INVESTIGADORES
BOND mariano
congresos y reuniones científicas
Título:
PERSISTENCE OF A LINEAGE OF GONDWANAN MAMMALS IN MID-PALEOGENE LEVELS OF WESTERN PATAGONIA
Autor/es:
M.F. TEJEDOR, F.J. GOIN, L. CHORNOGUBSKY, G. LÓPEZ, J.N. GELFO, M. BOND, M.O. WOODBURNE, Y. GUROVICH AND M. REGUERO
Lugar:
San Juan
Reunión:
Congreso; IV Congreso de Paleontología de Vertebrados; 2011
Institución organizadora:
Universidad Nacional de San Juan
Resumen:
PERSISTENCE OF A LINEAGE OF GONDWANAN MAMMALS IN MID-PALEOGENE LEVELS OF WESTERN PATAGONIAM.F. TEJEDOR1,2, F.J. GOIN1, 3, L. CHORNOGUBSKY1,4, G. LÓPEZ1,3, J.N. GELFO1,3, M. BOND1,3, M.O. WOODBURNE5, Y.GUROVICH6 and M. REGUERO1,31Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina2Centro Nacional Patagónico, Blvd. Almirante Brown 2915, U9120ACD Puerto Madryn, Argentina3División Paleontología Vertebrados, Museo de La Plata, Paseo del Bosque s/n, B1900FWA La Plata, Argentina4Sección Paleontología Vertebrados, Museo Argentino de Ciencias Naturales ?Bernardino Rivadavia?, Av. Angel Gallardo 470, C1405DJR Buenos Aires,Argentina5Department of Geology, Museum of Northern Arizona, Flagstaff, AZ 86001 Arizona, USA6School of Biological, Earth and Environmental Sciences, University of New South Wales, New South Wales 2052, Australia.Recently, Tejedor et al. (2009) described a new Paleogene mammalian fauna from levels of the Volcanic-Pyroclastic Complex of the MiddleChubut River. All specimens were recovered from two localities in the vicinity of Paso del Sapo (Chubut Province, Argentina). The specimensdescribed here (LIEB-PV 2000 and LIEB-PV 2001) come from the locality known as La Barda (?26 de Mayo? Farm), with an estimated ageranging between 47?45 Ma (middle Eocene; early Lutetian). They consist of two, probably upper molariform teeth referable to the sametaxon of Gondwanatheria (Mammalia, ?Allotheria). The Gondwanatheria include two families: first, the Sudamericidae Scillato-Yané andPascual, 1985, of hypsodont dentitions, that have been recorded from the Late Cretaceous of Patagonia, Madagascar, India, and possiblyAfrica, as well as from the medial Paleocene of Patagonia and the Eocene of Antarctica. Second, the more generalized, brachydont FerugliotheriidaeBonaparte, 1986, which are only known from the Late Cretaceous of Patagonia (Los Alamitos, La Colonia, and Cerro Tortugalocalities). The new molariform specimens are characterized by: (1) size larger than other Gondwanatheria; (2) molariforms are probablyprotohypsodont, comparable to the earliest Sudamericidae; (3) there are strong transverse crests that alternate with labial furrows; (4) eachtooth has a single root, very short and rounded; (5) the teeth are strongly worn at their occlusal surfaces, and the labial edge is less worn thanthe lingual one. The protohypsodont aspect of the teeth, as well as the strong, transverse crests, suggest affinities with the Sudamericidae; onthe other hand, the occlusal pattern performed by the crests and furrows shows more similarities with the Ferugliotheriidae. If the allocationof the new taxon to this latter family is confirmed, this would extend its biochron approximately 20 Ma, up to the middle Eocene. The newrecord agrees with the known distribution of other gondwanatherians in the southernmost portion of South America (but see Goin et al.,2004). Therefore, it needs to be confirmed whether the distribution of this group in South America included other (Neotropical) areas of thiscontinent or, to the contrary, if it represents an endemic radiation of the Andean Region (Patagonian Subregion) of the Austral Kingdom.Bonaparte, J.F. 1986. Sobre Mesungulatum houusayi y nuevos mamíferos Cretácicos de Patagonia, Argentina. IV Congreso Argentino de Paleontología y Biostratigrafía(Mendoza), Actas 2: 48?61.Goin, F.J., Vieytes, E.C., Vucetich, M.G. Carlini, A.A. and Bond, M.. 2004. Enigmatic Mammal from the Paleogene of Perú. In: K.E. Campbell Jr. (Ed.), ThePaleogene Mammalian Fauna of Santa Rosa, Amazonian Perú. Science Series, Natural History Museum of Los Angeles County 40; 145?153.Scillato-Yané, G. and Pascual, R. 1985. Un peculiar Xenarthra del PaleocenoMedio de Patagonia (Argentina).Su importancia en la sistemática de los Paratheria.Ameghiniana 21: 173?176.Tejedor, M.F., Goin, F.J., Gelfo, J.N., López, G., Bond, M., Carlini, A. A., Scillato-Yané, G. J., Woodburne, M., Chornogubsky, L. Aragón, E., Reguero, M.,Czaplewski, N., Vincon, S., Martin G. M. and Ciancio, M. 2009. New Early Eocene mammalian fauna from Western Patagonia, Argentina. AmericanMuseum Novitates 3638: 1?42.