The role of Anatolia in the origin of the Caucasus biodiversity hotspot illustrated by land snails in the genus Oxychilus.

Several taxa that are distributed in the Caucasus and/or the adjacent Pontic Mountains also have representatives in the East Mediterranean region. These disjunctions could have been caused by long-distance dispersal or be the result of extinctions in Central Anatolia caused by the aridification of the Anatolian Plateau during the Pliocene. We studied the Longiphallus-Hiramia group of Oxychilus as an example showing such distribution patterns. Phylogenetic analyses of the Oxychilus species previously classified in Longiphallus, Hiramia and related subgenera resulted in a new delimitation of these taxa and the recognition of Anatoloxychilus Neiber, Walther & Hausdorf n. subgen. as an additional clade. Based on phylogenetic and population genetic analyses, O. reticulatus from Mingrelia is revalidated and the populations from the Pontic Mountains previously identified with O. mingrelicus koutaisanus are recognised as a distinct species. Three species pairs of the Longiphallus-Hiramia group with deep splits predating the aridification of the Anatolian Plateau during the Pliocene show disjunctions between the Caucasus/Pontic region and the Mediterranean. The majority of taxa with such a distribution pattern probably had more continuous distributions before the aridification started. The relationships between the Hiramia species from the Caucasus, the Pontic Mountains and the East Mediterranean highlight the importance of the Anatolian land as a source area for the colonisation of the Caucasus region. The dating of the divergences of the Caucasian Hiramia species in the middle to late Miocene indicated that they colonised the Caucasus when it was still an island in the Paratethys Sea and that their divergence was triggered by the orogenesis of the Greater Caucasus. A common pattern within the Caucasus region, also found in Hiramia, is the separation of taxa in the north-western Greater Caucasus from taxa inhabiting the southern slopes of the central Greater Caucasus.

A revision of the Pontocaspian gastropods of the subfamily Caspiinae (Caenogastropoda: Hydrobiidae).

The Caspiinae comprise small gastropod species inhabiting low-salinity environments of the Pontocaspian region, specifically the Caspian Sea and the limans, estuaries and lower river reaches of the northern Black Sea Basin. There is considerable discrepancy in the literature as to which taxa are attributed to this hydrobiid subfamily, which of them are valid and what rank they have. Moreover, the generic classification is not agreed upon. Here, we aim at elucidating systematic relationships and species identities by a thorough taxonomic and systematic revision of the Caspiinae, including a detailed morphological study along with information on biogeography, ecology, conservation and fossil record. We use historical and recent collections from all around the Pontocaspian region acquired over the past 170 years, including several type series that were only recently discovered as well as selected Pleistocene and Holocene materials. Several of the species are illustrated properly here for the first time, using both macrophotographs and scanning electron microscopy images to facilitate evaluation of morphological details. The genus Andrusovia, which has been classified in a number of different families and even gastropod subclasses before, is here attributed to the Caspiinae. By designating a lectotype for the type species, A. dybowskii, we finally fix the identity of this previously ambiguous species and genus. Our revision yields four genera and eleven accepted species of Caspiinae for the modern Pontocaspian fauna: Andrusovia (1), Caspia (1), Clathrocaspia (7) and Ulskia (2). In addition, two species of uncertain status (1 nomen dubium, 1 taxon inquirendum) are discussed, and two species introduced as Caspiinae are here found not to belong in that group. Andrusovia antecessor sp. nov. and Andrusovia cyrensis sp. nov. are introduced as new (sub)fossil species from the Caspian Sea.

Redescription of Vertigo (Vertigo) nitidula (Mousson, 1876) (Gastropoda: Vertiginidae) from the Caucasus region.

A revision of material of a minute land snail species from the Caucasus region usually named Vertigo (Vertigo) sieversi (Boettger, 1879) (Pilsbry 1919; Schileyko 1984; Sysoev & Schileyko 2005; Egorov 2008; Sysoev & Schileyko 2009), including types of all described varieties revealed that adjustments of the delimitation and the nomenclature of this insufficiently known taxon are necessary. We reinstate the oldest available name, Vertigo (Vertigo) nitidula (Mousson, 1876), for this species, redescribe it, and discuss its distinction from Vertigo (Vertigo) substriata (Jeffreys, 1833) as well as its geographical range.