The mammalian order Pilosa, which includes the sloths and anteaters, includes various species from the Caribbean region. Many species of sloths are known from the Greater Antilles, all of which became extinct over the last millennia, but some sloths and anteaters survive on islands closer to the mainland. For the purposes of this article, the "Caribbean" includes all islands in the Caribbean Sea (except for small islets close to the mainland) and the Bahamas, Turks and Caicos Islands, and Barbados, which are not in the Caribbean Sea but biogeographically belong to the same Caribbean bioregion.

Overview

Extinct sloths are known from the three Greater Antilles of Cuba, Hispaniola, and Puerto Rico and several smaller Antillean islands, but they are missing from the fourth of the Greater Antilles, Jamaica. These were formerly believed, on the basis of morphological studies, to be part of the family Megalonychidae, which includes some of the extinct giant ground sloths, such as Megalonyx, and was formerly also thought to include the living two-toed sloths (Choloepus) of the American mainland. Recent molecular evidence from collagen and mitochondrial DNA sequences has shown that this construction of Megalonychidae is polyphyletic; the Caribbean sloths form a basal branch of the sloth evolutionary tree and are not close to either Choloepus or Megalonyx. The extinct Caribbean sloths appear to represent a single radiation which has been designated as the family Megalocnidae. All Greater Antillean sloths are now extinct; their extinction by ~4400 BP (uncalibrated radiocarbon date) apparently postdated the extinction of the mainland ground sloths by about six thousand years, and coincided (to within a thousand years) with the arrival of humans on the islands. These sloths apparently had a wide range of locomotor habits corresponding to varying degrees of arboreality, but were generally more terrestrial than extant tree sloths. They had been present on the Antilles since the early Oligocene, 32 million years ago. The subdivision of Antillean sloths into several subfamilies has been interpreted as implying at least a diphyletic origin for them, requiring two or more separate colonization events; however, the molecular results indicate the group is monophyletic. In addition to the Greater Antillean sloths, some other pilosans are still extant on islands close to the Central and South American mainland. This includes several anteaters and a member of the other extant sloth family, that of the three-toed sloths, restricted to a small island in Panama. The record of a tamandua from Cozumel, off Mexico, was probably in error. The genera of Caribbean pilosans are classified as follows (with extinct taxa designated by the dagger, †):

Cuba

Cuba is the largest of the Greater Antilles. A diverse assortment of sloths is known.

Hispaniola

Hispaniola, the second largest of the Greater Antilles, is divided into Haiti and the Dominican Republic. It had a diverse sloth fauna.

Tortuga

Tortuga is an island off northern Haiti.

Gonâve

Gonâve is an island off southwestern Haiti.

Puerto Rico

Only one sloth is known from the Quaternary of Puerto Rico, the easternmost of the Greater Antilles; another species is known from much older, Oligocene, sediments.

Grenada

Grenada is the southernmost island of the main Lesser Antillean island arc.

Trinidad

Trinidad is a large island off northeastern Venezuela. It hosts two species of anteaters that are also found on mainland South America.

Curaçao

Curaçao is a Dutch island off northwestern Venezuela.

Escudo de Veraguas

Escudo de Veraguas is an island off northern Panama. Despite its small size, it supports two mammal species found nowhere else: the bat Dermanura watsoni incomitata and the only extant Caribbean sloth.

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