Myotis mystacinus

Bates, Paul J. J., Nwe, Tin, Bu, Si Si Hla, Mie, Khin Mie, Swe, Khin Maung, Nyo, Nyo, Khaing, Aye Aye, Aye, Nu Nu, Toke, Yin Yin, Aung, Naing Naing, Thi, Mar Mar & Mackie, Iain, 2005, A review of the genera Myotis, Ia, Pipistrellus, Hypsugo, and Arielulus (Chiroptera: Vespertilionidae) from Myanmar (Burma), including three species new to the country, Acta Chiropterologica 7 (2), pp. 205-236 : 209-210

Myotis mystacinus

Whiskered Bat

Vespertilio mystacinus Kuhl, 1819: 202 ; Germany

New material from Myanmar

Shan State: Hta Ein Cave, 15.8.2003, 1 ♂ (IL2). There are no previous authenti- cated records. Tun Yin (1993) listed M. my- stacinus muricola for Myanmar (with no precise locality) but based on his descrip- tion of the pelage, it is here included in M. muricola .

Descriptive characters

A small Myotis with a forearm length of 35.1 mm, based on a single specimen from Myanmar ( Table 4; FA = 34.5–36.8 mm for extralimital specimens in Bates and Har- rison, 1997). The feet are not enlarged, about half the length of the tibiae. The hairs of the dorsal pelage have grey buff- brown tips and darker brown roots. On the ventral surface, the hair tips are white with black bases. The ears are narrow, with a tall narrow tragus. The skull ( Table 5) is

moderately elevated and bulbous. The upper canine (C 1) exceeds the third premolar (P4) in height. The first upper premolar (P2) is small, with the second (P 3) about two- thirds the crown area of P 2, both lie in the toothrow. The second lower premolar (P 3) is between half and two-thirds the crown area and height of the first (P 2).

Similar species

The dorsal and ventral pelage, ears, interfemoral and wing membranes of M. mystacinus are paler than those of M. muricola . The feet of M. mystacinus exceed those of M. muricola in size, both in absolute terms and relative to the length of the respective tibiae. In extralimital material, the skull of M. mystacinus averages larger than that of M. muricola ( Bates and Harrison, 1997) and the braincase and rostrum are more elevated when viewed laterally. Toothrow length exceeds that of M. murico- la but the morphology of the teeth are es- sentially similar in both species.

Taxonomic notes

There has been much taxonomic confu- sion between M. mystacinus and M. murico- la and all previous records of M. mystacinus from South-East Asia, for example Van Peenan et al. (1969), Sokolov et al. (1986) and Lekagul and McNeely (1988), were omitted by Corbet and Hill (1992) and Koopman (1993). They are thought to be referable to M. muricola . A detailed discus- sion of the differences between the two taxa was included in Hill (1983) and further in- formation from Vietnam is included in Bates et al. (1999). The recent specimen from Myanmar is therefore the first authenticated record for South-East Asia.

Ecological notes

The specimen from Shan State was collected in a mist net set at the entrance of a limestone cave (Hta Ein Cave). The cave, one of two on the eastern slope of the valley

of the Hsindaung stream, is situated at the base of the range of mountains forming the eastern edge of the Yawnghwe Valley. The caves face westwards towards Inlay Lake and are about 100 m above the lake’s sur- face at an altitude of 1,400 m. The area was once covered in moist broadleaf forest. This has been extensively cleared for agriculture and most of the hills and valleys are now heavily degraded. The climate is relatively cool in comparison to the nearby Ayeyar- wady River valley, with warm wet summers and cool dry winters.