Stenobelodon, a new name for a shovel-tusk elephant from North America

[VD231991]

I know many of you aren't very familiar with the alpha-taxonomy of most gomphothere elephants, but Lambert (2023) has erected the new genus Stenobelodon for the amebelodontid gomphothere Amebelodon floridanus based on morphological differences from type species of Amebelodon as well as Konobelodon (which was originally described as a subgenus of Amebelodon but is nowadays seen as a distinct genus). Given that the cheek teeth of the Amebelodon type species is more derived than that of the cheek teeth of Stenobelodon, and because Amebelodon is of slightly younger age than Stenobelodon, the confinement of Amebelodon to North America refines knowledge of shovel-tusked elephant paleobiogeography in the late Miocene because it is apparent that more than one lineage of advanced amebelodontids was present in North America in the late Miocene. Although Lambert notes that the taxa Amebelodon hicksi and A. paladentatus differ from Stenobelodon in having flatter tusks somewhat similar to those of Amebelodon despite being of early Hemphilian age like Stenobelodon, he neglects to reserve final judgment on the possible relationships of these taxa to Amebelodon and Torynobelodon pending future study.

Lambert, W.D., 2023. Implications of discoveries of the shovel-tusked gomphothere Konobelodon (Proboscidea, Gomphotheriidae) in Eurasia for the status of Amebelodon with a new genus of shovel-tusked gomphothere, Stenobelodon. Journal of Vertebrate Paleontology DOI: 10.1080/02724634.2023.2252021 (PDF at ResearchGate)

[Newt]

Very interesting. The paper implies that the shovel-tusked condition arose more than once among gomphotheres, and that different Eurasian shovel-tusked gomphotheres invaded North America at various times. I am curious about what was going on ecologically in the Late Miocene that made this adaptation so useful, and what changed in the Pliocene.