Manatees and Dugongs

Order Sirenia

Sirenia is a small order of fully-marine mammals that consists of 2 families, 2 genera, and 5 species, one of which is extinct. They are recognizable by their flattened tail and cow-like appearance; indeed, they are often called "sea cows." All animals in this order are ungulates (hoofed mammals) even though they have no legs. The flippers are the leg substitutes, and on the flipper tips can be found small hoofnails.

The 2 orders are:

..Dugongidae (dugongs) 2 - (1 extinct) spp
..Trichechidae (manatees) 3 spp

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