GenBank CO1 gene: ON037485; GenBank 16S gene: ON041450; GenBank H3 gene: ON088653; imaged shell of aliquot NMBE 571123 .

Description

MEASUREMENTS. Snails processed for DNA sequence data and thus, the type series has been destroyed. Holotype: sh: 1.38 mm; sw: 1.00 mm; ah: 0.66 mm; aw: 0.59 mm; hlw: 0.96 mm; SA: 75.69 deg.; NMBE 571122 ( Fig. 16A ). Paratype: (N = 1): sh: 1.59 mm; sw: 0.95 mm; ah: 0.73 mm; aw: 0.62 mm; hlw: 0.73mm; SA: 62.88 deg.; NMBE 571123 ( Fig. 16B ).

Shell 1.38–1.59 mm, conical; transparent; with 4.5–5 flatly convex, regular, tightly coiled whorls; penultimate whorl equal or slightly over ½ height of body whorl (in lateral view); aperture elliptical-ovate to subquadrate; columellar side long; suture shallow; teleoconch sculpture with conspicuous irregular scratch-like growth lines and milky, horizontal banding on the penultimate and body whorls; some weak axial ribbing present immediately behind palatal lip; palatal lip narrowly reflected, palatal-basal side reflected; peristome thickly callused on basal columellar side; parietal shield long and straight with conspicuous narrow notch indentation at upper parietal and palatal junction.

Distribution

This species is only known from the type locality, St John’s cave, in Njeguši, Montenegro.

Remarks

The two shells demonstrate a significant range in shell height (1.39–1.59 mm), constituting what might be the ends of the size spectrum for Z. kolbae Jochum, Inäbnit, Kneubühler & Ruthensteiner sp. nov. or that shell B is a potential hybrid with Z. dubokidoense Jochum & Ruthensteiner sp. nov. or a potential freak. Of all the shells in this study, shell B is by far the largest with that of one shell from Z. dubokidoense measuring a close second in shell height (1.546 mm). With its molecularly closest congener, Z. simplex , (1.41– 1.40 mm) it is comparable at the lower end of the size range but demonstrates a much broader spire angle than that of the narrower Z. simplex and a markedly larger aperture (ah) compared to that of Z. simplex . The elliptical-ovate to subquadrate shape of the aperture, the height of the penultimate whorl equaling or extending slightly over ½ the height of the body whorl (lateral view) are reminiscent of Z. dubokidoense from Duboki do cave ( Figs 6D , 7G ) (MCSMNHPMSL-Moll.-FVelkovrh 30360[spm1]). Their affinity in conjunction with the recent discovery of a connection between St John’s cave and Duboki do cave ( Csepreghy & Lenkei 2021) may be clarified by future sampling opportunities and DNA sequence analysis. Imaged with Z. kolbae , is an undescribed species ( Zospeum sp. 1 ) ( Fig. 16C–E ) (NMBE 577052–577053) found in the same cave chamber with two adults showing a substantially smaller size (1.29–130 mm) than that of Z. kolbae . A third, subfossil species, found in the dry part of the same cave, Z. njegusiense Jochum & Ruthensteiner sp. nov. ( Fig. 17 ) measures within the same size range as the two shells of Z. kolbae but shows no other affinity with it.

Type locality

According to the collector, László Dányi, “The small chamber, where all the snails were collected, is really a rather dry part of the cave, a so called ‘fossil’ part which doesn’t have any active water-flow – even temporarily – since ages. However, on the rocks there is a thin layer of clay which is wet around micro fissures because of percolating water.” ( Fig. 22B ). Maximum depth of St John’s cave is - 537 m (László Dányi pers. comm May 2022). Recent exploration by the Hungarian Speleo Camp detected a connection between St John’s cave and Duboki do cave ( Csepreghy & Lenkei 2021).

Figures

Fig. 16. Light microscopic images of full-bodied Zospeum Bourguignat, 1856 from Njeguši, St John’s cave. A–B. Zospeum kolbae Jochum, Inäbnit, Kneubühler & Ruthensteiner sp. nov. (NMBE 571122– 571123), individuals assessed by DNA sequencing with sigmoid intestine showing through shells (shells were destroyed post imaging for tissue extraction). A. Holotype (NMBE 571122), shell of aliquot, aperture, and aperture facing left view. B. Paratype (NMBE 571123), shell of aliquot, aperture, and aperture facing left view. C. Undescribed Zospeum sp. 1 (NMBE 577052) showing all perspectives. D–E. Undescribed Zospeum sp. 1 (NMBE 577053/2) showing all perspectives.

Fig. 22. Sites of localities and collections. A. Site of type locality of Zospeum njunjicae Jochum, Schilthuizen & Ruthensteiner sp. nov., Golubova pećina, Gornja Seoca, Montenegro. Credit: I. Njunjić. B. Collection site within St John’s cave, type locality of Z. kolbae Jochum, Inäbnit, Kneubühler & Ruthensteiner sp. nov. and Z. njegusiense Jochum & Ruthensteiner sp. nov., Njeguši, Montenegro (42.4307° N, 18.8115° E) with speleologist, P. Kunisch. Credit: Péter Lenkei. C. Entrance to Golubova pećina (42.2093° N, 19.1306° E), Gornja Seoca, Montenegro. Credit: I. Njunjić.

Fig. 6. Zospeum intermedium Jochum & Ruthensteiner sp. nov. (RMNH.MOL.234132) from Gittenberger (1975). A. Light microscopic images of apertural and dorsal views. B. Sample labels. C–H. 3D visualizations of X-ray Micro-CT data. C. Aperture view. D. Aperture facing right view. E. Apical view. F. Dorsal view. G. Aperture facing right view. H. Umbilical view showing slight umbilical depression and lamella projecting from the columellar side.

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. 17. Z. njegusiense Jochum & Ruthensteiner sp. nov., Scanning Electron Microscopy images. A. Holotype (NMBE 572639), aperture view showing subfossil shell with superficial erosion of shell layer. B. Paratype (NMBE 578378), aperture view showing close up of lamellar band on columella (Fig. C). C. Paratype (NMBE 578378), aperture view showing damaged shell and columella. D. Close up view of holotype (NMBE 572639), showing body whorl with low, irregular growth lines. E. Paratype (NMBE 578378), protoconch.