Taxonomic revision of Myotis emarginatus: detailed morphometric analysis and final evaluation of the evidence (Chiroptera: Vespertilionidae)

Abstract

The Geoffroy’s bat, Myotis emarginatus, is the only species distributed in the Palaearctic belonging to the African clade of the genus Myotis. It occurs extensively across several ecologic zones of Europe, north-western Africa, and western and central Asia, and hence it was considered to be a polytypic species. Only one subspecies was reported from Europe and North Africa, up to four subspecies were recognised in Asia. However, the validity of particular taxa as well as the systematic positions of different populations remained ambiguous. Here we present a revision of the intraspecific phylogenetic structure of M. emarginatus based on combination of the available results of a molecular genetic analysis with the results of a thorough morphologic examination of an extensive specimen set from almost the whole range of its distribution. The previously described geographic variability in the mitochondrial markers demonstrated grouping of haplotypes of M. emarginatus into three main lineages that occur in (1) the Mediterranean Basin (including central Europe, the Maghreb and Levant), (2) Oman and south-eastern Iran, and (3) northern Iran and West Turkestan. The morphologic comparison uncovered the existence of four main, geographically exclusive morphotypes in M. emarginatus, concerning the body, skull and tooth sizes, and skull and tooth shapes: (1) rather small bats with short rostrum and high braincase, occurring in Europe and north-western Africa; (2) rather medium-sized bats with long rostrum and short braincase from the Levant including Cyprus; (3) large bats with wide and long rostrum from the south-eastern parts of the Middle East, including Oman, south-eastern Iran and eastern Afghanistan, and (4) large bats with narrow and short rostrum, occurring in Crimea, the Caucasus region, and West Turkestan. As a synthesis of the results of both approaches, we suggest to recognise three subspecies within the Myotis emarginatus species rank – M. e. emarginatus (Geoffroy, 1806) distributed in the Mediterranean, central and western Europe, north-western Africa, and in the Levant; M. e. desertorum (Dobson, 1875) in the south-eastern Middle East, including southern Iran, Oman, and Afghanistan; and M. e. turcomanicus (Bobrinskoj, 1925) in the Caucasus region, Crimea, Transcaucasia, and West Turkestan.