; superorder Paenungulata, order Sirenia)
A family of aquatic paenungulates in which the upper lip is deeply cleft and each side is capable of independent movement and is used for cropping vegetation. There are no incisors or canines, but the gums form horny pads. There are up to 20 cheek teeth which are peg-like and fall out when worn, probably without being replaced. The tail is unnotched. Manatees occur in coastal waters and rivers in tropical and subtropical America and W. Africa. There are three species in a single genus, Trichechus.
Subjects: Zoology and Animal Sciences.