Myotis horsfieldi, 1840

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 : 217

Myotis horsfieldi

Horsfield’s Bat

Vespertilio horsfieldii Temminck, 1840: 226 ; Mount Gede, Java

New material from Myanmar

Kayin State: Bayint Nyi Cave, 14.11. 2002, 1 ♂ (H15); Mon State: Indian Single Rock Temple Cave, 19.11.2002, 1 ♂ (H23) and -.5.2003, 1 ♂ (KMM1).

Previous records from Myanmar

Mon State — Kyauk-Ta-Lone ( Bates et al., 2001).

Diagnostic description

A medium-small species of Myotis with a forearm length of 33.8, 34.0 mm based on two specimens from Myanmar ( Table 4) (FA = 36.5–41.5 mm in Bates and Harrison, 1997; 34.3–36.8 mm in Hendrichsen et al., 2001 and 34 –37 mm in Borissenko and Kruskop, 2003). The dorsal pelage is dark- grey brown. The ventral pelage is paler, with buff-brown hair tips and dark roots. The feet are enlarged and exceed half the length of the tibiae. The wings are attached to the outer metatarsals of each foot. The upper canine (C1) is nearly twice the height of the third upper premolar (P4). The second upper premolar (P3) is about half the crown area of the first (P2) and usually lies within

the toothrow. The lower canine (C1) exceeds the third lower premolar in height (P4). The second lower premolar (P3) is about half the crown area of the first (P2).

Similar species

The distinction of M. horsfieldi from M. hasselti is discussed above.

Taxonomic notes

The external, skull and dental measurements of the Myanmar specimens are small when compared to those listed in Hill (1983) for M. h. peshwa ( Thomas, 1915 c) from peninsular India and M. h. deignani Shamel, 1942 from Thailand. They compare more favourably to those of the nominate race from Malaysia and Java.

Ecological notes

In Myanmar, all three specimens were found in or near limestone caves. Initially collected in March, 2001 near Kyauk- Ta-Lone village, it was flying over a small watercourse that runs through an area of agricultural land, disturbed woodland and limestone outcrops ( Bates et al., 2001). Subsequently in May, 2003, it was collect- ed again in the same vicinity at Indian Temple Cave, which is situated some 800 m from the original point of capture. The last individual was collected in the tunnel- like limestone cave of Bayint Nyi, which is an area of disturbed woodland and some agriculture.