A NEW SPECIES OF LUTREOLINA THOMAS, 1910 (MARSUPIALIA, DIDELPHIDAE) FROM THE EARLY PLEISTOCENE OF THE SOUTHERN PAMPAS (BUENOS AIRES PROVINCE, ARGENTINA)

GOIN FJ; DE LOS REYES M

PEAPA, Publicación Electrónica de la Asociación Paleontológica Argentina

Asociación Paleontológica Argentina

Lugar: Buenos Aires; Año: 2023 vol. 23 p. 1 - 11

We describe Lutreolina tonnii sp. nov. (Mammalia, Metatheria, Marsupialia, Didelphimorphia, Didelphidae), recovered from Early (or Early–Middle) Pleistocene deposits of the coastal cliffs near Necochea City in Buenos Aires Province, Argentina. Its holotype, a right maxillary with M1-3, indicates that it belongs to the largest species of the genus, including extinct and extant species. It also differs from other species of the genus in having more anteroposteriorly compressed protocones in the upper molars. It differs from the living species in that the maxillary jugal contact is less horizontal in its posterior two-thirds, has a deeper ectoflexus in M3, and has a shallow but distinct internal (lingual) crest linking the bases of stylar cusps B and D in M1-3. The new species is the fourth known up to now for the South American record, and the third for the Plio–Pleistocene of the Pampean Region, thus suggesting a considerable diversity for this genus in mid-latitudes of this continent by the end of the Cenozoic Era.