Synurella odessana sp. n. (Crustacea, Amphipoda, Crangonyctidae), first report of a subterranean amphipod from the catacombs of Odessa and its zoogeographic importance

Abstract

A new species from the catacombs of Odessa (South Ukraine), Synurella odessana sp. n. is described and its taxonomic affinity with congeners are discussed. This is the first record of the subterranean amphipod crustacean of the genus Synurella from an artificial biotope. The new species has numerous plesiomorphic features states allowing a more detailed evaluation of the taxonomy of the genus Synurella. The most remarkable feature of this new species is the presence of a "synurellid type" gnathopod 1 and a "crangonyctid type" gnathopod 2. Herein, we propose three groups in the genus Synurella distributed within the Volga-Black Sea basin: ambulans-group (epigean inhabitants of coastal lowlands, stygophiles), dershavini-group (hypogean or spring inhabitants of karstic regions, preadapted stygobionts), wachuschtii-group (minute inhabitants of interstitial waters, stygobionts). The dershavini-group occupies isolated taxonomic position among the synurellids. We suggest that the modern distribution of dershavini-group reflects the formation of ancient river basins in the region.