The world’s gliding mammals are an extraordinary group of animals that have the ability to glide from tree to tree with seemingly effortless grace. There are more than 60 species of gliding mammals including the flying squirrels from Europe and North America, the scaly-tailed flying squirrels from central Africa and the gliding possums of Australia and New Guinea.
Description: A medium-sized species with deep brown fur on its upper parts, each hair being grey at the base; and abundantly interspersed with longer hairs, which are bright brown or reddish-yellow colour at the tip. The hairs on its underparts are a yellow-white and not grey at the base.
The tail is a uniform bright rust colour beneath. The margin of its patagium is of a reddish-yellow colour, as are also the sides of its face below its eyes.
Distribution: Occurs on the Malay Peninsula, Singapore, Java and Sumatra, Penang Island and western Borneo. Its habitat includes partially cut primary forest and secondary forest. It is common near more disturbed replanted areas in Malaysia where it replaces the Smoky Flying Squirrel, which prefers primary and partially cut forest.
On the Malay Peninsula it is widespread and relatively common in forest plantations at all elevations. In Borneo it is known from scattered localities throughout the west in forests, plantations and gardens with tall trees up to 1650 metres on Gunung Kinabalu in Sabah, south to Brunei, Sarawak and Batu Jurong in West Kalimantan.
There is also one record from Sandakan, but none from East, South or Central Kalimantan. Most records are from lowlands and hills. Also recorded from the Kelabit uplands in Sarawak and up to 1800 metres on Gunung Kinabalu.
Reproduction: Limited information available suggests that it produces one to four young with an average of two.
Diet: Includes seeds and fruit. This species is considered a pest in some villages as it feeds on the fruits of plantations including coconut plantations.
Ecology: Little is known. Although it generally sleeps in holes, one collector reported shooting this species from a leafy nest in the crown of a 6 metre tree in Borneo.
Status: Least Concern.
Iomys horsfieldi horsfieldi — Java and Sumatra.
Iomys horsfieldi davisoni — Malay Peninsula, Singapore (extinct?) and Tioman Island.
Iomys horsfieldi penangensis — Penang Island.
Iomys horsfieldi thomsoni — Borneo.