Sirenia
Dugongidae
Trichechidae

Sīrēnia (-orum, n.) sunt animalia mammifera herbivora aquae orariae. Adaptationes aquaticas evolverunt: bracchia habent, qui in remulos mutaverunt, crura carent, pingues sunt, et crania quae multum mutata sunt et quorum dentitio permaxime deminuta est. Mamillas subalares habent.

Trichechidae a Dugongidis forma et cranii et caudae variant.

Taxinomia 

 ORDO SIRENIA
 Familia Dugongidae
 Dugon, Dugong dugon
 Hydrodamalis, Hydrodamalis gigas (exstincta)
 Familia Trichechidae: manati
 Manatus Caribbeanus, Trichechus manatus
 Manatus Africanus, Trichechus senegalensis
 Manatus Amazonensis, Trichechus inunguis

Clasifficatio 
Ordo: Sirenia 
Familia Prorastomidae (Cope, 1889) 
Genus: Pezosiren (Domning, 2001) 
Genus: Prorastomus (Owen, 1855) 
Familia Protosirenidae 
Genus: Protosiren (Abel, 1907) 
Familia: Dugongidae 
Subfamilia: Halitheriinae 
Genus: Anisotherium (Kordos, 1979) 
Genus: Eosiren (paraphyletic) (Andrews, 1902) 
Genus: Eotheroides (Trouessart, 1905) 
Genus: Halitherium (paraphyletic) (Fitzinger, 1842) 
Genus: Indosiren (Von Koenigswald, 1952) 
Genus: Miodugong (Deraniyagala, 1969) 
Genus: Paralitherium (Kordos, 1977) 
Genus: Prohalicore (Flot, 1887) 
Genus: Prototherium (paraphyletic) (De Zigno, 1887) 
Genus: Sirenavus (Kretzoi, 1941) 
Subfamilia Hydrodamalinae 
Genus: Dusisiren (paraphyletic) (Domning, 1978) 
Genus: Hydrodamalis (Retzius, 1794) 
Genus: Metaxytherium (paraphyletic) (De Christol, 1844) 
Subfamilia Dugonginae 
Genus: Bharatisiren (Bajpai & Domning, 1997) 
Genus: Caribosiren (Reinhard, 1959) 
Genus: Corystosiren (Domning, 1990) 
Genus: Crenatosiren (Domning, 1991) 
Genus: Dioplotherium (Cope, 1883) 
Genus: Dugong (Lacepede, 1799) 
Genus: Rytiodus (Lartet, 1866) 
Genus: Thalattosiren (Sickenburg, 1928) 
Genus: Xenosiren (Domning, 1989) 
Familia Trichechidae 
Subfamilia Miosireninae 
Genus: Anomotherium (Siegfried, 1965) 
Genus: Miosiren (Dollo, 1889) 
Subfamilia: Trichechinae 
Genus: Potamosiren (Reinhart, 1951) 
Genus: Ribodon (Ameghino, 1883) 
Genus: Trichechus (Linnaeus, 1758)

Nexus externi 

Mammalia herbivora

Ordines animalium