Arielulus circumdatus (Temminck, 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 : 231-232

Arielulus circumdatus

Black Gilded Pipistrelle

Vespertilio circumdatus Temminck, 1840: 214 ; Tapos, Java

Previous records from Myanmar

Kachin State: Pyepat ( Hill, 1972).

Descriptive characters

No specimens from Myanmar were seen. The following description is based on extralimital specimens from India, Cam- bodia and Java. Forearm length is 41.8–43.6 mm ( Bates and Harrison, 1997). The hair bases on the dorsal surface are black; their tips are a rich, glossy chestnut-brown, which gives an almost orange sheen to the head and back. The ventral surface is a uni- form brown, paler than the back; the hair roots are slightly darker than the tips. The membranes are a uniform dark brown. The fifth metacarpal is about equal in length to the third and fourth. The penis is not greatly enlarged. The baculum is very small, Y- shaped, with paired basal lobes and a short shaft ( Fig. 1H ). In the skull, the rostrum is very broad and relatively short. The zygo- mata are robust. The basioccipital pits are well developed. The rostrum is sharply angulated inwards posterior to the lachrymal projections. The second upper incisor (I3) is small, scarcely projecting beyond the cingulum of the first (I2). The first upper premo- lar (P2) is minute, one eighth to one quarter the area and height of the first incisor (I2). The first lower premolar (P2) is situated in the toothrow and is one quarter to one third of the crown area of the second (P4).

Similar species

Arielulus circumdatus is distinguished from all other pipistrelle type species in Myanmar by its size and pelage colour.

Ecology

In March 1939, a single specimen was shot at twilight on the forest trail leading to the Pyepat rest house, which was situated at an altitude of 1,940 m (6,300 feet) on a small, steep sided, ridge in a forest clear- ing. The forest was temperate and included

oaks, laurels and rhodendrons. The ground was damp, and the banks along the trail were covered with dense masses of ferns, mosses and begonias with an occasional Primula, several species of orchid, gentians and many other plants. According to An- thony (1941), the ridge is a long, narrow intrusion of temperate flora and fauna into the tropical ecology found in the two river valleys.

Figures

FIG. 1. Bacula of nine species of Pipistrellus, Arielulus and Ia. Lateral (above) and dorsal (below) views of: A — P. ceylonicus. HZM.3.31458, Sri Lanka; B — P. coromandra. MN2 (HZM.9.35441), Myanmar; C — P. tenuis. MV14 (HZM.11.35444), Myanmar; D — P. pulveratus. BD14, Myanmar; E — P. lophurus. After Hill and Harrison (1987); F — P. cadornae. HZM.3.32165, Vietnam; G — P. affinis. H22 (HZM.2.35125), Myanmar; H — A. circumdatus. After Hill and Harrison (1987); I — I. io. HZM.4.32150, Vietnam. Scale = 2 mm