Two new freshwater mollusk species of the genus Graecoanatolica Radoman , 1973 from Turkey ( Gastropoda : Hydrobiidae )

Two species of the hydrobiid genus Graecoanatolica Radoman, 1973 were described from Turkey as new to science. The new species are characterized by a larger dimension of the shell. A comparative table of shell dimensions and features of penes to the species known for Turkey are provided. The total number of species of genus Graecoanatolica tallies now 12 species.

Graecoanatolica Radoman, 1973, is an endemic genus for Balkan (Macedonia and Greece) and Turkey, characterized at the first line by the conic (sensu Hershler & Ponder 1998: p. 6, Fig. 1f) shell.This genus originally was described by Radoman (1973), with Hydrobia vegorriticola Schutt 1962, as the type species.In addition to the two species known from the Balkans, i.e.Graecoanatolica vegorriticola Schütt, 1962 (Lake Vegoritis, Greece) and G. macedonica Radoman & Stankovic, 1979 (Dojran Lake, Macedonia), the latter has been declared extinct (Ryan & Griffith 2001, Albrecht et al. 2006, 2013), eight species of the genus have been reported from Turkey (Kebapçı et al. 2012).Most of these species occur in the Lakes Region of Turkey (Kebapçı et al. 2012), and with exception of Graecoanatolica lacustristurca and G. tenuis, they are restricted to a small distribution areas from which some of them were described only by shell features (Schütt 1962;Kebapçı et al. 2012); two of these species (G.brevis and G. conica) are declared as extinct (Kebapçı et al. 2012).
Some studies showed that hydrobiid genera can be distinguished among their congeners by combining the description of anatomical structures, in first line morphology of the penis, but also the female sex tract, with the morphology of the shell (Delicado et al. 2015).The species of the genus Graecoanatolica are uniform in their female sex tract, and characterized by the absence of receptacula.Based on the shell

Research Article
characters and features of penis, taxonomic status of the species of the genus Graecoanatolica can be postulated (see Table 1) In this paper two species of the genus Graecoanatolica were described.One of these species was collected by Karl-Otto Nagel from south-western Turkey (Province Muğla, Gökova Bay near Akyaka) and ascribed to the genus by the features of shell and female sex tract.The second species has been collected by the junior author during his survey at the Turkish Black Sea coast (Sarikum Lake, Sinop Province).Descriptions of these species are given in this paper.

Material and Methods
The snails were collected by hand and fixed in 60% ethanol.The dissections and measurements of the genital organs and the shells were carried out using a stereo microscope (ZEISS).Measurements of shell height (H), shell diameter (D) and aperture height (h) are given in millimeters.The photographs were taken with a digital camera system (Leica R8).
Holotypes and paratypes of new species are deposited in Senckenberg Museum in Frankfurt (SMF) and Zoological Museum of Hamburg (ZMH).
Animal: Mantle black, snout white, tentacles thick and long.Head dark brown, whitish around the eyes.Eye spots are visible.
Male copulatory organ: Penis simple, without any outgrowth, triangular in shape with a broad basis, in some specimens bent in the middle part (possibly due to the fixation).The distal part of the penis is black pigmented, at the tip acute.Differentiating features: Due to the large dimensions of the shell the new species from Sarikum Lake resembles Graecoanatolica nageli n. sp.From the latter species Graecoanatolica yildirimi n. sp.can be easily distinguished by having an unpigmented penis and a smaller height of shell, and consequently a higher D/H and h/H-h ratios (see: Table 1).

Remark:
We found some specimens with a higher shell and one additional whorl (see remark under G. nageli n. sp. for further discussion).
Habitat: Sarlkum Lake is a shallow brackish coastal lake (184 ha) which discharges through a channel (300 m long) into the sea at period of high water level (Akbulut et al. 2002).Associated species: Theodoxus fluviatilis.