Callistosiren is an extinct genus of mammal which existed in what is now Puerto Rico during the late Oligocene (Chattian).J. Velez-Juarbe and D. P. Domning. 2015. Fossil Sirenia of the West Atlantic and Caribbean region. XI. Callistosiren boriquensis, gen. et sp. nov. Journal of Vertebrate Paleontology e885034
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