''Xenosiren'' is an extinct genus of
dugong
The dugong (; ''Dugong dugon'') is a marine mammal. It is one of four living species of the order Sirenia, which also includes three species of manatees. It is the only living representative of the once-diverse family Dugongidae; its closest m ...
which existed in Mexico during the Micoene.
[D. P. Domning. 1989. Fossil Sirenia of the West Atlantic and Caribbean region. III. Xenosiren yucateca, gen. et sp. nov. Journal of Vertebrate Paleontology 9(4):429-437]
References
Miocene sirenians
Fossil taxa described in 1989
Prehistoric placental genera
{{Paleo-sirenian-stub