Genus Travunijana Grego & Glöer, 2019

Until now, this recently described genus was recognised only from the type locality of its type species (Vrelo “Goricki Studenac” in Gorica near Trebinje). However, closer investigation of the protoconch structure as well as of the general shell morphology supported the transferral of several species formerly assigned to Plagigeyeria to the genus Travunijana .

Differential diagnosis

The genus Travunijana can be clearly distinguished from the genus Plagigeyeria by its overall pitted surface sculpture of the protoconch without any spiral cords. Plagigeyeria has a faintly malleated and radially structured protoconch with spiral cords, malleated or granulated inter-rib spaces without a pitted surface. Furthermore, the shells of Travunijana are more solid with no flaring and less expanded apertures and with straight lateral labral profile and a characteristic smooth sinuation at the columellar margin. The lateral labral profile of Plagigeyeria is mostly sinuated, especially around the anterior and posterior canals and the part of the columellar margin adjacent to columella is straight or weakly sinuated. The peristome of Plagigeyeria is more reflexed and more widely expanded. The shell surface of Travunijana is lacking the inter-rib axially malleated surface structures of Plagigeyeria . The genus Belgrandia Bourguignat, 1870 with its Balkan representatives has also a pitted protoconch, however the present pitting is deeper and coarser than that of Travunijana . The genus Belgrandia can be distinguished by a distinct callous varix at the labrum or at the labral part of the body whorl.

Anatomy

The anatomy of the male genitals of the type species is described by Grego & Glöer (2019) (p. 88: fig. 6).

Distribution

The genus Travunijana is known from the karst regions adjacent to the South Dalmatian coastline from Gradac and Ploče to Dubrovnik, and about 32 km inland from the Adriatic coastline to Prolog, Vrgorac, Svitava, Veličani and to Trebinje. Further northwards its distribution is known from Trebinje to Bileća and towards Gatačko Polje and Dabarsko Polje to Vrelo “Bunica” in Hodbina (Fig. 19). The distribution ranges of Travunijana and Plagigeyeria overlap only in the area of Hodbina, Dabarsko Polje and north of Trebinje, where both genera could occur sympatrically.

Type species

Travunijana vruljakensis Grego & Glöer, 2019, holotype HNHM MOLL 104416.

Other taxa assigned to the genus

Plagigeyeria ovalis Kuščer, 1933, Plagigeyeria robusta Schütt, 1959, Plagigeyeria robusta asculpta Schütt, 1972, Plagigeyeria klemmi Schütt, 1961, Plagigeyeria nitida Schütt, 1963, Plagigeyeria angelovi Schütt, 1972, Plagigeyeria edlaueri Schütt, 1961, Plagigeyeria tribunicae Schütt, 1963 and Travunijana gloeri sp. nov.