Slender loris

The slender lorises (Loris) are two species of loris endemic to India and Sri Lanka that comprise the genusLoris. They are small, gracilestrepsirrhines that weigh between 85 and 340 grams (3.0 and 12.0 oz), with the gray slender loris (L. lydekkerianus) being larger than the insular red slender loris (L. tardigradus). Slender lorises are arboreal, nocturnalprimates that forage solitarily at night and congregate into gregarious groups to sleep during the day. Mothers will leave their infants alone during the night, a behaviour known as "parking", while they forage. Slender lorises maintain predominantly carnivorous diets consisting of invertebrates such as spiders, orthopterans, snails, and ants, as well as vertebrates such as lizards, frogs, and small birds. Between the two slender loris species are seven recognised subspecies, each of which has unique morphological traits such as varying pelage patterns and body proportions. The slender lorises have undergone significant taxonomic revision since they were first described in the 18th century.

The head of a slender loris is distinguished by the presence of large, tapetum-covered eyes that lie close together, exhibiting the lowest interocular distance of all primates. The dentition possesses the typical strepsirrhine toothcomb, which a slender loris can use for grooming itself and others. Accomplishing a similarly hygienic function is a toilet claw of the second pedal digit, which can be used to clean almost any part of the body via a slender loris' remarkable flexibility. Slender lorises have small, pincer-like hands and feet with reduced second digits that allow an individual to powerfully grip a branch for hours at a time while being assisted by specialised blood vessels in the limbs known as retia mirabilia. The spine is characterised by an elongated shape that sways from side-to-side as a slender loris travels across its preferred substrates of twigs, branches, and vines. Pelage patterns are unified by the presence of a thin, vertical white stripe between the eyes, as well as dark circumocular patches.

The gray slender loris is classified as a near threatened species by the International Union for Conservation of Nature, while the red slender loris is classified as endangered. Both species are listed under Appendix II by CITES. Slender lorises are threatened by poaching for the acquisition of body parts for use in traditional medicine, as well as habitat loss.