Clausilioides berendinae, Ruud, A. Bank, Henk P. M. G Menkhorst & Eike Neubert, 2016

Ruud, A. Bank, Henk P. M. G Menkhorst & Eike Neubert, 2016, Descriptions of new and little-known land snail taxa from Turkey, and establishment of a new genus (Gastropoda, Pulmonata: Lauriidae, Enidae and Vitrinidae), Basteria 80 (1), pp. 5-30 : 17-19

Clausilioides berendinae spec. nov. ( Fig. 10)

Clausilioides biplicatus – Schütt, 2001: figure on page 122 (“Artvin“).

Clausilioides spec. – Páll-Gergely, 2009: 73, fig. 4 (castle of Ardanuç).

Clausilioides biplicatus – Schütt, 2010: figure on page 121 (Ardanuç).

Type locality & type material. – Turkey, Vilayet Artvin, 1 km W. Ardanuç, 500 m (41.1278°N 42.0606°E), H.P.M.G. Menkhorst leg., 7.vii.1986. Holotype NMBE 544672/1 , paratypes HMK/47, RBA/3, RMNH/3, ZMH/3.

Diagnosis. – A medium-sized, highly elongated fusiform Clausilioides species with a prominent parietal callus and a deeply situated palatal fold that reaches the penultimate whorl.

Description. – Shell dextral, highly elongated fusiform in outline, with a very narrow to about closed, slit-like, umbilicus. The 11.0-11.5 whorls are slightly convex with a shallow suture; the last 1-2 whorls are more flattened. Teleoconch with irregular, fine, oblique striae; there are no spiral striae. Shell rather thin, partially translucent, glossy, uniformly corneous to dark-brown coloured, with a whitish band behind the peristome. Aperture oval to more rounded, horny yellowish on the inside. Peristome well reflected and well thickened by a labial callus (which is often slightly coloured), the columellar and palatal insertion connected by a strongly developed parietal callus which is thick and frequently cylindrical in shape. The parietal callus is even more swollen at both ends; at the palatal end it generates a subangularis , which is connected with the palatal insertion of the peristome by a weakly developed callus. There is a broad, indistinct thickening at the peristome at the position of the palatalis superior. The curled columellar ledge is well developed and reaches to about halfway of the columellar side of the aperture. The last whorl is constricted, thereby contributing to the fusiform shape of the shell. There is a palatal fold deep inside the last whorl (it mostly cannot been seen in the aperture) which is visible through the shell as a well-delineated whitish band; it mostly reaches towards the insertion of the palatal peristome, and can further extend into the end of the penultimate whorl.

Measurements (n = 14). – H = 14.2-17.0 (mean

15.4); LWM = 5.3-5.9 (mean 5.6); HM = 3.1-3.5 (mean 3.4); LWD = 2.6-3.4 (mean 2.9); LWM = 2.8-3.2 (mean 3.1); MD = 2.4-2.6 (mean 2.6); NW = 10.2-12.1 (mean 11.3). For comparison, measurements are here given for C. biplicatus (n = 6; collected 5 km NW Artvin, Menkhorst leg.): H 18.8-20.7 (mean 19.7); LWH 7.2-8.0 (mean 7.7); HM 4.2-4.8 (mean 4.5); LWD 3.9-4.4 (mean All photographs Bochud & Neubert, × 8.

4.1); LWM 4.1-4.5 (mean 4.3); MD 3.3-3.7 (mean 3.5); NW 11.0-11.5 (mean 11.3).

Localities. – Vilayet Artvin: type locality (see above); Ardanuç, castle (41.1273°N 42.0549°E) (HMK/15+17; RBA/1; Páll-Gergely, 2009: 73); Ardanuç, 4.9 km towards Yalnızçam Geçidi (41.1009°N 42.1058°E) (HMK/32; RBA/2); Ardanuç, 7 km towards Yalnızçam Geçidi (41.0960°N 42.1154°E) (HMK/23); Ardanuç, 10.2 km towards Yalnızçam Geçidi (41.0814°N 42.1433°E) (HMK/14); 0.5 km W. Ardanuç (41.1241°N 42.0605°E) (HMK/80; RBA/4); 1.5 km NW. Ardanuç (41.1297°N 42.0615°E) (HMK/36); 2 km NW. Ardanuç (41.1298°N 42.0584°E) (HMK/43; RBA/3); 4 km NW. Ardanuç (41.1365°N 42.04267°E) (HMK/2; NMBE 544673/5); 5 km NW. Ardanuç (41.1359°N 42.0334°E) (HMK/27; NMBE 544674/3); 6 km NW. Ardanuç (41.1383°N 42.0248°E) (NMBE 544675/2).

Derivatio nominis. – Named after Maria Berendina van der Ende (24.viii.1958), for encouraging one of the authors (Ruud Bank) over a period of more than 30 years.

Differentiation. – The geographically nearby C. biplicatus differs from C. berendinae by its larger dimensions, the less convex whorls, the generally less well-developed parietal callus, the moure rounded aperture, the less slender apex and the less con- stricted last whorl. Finally, the palatal fold is situated less deep in the last whorl (its start can be seen deep in the aperture), and reaches often only to the insertion of the columellar peristome or in between the insertion of the columellar and palatal peristome; it never enters the penultimate whorl.

Remarks. – Clausilioides berendinae is a species that is common in the surroundings of Ardanuç (east of Artvin). It has been confused with C. biplicatus , which lives in a restricted area near Artvin. The shell depicted by Schütt (2010: 121) as C. biplicatus from Ardanuç is in fact C. berendinae . The same is the case with the shell depicted by Schütt (2001: 122); the given locality "Artvin" is with certainty imprecise. On the other hand, the shell depicted by Schileyko (1998b: 233 fig. 286A) is indeed C. biplicatus (its size is 20.0 x 4.2 mm), as is the drawing of the genital organs given by Hesse (1933: 205-206, fig. 35). The holotype of biplicatus has been figured by Zilch (1959: 185 fig. 637). The anatomy of C. berendinae has been briefly touched upon by Páll-Gergely (2009: 73, fig. 4 – as “an undescribed species of Clausilioides “).