Sirenídeos

Sirenídeos refers to the order Sirenia, a group of herbivorous aquatic mammals commonly known as sea cows. This order includes extant species such as dugongs and manatees. Sirenians are characterized by their streamlined bodies, paddle-like forelimbs, and a fluked tail. Their hind limbs are vestigial and not visible externally. They are entirely aquatic, spending their lives in shallow coastal waters, estuaries, and rivers. Sirenians are herbivores, feeding primarily on seagrasses and other aquatic vegetation.

The order Sirenia is divided into two extant families: Dugongidae, which contains only the dugong (Dugong dugon), and Trichechidae, which includes the three species of manatees. Historically, the Steller's sea cow (Hydrodamalis gigas) was also part of this order but became extinct in the 18th century due to overhunting.

Sirenians are found in tropical and subtropical regions worldwide. Manatees inhabit the Atlantic coast of North America, the Caribbean, and the Amazon basin, while dugongs are found in the Indo-Pacific region. These animals are generally slow-moving and have a placid nature. They are air-breathing mammals and must surface regularly to inhale. Their slow metabolism and dependence on specific aquatic vegetation make them vulnerable to habitat destruction, pollution, and collisions with boats. Conservation efforts are in place to protect several sirenian species, many of which are listed as vulnerable or endangered.