This treeshrew is 16.0 to 18.5 cm long with a tail of 16.5 to 19.5 cm. The nominate race has the tail coloured like the back, the ground colour above being reddish-brown while the feet and hind legs are buff or ochraceous. The other two races have the tail coloured differently from the back. The race A. e. pallida has the colour of body above reddish-brown and the feet and hind legs grizzled buffy. Race A. e. wroughtoni has the colour of body above dull grizzled brownish and the feet and hind legs grizzled greyish. Some later workers lump all the three races. Its dental formula is. The dentition is suited for an omnivorous diet. Some authors have suggested this species could be included within the genus Tupaia, although most have kept the genus separate based on anatomical differences.
Distribution
The Madras treeshrew is found on the Indian Subcontinent south of the Ganges River. Three subspecies have been described — A. e. ellioti of the Eastern Ghats, Biligirirangan and the Shevaroy Hills and other hills of Southern India, A. e. pallida from Central India primarily in Madhya Pradesh and Raipur, and A. e. wroughtoni from the Satpura Range and the Dangs near Bombay. They have been reported within the Western Ghats ranges of Wayanad and Mahabaleshwar. The northernmost record is from Garhwa district of Bihar. Little is known about the status of these populations as the distribution is patchy, but S. M. Mohnot considered them as "common" in 1975.
Behaviour and ecology
This species of treeshrew is not particularly arboreal and spends much of its time on the ground or clambering about on rocky terrain in the search of insects and seeds. It is easily separated from the squirrels in the field by the shape and color of the tail and the upward curve in which it is held when walking about. They have a behaviour of climbing up low, slanting trunks and sliding down headfirst. This may be associated with scent marking, as many of the Scandentia have scent glands on their throats. A species of sucking louseDocophthirus acinetus is found only on this species, the genus itself being restricted to hosts in the family Tupaiidae. Endoparasitic microfiliriae have also been described from the species. The Crested Hawk-eagle has been known to prey on this tree shrew.