Travunijana robusta asculpta (Schütt, 1972)

Grego, Jozef, 2020, Revision of the stygobiont gastropod genera Plagigeyeria Tomlin, 1930 and Travunijana Grego & Glöer, 2019 (Mollusca; Gastropoda; Moitessieriidae and Hydrobiidae) in Hercegovina and adjacent regions, European Journal of Taxonomy 691, pp. 1-56 : 43-44

Travunijana robusta asculpta (Schütt, 1972) comb. nov.

Figs 7N , 15C

Plagigeyeria robusta asculpta Schütt, 1972: 115 , 122, pl. 8, figs 25–26.

Plagigeyeria robusta asculpta – Bole & Velkovrh 1986: 202. — Bank 2013: Fauna Europaea v. 2.6. — Bank & Neubert 2017: 25.

Diagnosis

Shell very similar to nominotypical subspecies but having in general a more elevated, more conical spire with blunter apex. Surface can be smooth or finely ribbed as well as in the nominotypical morphotype. Aperture ear-shaped and missing the slightly protruded columellar fold of the nominotypical subspecies. Lateral labral profile straight and columellar labrum possesses a weak cut sinuation. Protoconch surface pitted.

Distribution

Travunijana robusta asculpta can be found in the thanatocoenoses of the Vrelo “Ombla” near Komolac (7 m a.s.l.) and Vrelo “Mlin” (2 m a.s.l.) at Mali Zaton north of Dubrovnik. Springs are draining the karst area of upper-to-central Popovo Polje (227 m a.s.l).

Remarks

The morphological variability of nominotypical subspecies and T. robusta asculpta overlap significantly and even Schütt (2000) assigned some of specimens of P. robusta asculpta from the type locality (Vrelo “Ombla”) to the nominotypical subspecies based upon the presence of ribs, and conversely, the few specimens collected from Trebišnjica Springs in Bileća were assigned to T. robusta asculpta just for their lack of ribs. However the presence or absence of the fine shell ribs on the eroded shells found in the thanatocoenoses has to be carefully evaluated by their remains around the suture, as upon first sight both ribbed and smooth forms can be found in the thanatocoenoses within the springs draining the whole Eastern Trebišnjica aquifer. The main distinguishing feature of T. robusta asculpta is in general the more elevated and more conical spire and slightly more elongated shell shape, but even this feature possesses a high variability within each locality. Until live material becomes available and larger shells material can be examined, I prefer to separate both in a provisional way on a subspecies level, based only on their zoogeographical data. It is possible that further investigation could reveal several related species in the T. robusta complex.

Figures

Fig. 7 (next page). A. Plagigeyeria mostarensis, Kuščer 1933, holotype, from Kuščer 1933, assigned to Izvor Buna in Blagaj but rather represents the form from near spring Bunica in Hodbina. B. P. mostarensis, hypotype of Schütt, 1970, from spring Bunica (SMF 221236). C. P. mostarensis, likely topotype from spring Bunica (JG F1146). D–E. P. mostarensis var., from spring of Buna assigned as type locality (JG F0536). Fa–Fb. Paladilhiopsis (Costellina) turrita (Kuščer, 1933) paratype and holotype from Kuščer 1933, spring Izvor in valley of river Jadro near Split. G. P. pseudocostellina sp. nov., left bank side spring of river Buna 400 m from main spring (holotype HNHM-MOLL-104164). H. P. pseudocostellina sp. nov., left bank side spring of river Buna 200 m from main spring (paratype JG F1140). I. Travunijana ovalis (Kuščer, 1933), holotype from Kuščer, assigned to Izvor Buna in Blagaj but not found in assigned locality, only in spring Bunica in Hodbina. J–K. T. ovalis (Kuščer, 1933), spring Bunica near Hodbina (JG F1145). L. T. robusta (Schütt, 1959), Trebinje district, Tučevac spring at right bank of Trebišnjica River (JG F1163). M. T. robusta, Trebinje district, Gorica, cave Vruljak 1 (JG F0831). N. T. robusta asculpta (Schütt, 1972), spring Ombla (Dubrovačka Rijeka) at Komolac near Dubrovnik (JG F1080).

Fig. 15. A. Travunijana robusta (Schütt, 1959), Trebinje, IzvorTučevac, SBMNH 626406. B. Travunijana robusta (Schütt, 1959), Trebinje, Vrelo Vruljak 1, SBMNH 625919. C. Travunijana robusta asculpta (Schütt, 1972), Croatia, Dubrovnik, Komolac, Izvor Ombla, SBMNH 625896. D. Travunijana gloeri sp. nov., Bjeljani, Dabarsko Polje, Vrelo Vrijeka, paratype SBMNH 632722. Scale bars = 1mm. (SEM SBMNH Vanessa Delnavaz).