Scandentia is an order of small mammals. Members of this order are called scandentians, or treeshrews. They are primarily found in Southeast Asia, with the Madras treeshrew instead in mainland India. They range in size from the Bornean smooth-tailed treeshrew, at 11 cm (4 in) plus a 9 cm (4 in) tail, to the striped treeshrew, at 23 cm (9 in) plus a 13 cm (5 in) tail. They generally live in forests, and primarily eat insects and fruit. No population estimates have been made for any scandentian species, though the Nicobar treeshrew is categorized as endangered.
The twenty-three extant species of Scandentia are grouped into two families: Tupaiidae, which contains twenty-two species within three genera, and Ptilocercidae, which contains a single species, the pen-tailed treeshrew. Only a few extinct scandentian species have been discovered, though due to ongoing research and discoveries the exact number and categorization is not fixed.[1]