 |
| Megadolodus molariformis McKenna, 1956 in Wilson, Carrillo, Salas-Gismondi, Antoine, Benites-Palomino, Condamine, Marivaux, Pujos, Sánchez-Meseguer et Saarinen, 2024. Reconstruction by Miguel Hernandez. |
ABSTRACT
Megadolodinae is a clade of tropical bunodont litopterns that includes three previously recognized species from Miocene fossil sites from northern South America. Here, we report an additional occurrence of Megadolodus molariformis from the Middle Miocene exposures at the Fitzcarrald arch (Peruvian Amazonia), based on dental material, which represents the southernmost record of the clade. This discovery further increases the faunal similarity between Fitzcarrald and the coeval La Venta fauna of Colombia. Given the convergent evolution of the bunodont dentition of megadolodines with suoids (Old World pigs and New World peccaries), we tested the hypothesis of frugivory in megadolodines with a mesowear angle approach using modern pigs and peccaries. These analyses differentiate the diet of modern suoids and suggest that megadolodines had a more abrasive diet than most of these taxa, except for the grazing warthogs. The dentition of megadolodines shows similar levels of abrasion to modern babirusas, thereby suggesting that the latter may represent an appropriate modern analog.
Class MAMMALIA Linnaeus, 1758
Infraclass PLACENTALIA Owen, 1837
Order LITOPTERNA Ameghino, 1889
Family PROTEROTHERIIDAE Ameghino, 1887
Subfamily MEGADOLODINAE Cifelli & Villarroel, 1997
Genus MEGADOLODUS McKenna, 1956
MEGADOLODUS MOLARIFORMIS McKenna, 1956
 |
| A–F. Megadolodus molariformis upper dentition. A–D. Megadolodus molariformis right M1 (MUSM 4963) from the URU-208 locality of the Fitzcarrald Local Fauna in A, occlusal, B, buccal, C, distal, and D, mesial views, respectively. E, UNC TATAC1, right maxilla with P4–M3. F, VPPLT 1588, left maxilla with M1–3. G, map of the occurrences of Megadolodinae in northern South America. Megadolodus molariformis silhouette from phylopic.org (Zimices/Julián Bayona, CC BY 3.0 DEED). Scale bar equals 10 mm. |
 |
| Artistic reconstruction of Megadolodus molariformis from the Middle Miocene URU-208 locality of the Fitzcarrald Local Fauna. Reconstruction by Miguel Hernandez. |
CONCLUSION:
We describe a bunodont upper molar from the late Middle Miocene Fitzcarrald Local Fauna of Peruvian Amazonia as belonging to the proterotheriid megadolodine Megadolodus molariformis (Fig. 4). This record further increases the faunal similarity between Fitzcarrald and other Middle Miocene faunas from Western Amazonia, including La Venta (Colombia) and TAR-31 (Tarapoto area, Peru). This similarity increases the confidence in assignment of the fauna of the Fitzcarrald arch to the Laventan stage.
...
Oscar E. Wilson, Juan D. Carrillo, Rodolfo Salas-Gismondi, Pierre-Olivier Antoine, Aldo Benites-Palomino ,Fabien L. Condamine, Laurent Marivaux, François Pujos, Andrea Sánchez-Meseguer and Juha Saarinen. 2024. Southernmost Record of Megadolodus (Litopterna, Proterotheriidae, Megadolodinae) from the late Middle Miocene of Fitzcarrald, Peruvian Amazonia, and mesowear analysis of diet in megadolodine litopterns. Journal of Vertebrate Paleontology. e2413103. DOI: doi.org/10.1080/02724634.2024.2413103
