Three new species of Bathysciola Jeannel, 1910 (Leiodidae, Cholevinae, Leptodirini) from caves in Central Italy, comparing morphological taxonomy with molecular phylogeny

The genus Bathysciola is widely distributed in the northern Mediterranean region, although its range extends east to the Caucasus and Iran. More than 130 species belonging to this genus are actually known in the whole geographic distribution area and 45 species are distributed in continental and insular Italy. The species belonging to the Bathysciola sisernicaCerruti and Patrizi, 1952 species group occur in the Central-Southern Italian Apennines and Pre-Apennines. This group consists of seven species, four of which (B. sisernica, B. delayi Latella and Rampini, 1994, B. rampiniiLatella, 2002, B. sbordoni Rampini and Latella, 1993) were already known to science and three are described herein, Bathysciola fabiolae sp. nov., Bathysciola octaviani sp. nov., and Bathysciola valeriae sp. nov., markedly increasing the knowledge on the distribution of this genus in Central Italy. A morphological analysis was carried out based on diagnostic characters usually used to distinguish different taxa, and including both genitalia and external traits. Based on morphological characters, we reconstructed the phylogeny of this group of species, comparing them with the species belonging to other phyletic lineages, such as B. derosasiJeannel, 1914, B. georgi Cerruti, Patrizi, 1952, B. vignai Sbordoni and Rampini, 1978, and B. sarteanensis sarteanensis (Bargagli, 1870). Results suggested that morphological traits show a clear taxonomic signal but a poor phylogenetic signal. To better understand the relationships within this group of species, we performed a molecular analysis by sequencing three mitochondrial genes, 12S rRNA, 16S rRNA, partially sequenced and the entire gene of COI. Molecular markers were used to infer phylogenetic relationships among the Bathysciola sisernica species group and to reconstruct the historical processes that shaped their current geographic distribution. Results showed that these species became isolated in very ancient times, showing very high genetic differentiation.