Trichechus manatus Linnaeus, 1758 (Figures 4, 5)

SHSU 1-027. Left edentulous dentary ramus with intact but abraded symphyseal region, labial alveolar surfaces, and posterior margin of the bone intact (Figure 4). The angular process is missing, as is the lingual portion of the alveolar region. Maximum preserved length is 16.5 cm; depth of the dentary at approximate midpoint of the anteroposterior length is 4.9 cm; depth from the top of the coronoid process to the (broken) base of what would be the angular process is 10.4 cm. From the Joe Liggio collection.

SHSU 1-231. Right anterior edentulous maxilla fragment, with a resorbed anterior alveolar region; two complete sets of molar alveoli and part of a third are preserved (Figure 5). Total preserved length is 8.4 cm. From the Brian Babin collection.

The preserved anatomy of SHSU 1-027 allows confident referral to Trichechus manatus, but the portions of the bone that would allow confident referral to T. m. bakerorum, the symphyseal and angular regions of the dentary, are abraded and absent, respectively.