New remains of Eleutherocercus (Xenarthra, Cingulata, Glyptodontidae) from the Pampean and Northwestern regions of Argentina: morphology and phylogeny of late Neogene Doedicurinae

NUÑEZ, A.; MIÑO BOILINI, A. R.; BONINI, R.; BARBOSA,F; TOMASSINI, R.L.; ZURITA, A.E.

Historical Biology

Taylor and Francis

Año: 2023 vol. 35 p. 1274 - 1287

0891-2963

The subfamily Doedicurinae is a monophyletic group of glyptodonts with their own anatomical features andis mostly known on the basis of the Pleistocene genus Doedicurus, one of the largest recorded taxa. The mostdistinctive character of the subfamily, unique within Cingulata, include the absence of ornamentation withlarge foramina, on the exposed surface of the carapace osteoderms. In terminal forms of the late Pleistocene,osteoderms have large foramina which tend to cross the entire thickness. The knowledge of the lateNeogene diversity of the clade, as well as its evolutionary and geographical history, has increased in recentyears, with important records in Argentina, where two late Miocene-Pliocene species are recognised:Eleutherocercus solidus from Catamarca and Tucumán provinces, and Eleutherocercus antiquus from BuenosAires province. The most complete skull of E. antiquus from the early Pliocene Monte Hermoso Formation (ca.5–4.2 Ma) is reported here. The specimen studied shows a conspicuous pathology on the parietal bones, firstreported for fossil cingulates. In addition, the carapace of E. solidus is first described, on the basis of a partiallycomplete specimen from the late Miocene-Pliocene (unknown stratigraphic level) from Tucumán province.Previous phylogenetic hypotheses of the relationships within the Doedicurinae, as well as their relationshipwith the remaining clades of Glyptodontidae, is tested in this study, adding new synapomorphies to thesubfamily. The comparative study suggests that a third species previously proposed (E. paranaensis) from the‘Mesopotamiense’ (late Miocene, Northeastern region of Argentina), must be considered as Eleutherocercussp. Since their oldest record in the late Miocene, the latitudinal distribution of the Doedicurinae seems tohave expanded rapidly reaching middle latitudes, particularly during the Pliocene, but during thePleistocene (particularly the final lapse of this period), they began to retract latitudinally.