Dugong manatee

Sirenia (0/2) In the Sea Cows, the West Indian genus, one of the freshwater Manatees (Trichecus manatus) lacks the organ in the adult, and has a reduced MOS (Mackay-Sim et al., 1985). With the marine Dugong, a similar diminution would be expected but is not proven. 

Sirenia Manatees and dugongs 2 4 <1% Subtropical Atlantic and Indo-Pacific coasts and rivers... 

Manatees and dugongs - sometimes called sea cows - belong to the order Sirenia. They live in the seas around parts of Africa, Australia, Asia, North America, and in the Caribbean. They are not well known and are protected species, so it is very rare to encounter an item made from their bone. However, they should be mentioned because they are unique in that all their bones are compact and not hollow. This has made their bone more versatile for carving than bone from other species, and it has been used as an ivory simulant. 

Manatees and dugongs are the only sirenians. These docile, slow-moving herbivores lack a dorsal fin or hind limbs but are equipped with front limbs that move at the elbow, as well as with a flattened tail. Their powerful tails propel them through the water, while the front limbs act as paddles for steering. 

Sirenia are exclusively herbivorous and live in shallow water, fresh or brackish, near the mouth of or in major rivers in the intertropical zone. Sirenians are mainly represented by manatees (sea cows), found from Florida to Brazil, and the dugong, which lives in the Indo-Pacific zone and on the east coast of Africa, in the Red Sea and the Persian Gulf... 

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