Autor: |
Abello MA; Laboratorio de Sistemática y Biología Evolutiva (LASBE), Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata. Paseo del Bosque s/n, B1900FWA, La Plata, Argentina.; Email: mabello@fcnym.unlp.edu.ar., De Los Reyes M; División Paleontología Vertebrados, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata. Paseo del Bosque, B1900FWA La Plata, Argentina.; Email: delossreyes@yahoo.com.ar., Candela AM; División Paleontología Vertebrados, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata. Paseo del Bosque, B1900FWA La Plata, Argentina.; Email: acandela@fcnym.unlp.edu.ar., Pujos F; Dpto. de Paleontología, Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales (IANIGLA), CCT-CONICET-Mendoza, Avda.Ruiz Leal s/n, Parque Gral. San Martín, 5500 Mendoza, Argentina.; Email: fpujos@mendoza-conicet.gov.ar., Voglino D; Museo de Ciencias Naturales 'Rvdo. P. Antonio Scasso', Don Bosco 580, San Nicolás de los Arroyos, Buenos Aires, Argentina.; Email: dvoglino@fundacionoga.org.ar., Quispe BM; Departamento de Paleontología , Museo Nacional de Historia Natural , Calle 26 s/n, Cota Cota, La Paz, Bolivia.; Email: bmamaniq@hotmail.com. |
Abstrakt: |
A new species of sparassocynid marsupial, Sparassocynus maimarai n. sp. from the late Miocene of Maimará Formation (Jujuy Province, Argentina) is described from a left mandibular fragment with a complete p2-m4 series. It differs from the remaining species of the genus S. bahiai (Montehermosan-late Miocene/early Pliocene-of Buenos Aires Province, Argentina) and S. derivatus (Chapadmalalan and Marplatan-Pliocene of Buenos Aires Province) by its smaller size, the relatively longer m1 with respect to the m4, the presence of a lingual cingulum extended between para- and metaconid on the m1-3, and its more robust entoconids. As part of this study the taxonomic status of Sparassocynus heterotopicus (Montehermosan, Umala, Bolivia; Pliocene) was reviewed concluding that this taxon should be referred to as 'Sparassocynus' heterotopicus and considered a Didelphoidea of uncertain affinities. Sparassocynus maimarai n. sp. is the oldest records of the genus, adding new information to evaluate the origins and early diversification of sparassocynids. Sparassocynus maimarai n. sp. was recovered with precise stratigraphic control, highlighting its potential biostratigraphic significance to the temporal correlations between Maimará Formation and other Mio-Pliocene stratigraphic units from the northwestern Argentina. |