Myotis alcathoe

The Alcathoe bat (Myotis alcathoe) is a European bat in the genus Myotis. Known only from Greece and Hungary when it was first described in 2001, its known distribution has since expanded to Spain, England, Sweden, and Azerbaijan, among other countries. It is similar to the whiskered bat (Myotis mystacinus) and other species and is difficult to distinguish from them. However, its brown fur is distinctive and it is clearly different in characters of its karyotype and DNA sequences. Although some genetic data suggest that it is related to Geoffroy's bat (Myotis emarginatus), other analyses do not support a close relationship between M. alcathoe and any other species. With a forearm length of 30.8 to 34.6 mm (1.21 to 1.36 in) and body mass of 3.5 to 5.5 g (0.12 to 0.19 oz), Myotis alcathoe is a small bat. The fur is usually reddish-brown on the upperparts and brown below, but more grayish in juveniles. The tragus (a projection on the inner side of the ear) is short, as is the ear itself, and the inner side of the ear is pale at the base. The wings are brown and the baculum (penis bone) is short and broad. M. alcathoe has a very high-pitched echolocation call, with a frequency that falls from 120 kHz at the beginning of the call to about 43 kHz at the end. Usually found in old-growth deciduous forest near water, Myotis alcathoe forages high in the canopy and above water and mostly eats flies. The animal roosts in cavities high in trees. Although there are some winter records from caves, it may also spend the winter in tree cavities. Several parasites have been recorded on M. alcathoe. The IUCN Red List assesses Myotis alcathoe as 'data deficient', but it is considered threatened in several areas because of its rarity and vulnerability to habitat loss. The whiskered bat (Myotis mystacinus) and similar species in Eurasia (collectively known as 'whiskered bats') are difficult to distinguish from each other; for example, the distantly related Brandt's bat (Myotis brandtii) was not recognized as distinct from M. mystacinus until the 1970s. Small, unusual M. mystacinus-like bats were first recorded in Greece in the 1970s, but it was not until the advent of genetic studies that these bats could be confirmed as representing a distinct species, named Myotis alcathoe. In 2001, the species was described by German zoologists Otto von Helversen and Klaus-Gerhard Heller on the basis of specimens from Greece and Hungary. Although it also differs from other whiskered bats by morphological characters, Myotis alcathoe is most clearly distinct in its genetics, including DNA sequences and the location of the nucleolus organizer regions. Two studies used microsatellite markers on European whiskered bats: the first one used western European samples and recovered three well-defined species clusters for M. alcathoe, M. brandtii and M. mystacinus; the other one, conducted in Poland, suggesting a high level of hybridization with other whiskered bats that would further complicate attempts to identify M. alcathoe morphologically. Von Helversen and Heller argued that none of the old names now considered synonyms of M. mystacinus could apply to M. alcathoe, because these names all have their type localities in western or central Europe. However, the more recent discovery of M. alcathoe further to the west renders it possible that an older name may be discovered. In addition, Russian researcher Suren Gazaryan has suggested that the name caucasicus Tsytsulina, 2000 (originally proposed for a subspecies of M. mystacinus from the Caucasus) may prove to be applicable to M. alcathoe; in that case, the species would be renamed Myotis caucasicus. The species may have remained undetected in Germany for so long because bat researchers did not sample its preferred habitats and would dismiss unusual-looking whiskered bats as being abnormal M. mystacinus or M. brandtii. On the basis of mitochondrial DNA sequence analysis, Myotis alcathoe first appeared close to Geoffroy's bat (Myotis emarginatus) of southern Europe, North Africa, and southwestern Asia. However, a study of the mitochondrial cytochrome b gene incorporating many Myotis species did not support this relationship, and could not place M. alcathoe securely at a specific position among Eurasian Myotis. Two groups with slightly divergent mitochondrial DNA sequences (separated by 1.3 to 1.4% sequence divergence) are distinguishable within the species, which probably correspond to different glacial refugia where M. alcathoe populations survived the last glacial period. One, known as the 'Hungarian' group, has been recorded from Spain, France, Austria, Hungary, and Slovakia, and probably corresponds to a refugium in Iberia; the other, the 'Greek' group, is known only from Greece and Slovakia. The specific name, alcathoe, refers to Alcathoe, a figure from Greek mythology who was turned into a bat when she refused the advances of the god Dionysus. She was associated with gorges and small streams, the preferred habitat of Myotis alcathoe in Greece. In their original description, von Helversen and colleagues described her as a nymph, and the common name 'nymph bat' has therefore been used for this species. However, none of the classical sources speak of Alcathoe as a nymph; instead, she was a princess, the daughter of King Minyas of Orchomenos. Therefore, Petr Benda recommended in 2008 that the common name 'Alcathoe bat' or 'Alcathoe myotis' be used instead. Other common names include 'Alcathoe's bat' and 'Alcathoe whiskered bat'. Myotis alcathoe is the smallest European Myotis species. The fur is brownish on the upperparts, with a reddish tone in old specimens, and a slightly paler gray-brown below. Younger animals may be completely gray-brown. The brown fur distinguishes adult M. alcathoe from other whiskered bats, but juveniles cannot be unambiguously identified on the basis of morphology. M. alcathoe is similar to Daubenton's bat (Myotis daubentonii) and M. emarginatus in color. On the upper side of the body, the hairs are 6 to 8 mm long and have dark bases and brown tips. The hairs on the lower side of the body are only slightly paler at the tip than at the base.