Class Mammalia Linnaeus, 1758 - mammals Subclass Theria Parker & Haswell, 1897 Order Pilosa Flower, 1883 - sloths Suborder Folivora Delsuc, Catzeflis, Stanhope & Douzery, 2001 Family Megalonychidae Gervais, 1855 - West Indian sloths and two-toed tree sloths Genus Choloepus Illiger, 1811 - two-toed tree sloths Choloepus didactylus (C. Linnaeus, 1758) - southern two-toed sloth