Wall, W.P.; Heinbaugh, K.L.
taxonomy · morphology · ecology · biogeography · range
Comparative anatomical analysis of orbital position, axial skeleton and limb leverage in M. planifrons and other amynodontids, explicitly testing rather than assuming semi-aquatic locomotion. This National Park Service technical-report chapter has no assigned DOI.
Comparative anatomy of Metamynodon planifrons—high orbits, reduced thoracic spines and limb-lever differences—together with channel-sandstone association supports a semi-aquatic locomotor inference, not direct observation or a family-wide amynodont ecology.
claim:taxon:metamynodonMetamynodon is treated as an amynodontid genus, with the detailed locomotor profile restricted to M. planifrons specimens used in the comparative study.
claim:taxon:metamynodon:taxonomyThe atlas’s 40.4–23 Ma occurrence envelope remains provisional; the cited anatomical study independently anchors Orellan M. planifrons material but does not validate exact global endpoints.
claim:taxon:metamynodon:fossil-rangeMetamynodon planifrons combines high-set orbits, reduced thoracic neural spines and limb-lever proportions that differ from more terrestrial amynodontids.
claim:taxon:metamynodon:morphologyThe detailed profile is geographically bounded to Orellan channel deposits of Badlands National Park, South Dakota; it is not a complete Asian–North American genus distribution.
claim:taxon:metamynodon:biogeography