Horsfield's Bat (Myotis horsfieldii)
HB:51; T:35; FA: 34.6-36.2; HF: 8.5-8.8; W: 7.5-8.5g
There are two kinds of fur; the shorter coat has , individual hairs with 3 bands, dark brown or black at the base, followed by a pale buff band, then a narrow dark brown band, with flaxen tips; the longer courser coat extending beyond the short hairs is black with flaxen tips. The intermingling of the 2 types of hair gives the back a grizzled grey appearance. The underparts are lighter brown, with individual hairs having dark brown bases with pronounced buffy tips. The wings and interfemoral membrane are dark grey; the tip of the tail projects slightly beyond the membrane. The second lower premolar is half the height of the first, but within the toothrow; the second upper premolar is within the toothrow, but so small that the first and third upper premolars are nearly in contrast (Medway 1969)
This wide ranging species has been recorded from South Asia,
Southern China and much of Southeast Asia. In South Asia, this species is
presently known from India (Andaman and Nicobar Islands [Great Nicobar, Little
Nicobar and Car Nicobar], Goa, Karnataka, Kerala, Madhya Pradesh, Maharashtra
and Tamil Nadu) (Aul and Vijaykumar 2003, Molur et al. 2002, Vanitharani 2006).
It has been recorded from sea level to around 800 m asl (Molur et al. 2002). In
China, it is found in Guangdong, Hainan and Hong Kong (Smith and Xie 2008). In
mainland Southeast Asia, it ranges from Myanmar in the west, through
Lao PDR, Vietnam, Cambodia, Peninsular Malaysia and possibly Singapore. Within
insular Southeast Asia, it has been recorded from Indonesia (the islands of
Java, Lombok and Sulawesi), Borneo (Brunei, Indonesia and Malaysia) and the
Philippines, where it has been recorded from sea level to 800 m asl (Heaney et
al. 1998) although there is a record from 1,450 m asl on mount Isarog Camarines
Sur Province, in the South Eastern portion of Luzon Island. There are records
from the Philippine islands of Bohol, Catanduanes, Luzon (Camarines Sur,
Cagayan, Laguna, Pampanga, Quezon, and Rizal provinces), Mindanao (Lanao del
Norte Province, Misamis Occidental), Negros, and Palawan (Heaney et al. 1998)
and Polillo (Gonzales pers. comm. 2006).
Brunei Darussalam; Cambodia; China; Hong Kong; India (Andaman Is.); Indonesia (Bali, Jawa, Kalimantan, Sulawesi); Lao People's Democratic Republic; Malaysia; Myanmar; Philippines; Thailand; Vietnam
This is a moderately common species over much of its range.
The abundance, population size and trends for this species in South Asia are not
known (Molur et al. 2002).
Population Trend: Stable
Habitat and Ecology:
In South Asia, this species is found in prime forests and tea
estates near to water source. It roosts in tunnels, caves, bridges, palm fronds,
crevices in old buildings, cracks and hollows between wooden beams (Aul and
Vijaykumar 2003) either singly or in small groups of a few individuals (Bates
and Harrison 1997). In Myanmar the species has been recorded in lowland forests
and agricultural areas adjacent to limestone karst, it has also been collected
in a limestone cave in disturbed forest (Bates pers. comm. 2006). In Viet Nam
(Borissenko and Kruskop 2003), Thailand (S. Bumrungsri pers. comm.) and
the Philippines, it has been recorded near to streams in lowland forest,
disturbed forest and agricultural areas. In the Philippines, it sometimes roosts
in caves and in tunnels and has been reported roosting beneath a large rock over
a stream (Taylor, 1934).
There appear to be no major threats to this species as a
whole. In South Asia, the habitat of this species is being deforested for
timber, firewood and conversion for agricultural use. It is also threatened
through disturbance of roosting sites (Molur et al. 2002).
The species has been recorded from many protected areas. Within India, the species has been recorded from the Silent Valley National Park in Kerala, Agasthiyamalai Biosphere Reserve in Tamil Nadu (Vanitharani 2006) and Kanha National Park in Madhya Pradesh. Further studies on distribution, abundance, breeding biology, general ecology and population monitoring are recommended (Molur et al. 2002).