|Pygmy Three-toed Sloth|
|Common Name||Monk Sloth and Dwarf Sloth|
|Range||Isla Escudo de Veraguas, a small island off the coast of Panama.|
The Pygmy three-toed sloth (Bradypus pygmaeus), also known as a monk sloth or dwarf sloth, is a new species of three-toed sloth endemic to Isla Escudo de Veraguas, a small island off the coast of Panama, which separated from the mainland nearly 8900 years ago. Only described as a separate species in 2001, they are thought to have originated from isolation of individuals of the mainland population of brown-throated three-toed sloths. The population became a distinct species through insular dwarfism on the island.
Studies suggest an inverse, linear relationship between mean body sizes and age of the island for island populations of sloths in this region.
All three-toed sloths are arboreal mammals that feed on leaves; the pygmy sloth is unique in that it is found exclusively in the red mangroves, and feeds on coarse leaves. Red mangrove leaves are a relatively poor source of nutrients, in comparison with the tender leaves of the Cecropia tree eaten by brown-throated sloths on the mainland.
The smaller size of pygmy sloths reduces their energy requirements for survival and reproduction, making them an apparent example of insular dwarfism. No predators of pygmy three-toed sloths have been documented.