419.

Siberian Whiskered Myots

Myotis sibiricus

French: Murin de Sibérie / German: Sibirien-Mausohr / Spanish: Ratonero de Siberia

Other common names: Siberian Myotis

Taxonomy. Vespertilio mystacinus sibiricus Kastschenko, 1905,

Tomsk, Russia.

Subgenus Pizonyx; brandtii species group. Myotis sibiricus is traditionally considered a subspecies of M. brandi under the name M. b. gracilis, which is now considered a synonym of M. sibiricus . Myotis gracilis has been variously recognized as a distinct species, but M. sibiricus 1s the oldest available name and thus has nomenclatural priority. Myotis sibiricus appears to be sister species to M. brandtii, but they are very tae Both species are very peculiarly embedded in the New World clade of Myotis, although the exact position of M. brandtii and M. sibiricus with respect to the New World Myotis is still not completely clear. Monotypic.

Distribution. E Asia from NE Mongolia to Russian Far East, NE China, Korea (including Jeju I), N Japan (Hokkaido), and Kuril Is.

Descriptive notes. Head-body 38-51 mm,tail 32-45 mm, ear 12-15- 5 mm, hindfoot 8-10 mm, forearm 32-38 mm; weight 4-9- 5 g. The Siberian Whiskered Myotisis relatively small. Fur is shaggy and long. Dorsal pelage is dark brown to yellowish brown (hairs with metallic sheen on tips); venter is paler and grayer than dorsum. Bare parts of ears, muzzle, and membranes are dark brown. Ears are not truncated but are rounded at tips, and anterior margins are turned outward above centers; tragusis straight or slightly turned outward, being under one-half the ear length. Wing attaches to distal part of metatarsus on first toe, and calcar is long, lacking postcalcarial lobe. Uropatagium has straight vein running to ankle from just above base oftail. Anteorbital ridge is distinct, and lacrimal foramen is not exposed; braincase is low; basicochlear fissure 1s long; P? and P, are in tooth rows; and upper molars have protoconules. Chromosomal complement Bos 2n = 44 and FN = 50 (Korea).

Habitat. Generally forested habitats at higher elevations and agricultural areas at lower elevations.

Food and Feeding. Siberian Whiskered Myotis fly low and forage along streams between mountains and agriculturalfields.

Breeding. Births of Siberian Whiskered Myotis probably occur in early July in Korea and Japan, and lactating females have been observed from late July to early August in Hokkaido. Females have one young per pregnancy.

Activity patterns. Siberian Whiskered Myotis emerge in early evening and forage through the night. They use hollowsin trees for roots and will use caves as hibernacula. Calls are steep FM sweep, apparently with peak frequencies of 32-45 kHz.

Movements, Home range and Social organization. Siberian Whiskered Myotis are known to roost alone, with one individual using a hole or crevice in a cave for hibernation. Maternity colonies can have 20-60 females and their young.

Status and Conservation. Not assessed on The [UCN Red List. The Siberian Whiskered Myotis was previously included in Brandt's Myotis ( M. brandtii), which is classified as Least Concern. The Siberian Whiskered Myotis is widespread but rare throughout much of its distribution.

Bibliography. Jo Yeong-Seok et al. (2018), Kawai et al. (2003), Kruskop et al. (2012), Ohdachi et al. (2009), Stadelmann et al. (2007), Yoo & Yoon Myung-Hee (1992).