Vitrea gostelii, Gümüş & Neubert, 2012

Guemues, Burcin Askim & Neubert, Eike, 2012, New taxa of terrestrial molluscs from Turkey (Gastropoda, Pristilomatidae, Enidae, Hygromiidae, Helicidae), ZooKeys 171, pp. 17-37 : 18

Vitrea gostelii sp. n. Fig. 1

Type specimens.

Holotype NMBE 23972. Type locality: Antalya Ili, Kaş, Valley of the Eşen Çayı, Palamut, 36.4088°N, 29.3644°E, 350 m alt., limestone rocks, 10 km S of Saklıkent, 06.06.2006.

Diagnosis.

A small species of Vitrea with a spiral sculpture of small threads and faint riblets crossing the spirals.

Description.

The shell colour is pale whitish, with a broadly depressed spire. The protoconch is broadly enlarged and sculptured by fine spiral threads. The whorls of the teleoconch are narrow and increase regularly, suture of medium depth. The last whorl is broadened, non-descending, well rounded. The surface of the teleoconch is sculptured by fine widely spaced riblets. The spiral sculpture of the protoconch continues on the teleoconch whorls and becomes stronger, dissecting the riblets and giving them a fine granulated appearance. On the subsurface, the riblets become faint while the spiral sculpture increases in strength.

The umbilicus is of medium width and funnel-shaped to cylindriform.

Measurements.

Holotype: H = 1.29; D = 2.25; PH = not measured because of damage of shell; PD = 1.05; W = 4.75.

Distribution

( Fig. 29 ): Hitherto, only the holotype is known from the type locality in the Kaş area.

Etymology.

This new species is dedicated to our dear friend, the late Dr. Margret Gosteli from the Natural History Museum Berne, Switzerland. She very much enjoyed our joint visit to Turkey in 2006 and was eager to work about the malacofauna of Turkey.

Remark and differential diagnosis.

The confinement of this undoubtedly new species to a pulmonate family is not easy, because only a single, dead collected shell is available. Although it looks somewhat similar to species from the family Punctidae (with Punctum pygmaeum (Draparnaud, 1801) known from Turkey), we have decided to place it in Pristilomatidae because of the pale color of the shell.

Under a conchological point of view, a classification within the pristilomatid genus Lindbergia Riedel, 1959, would also be possible, as the two genera can only be differentiated by the anatomy of their genital organs ( Riedel 1959, 1960). We here confine this species to the genus Vitrea Fitzinger, 1833, because of its overall conchological resemblance to other species comprised in this genus. An assignment to Oxychilus Fitzinger is less probable, as even the smallest species of Oxychilus are clearly larger than the new species.

Vitrea gostelii sp. n. differs from all Vitrea species known from Turkey by the presences of riblets and a spiral sculpture. It somewhat resembles Vitrea riedeliana , but the spire in Vitrea riedeliana is more elevated. Vitrea riedeli has a smooth shell with a wider umbilicus with a deeper suture.

This species was found during our survey in 2006 below a large limestone rock face of probably about 50 m of height. Probably, this species lives subterraneously, and a more targeted search in the accumulated soil of carstic crevices will yield some living specimens, which then will help to corroborate the taxonomic position of this new species.

Figures

Figure 1. Vitrea gostelii sp. n., D = 2.25 mm. - All figures scaled x 20, phot H. Baur, NMBE.

Figure 29. Distribution map. ▲ Vitrea gostelii sp. n. ● Turanena demirsoyi sp. n. and Rhabdoena gostelii sp. n. ■ Euchondrus paucidentatus sp. n. ▼ Metafruticicola kizildagensis sp. n. ► Assyriella thospitis menkhorsti ssp. n.