Gyraulus elenae, Vinarski, Glöer & Palatov, 2013

Vinarski, Maxim V., Glöer, Peter & Palatov, Dmitry M., 2013, Gyraulus elenae sp. n. — a new Planorbid snail from Eastern Turkey (Mollusca: Gastropoda: Planorbidae), Zootaxa 3664 (1), pp. 95-98 : 95-97

Gyraulus elenae sp. n.

( Fig. 1 , 2 ; Table 1 )

Type locality: Eastern Turkey, Rize Province, Findikli District , a spring in the valley of the Chaglayan (Çaġlayan) River . 41°11'13.80" N, 41°19'3.59" E. The spring is situated nearly 19–20 km above the mouth of the Chaglayan River.

Material studied. Type series (holotype and 2 paratypes) is kept in ZMH ( holotype: ZMH 79657 ; paratypes: ZMH 79658 ). Another paratypes are in the collections of ZIN (5 ex), MSAM 14-1278 (2 ex) and collection of P. Glöer (1 ex).

Shell description. Shell small (1.75–2.6 mm width), periostracum color is yellowish brown or dark brown, consists of 2.5–3.5 (2.77 in average) rounded whorls. Keel or peripheric angle are absent. The first whorls are flat (not immersed), the basal side is wide, deep umbilicated, the first whorl is clearly visible through the umbilicus. The surface if finely striated and glossy. The aperture is broad and slightly deflected, its height is nearly 0.75 of its width (limits 0.65–0.83, average 0.74). The body whorl is relatively high (0.25–0.30 of the shell diameter) and wide, its width may reach 0.8–1.0 mm.

Soft body. Head, foot and mantle of the animal are dark gray without any characteristic pattern of coloration.

Anatomical traits. The praeputium and the penis sheath are of nearly same length (see Fig. 1 ). The former is visibly wider and somewhat inflated in the proximal end. The penis sheath is narrow and oblong. The bursa copulatrix is club elongated with a short bursa duct. The prostate gland bears eight long finger-shaped diverticles.

Differential diagnosis. It is the smallest species of Gyraulus of the Near East region and Caucasus. Besides, it is the only species in which the initial whorls are not immersed and the umbilicus is so wide that the first whorl is visible through it. More information on diagnostic traits of G. elenae sp.n. and related species is given below in the identification key.

Distribution. The species is known from the type locality and two other spring situated in closer proximity to the latter with coordinates 41°11'17.13" N, 41°18'41.49" E (see Fig. 2 ). Most probably, it will be found in adjacent districts of Georgia and other part of Turkey.

Ecology. The species inhabits shallow springs where it is recorded alongside with snails Belgrandiella adsharica (Lindholm, 1913) and other representatives of freshwater crenobiotic fauna. The locus typicus is situated within a filbert garden (with alder-trees). The second spring is in the beech forest, whereas the third one is situated in a beechrhododendron forest. Water vegetation was represented by mosses predominantly with rare cardamine plants. The snails were collected on hard substrates under water temperatures 13–14º C and flow velocity 0.1 m/sec and lower. G. elenae sp.n. has been registered at 700–1000 m altitudes.

Etymology. The species is named in honor of Dr. Elena V. Soldatenko (Smolensk, Russia), who made a significant contribution to the planorbid snails taxonomy.

Figures

FIGURE 1. Gyraulus elenae sp. n. The holotype. Shell and copulative apparatus. Abbreviations: pht—penis sheath; prp — praeputium; vd—vas deferens.

FIGURE 2. A map showing localities of G. elenae in Eastern Turkey.