Dugongidae Gray, 1821
Halianassa collinii
Metaxytherium aquitaniae
Metaxytherium arctodites
Metaxytherium crataegense
Metaxytherium crataegensis
Metaxytherium cuvieri Garden
Metaxytherium floridanum
Metaxytherium krahuletzi
Metaxytherium lovisati
Metaxytherium medium
Metaxytherium riveroi
Metaxytherium serresii
Metaxytherium subapenninum
Thalattosiren petersi