Data from: First record of Toxodontidae (Mammalia, Notoungulata) from the late Miocene–early Pliocene of the southern central Andes, NW Argentina

A new species of toxodontid notoungulate, Xotodon maimarensis n. sp., is
described from the Maimará Formation (late Miocene–early Pliocene), Jujuy
Province, northwestern Argentina. This is the first record of a toxodontid
from the Eastern Cordillera. The specimen is housed at the Museo de
Geología, Mineralogía y Paleontología, Instituto de Geología y Minería de
la Universidad Nacional de Jujuy. It consists of an incomplete mandible
preserving the right mandibular ramus with part of the dental series,
partially preserved symphysis with all the incisors, and a small portion
of the left ramus without teeth. The following characters distinguish it
as a new taxon: symphysis long and narrow with slight divergence of its
lateral borders; strong procumbence of lower incisors and deeply implanted
i3; chin angle lower than in X. major and X. cristatus and bulging labial
keel limiting strong lateral concavities. Comparative analysis in the
context of the recently revised Neogene Toxodontidae indicates that the
Maimará specimen shares mandibular features and dental characters with
Xotodon and Mixotoxodon, differing from the latter by the more upraised
symphysis. The phylogenetic position of Xotodon maimarensis n. sp.
supports the taxonomic interpretation of the studied specimen as a new
species of Xotodon. This new Toxodontidae increases the knowledge of the
diversity and radiation of this group of notoungulates in northwest
Argentina.