Barbastella caspica (Chiroptera, Vespertilionidae) in China: first record and complete mitochondrial genome

The Caspian barbastelle, <i>Barbastellacaspica</i>, has spread widely in the Caspian region, Iran, and Central Asia; however, there is no evidence of its occurrence in China so far. During a field investigation, we collected a single specimen of <i>B.caspica</i> in China's Xinjiang Uyghur Autonomous Region. At the same time, we obtained the free-flight echolocation calls of the bat. It omitted signals with start frequency of 33.15 ± 1.43 kHz, end frequency of 29.82 ± 0.40 kHz, frequency of most energy 31.48 ± 0.40 kHz, duration of 2.43 ± 0.24 ms, and a pulse interval of 246.57 ± 9.48 ms, which are probably type-I sounds emitted through the mouth. We also sequenced its entire mitochondrial genome to elucidate the genomic structure and its evolutionary relationships with closely related <i>Barbastella</i>. The mitochondrial genome of <i>B.caspica</i> spans 16,933 bp, comprising 13 protein-encoding genes, 22 transfer RNA genes, two ribosomal RNA genes, and a displacement loop/control region. Consistent with previous bat mitogenome reports, the majority of mitochondrial genes are encoded on the heavy chain. A phylogenetic analysis based on 13 protein-coding genes revealed that <i>Rhogeessa</i>, <i>Plecotus</i>, and <i>B.caspica</i> formed a clade within Vespertilionidae. <i>Barbastellacaspica</i> was found to be a sister species to <i>B.beijingensis</i> and <i>B.leucomelas</i> in phylogenetic trees using the cytochrome <i>b</i> and <i>ND1</i> gene sequences. This is the first report of the mitogenome of a member of the genus <i>Barbastella</i>, as well as the first record of the distribution of <i>B.caspica</i> in China and first documentation of its echolocation calls.