List of sirenian taxa and categorization of corresponding ecomorphological features used in this study.

aSmall, length less than half the length of the premaxillary symphysis; medium, length about half the length of the premaxillary symphysis; large, length greater than half the length of the premaxillary symphysis.bEstimate based on condylobasal length of skull of 41.5 cm.cBased on Nanosiren garciae with which it shares similar dimensions of the mandible.