The Megatheriinae (Xenarthra, Tardigrada) from the Tertiary of Entre Ríos, Argentina: taxonomic and systematic aspects

La subfamilia Megatheriinae ha sido registrada desde el Colloncurense (Mioceno medio) hasta el Lujanense (Pleistoceno tardío-Holoceno temprano). Aquí se presenta un resumen del estado del conocimiento de los megaterinos de la Formación Ituzaingó de la provincia de Entre Ríos. La diversidad de Megatheriinae de dicha unidad es mayor que la de cualquier otra de Argentina. Sin embargo, la naturaleza de los depósitos, y el carácter fragmentario y disociado de los restos sobre los cuales fueron reconocidas las especies, ha generado una sobrestimación del número de taxones presentes en esta formación. Se concluye que hubo dos “grupos” de megaterinos en el “Conglomerado osífero” de la Formación Ituzaingó: 1) formas de pequeño a mediano tamaño, representadas por Promegatherium smaltatum Ameghino, Pliomegatherium lelongi Kraglievich y Eomegatherium nanum (Burmeisker); y 2) formas de mayor talla, representadas por Pyramiodontherium sp.The subfamily Megatheriinae has been recorded from the Colloncuran (Middle Miocene) to the Lujanian (Late Pleistocene-Early Holocene). A summary of the present state of knowledge of the megatheriines of the Ituzaingó Formation of Entre Ríos Province is given. The diversity of Megatheriinae of the aforementioned unit is higher than that of any other in Argentina. However, the nature of the deposits and the fragmentary and dissociated nature of the remains on which the species were recognized, have led to an overestimation of the diversity in this formation. We conclude that there were two “groups” of megatheriines in the “Conglomerado osífero” of the Ituzaingó Formation: 1) small to middle sized forms, represented by Promegatherium smaltatum Ameghino, Pliomegatherium lelongi Kraglievich and Eomegatherium nanum (Burmeisker); and 2) larger forms, represented by Pyramiodontherium sp.Facultad de Ciencias Naturales y Muse

A new species of Neosclerocalyptus Paula Couto, 1957 (Xenarthra, Glyptodontidae, Hoplophorinae) from the middle Pleistocene of the Pampean region, Argentina

A new species of the genus Neosclerocalyptus Paula Couto, 1957 (= SclerocalyptusAmeghino, 1891), N. gouldi n. sp. (Cingulata, Glyptodontidae, Hoplophorini) is described. Th is new taxon, comes from the Bonaerian Stage (middle Pleistocene; c. 0.4-0.13 Ma) of San Andrés de Giles, Buenos Aires province, Argentina. Th e type consists mainly of an associated skull, mandible and cephalic shield in an excellent state of preservation. Morphological characters that distinguish the species include: a) lesser pneumatization and lateral expansion of fronto-nasal sinuses compared to N. paskoensis; b) descending processes of maxillaries and zygomatic arches very robust and with marked ridges; c) lower third of descending processes markedly inclined toward the sagittal plane; d) inclination of the parieto-occipital skull region inter-mediate between those of Ensenadan and Lujanian forms; e) infraorbital fora mina larger than in N. paskoensis, similar in size to those of N. ornatus; and f ) occipital area less expanded laterally than in N. paskoensis. Th is new taxon completes the chronological distribution of genus Neosclerocalyptus which, until now, included two well-characterized species for the Ensenadan (early Pleistocene: N. pseudornatus and N. ornatus) and one Lujanian (late Pleistocene-early Holocene: N. paskoensis). Th e Bonaerian species, N. migoyanus, recognized by Ameghino, should be considered as a nomen dubium,due to the lack of diagnostic characters.Une nouvelle espèce de Neosclerocalyptus Paula Couto, 1957 (Xenarthra, Glyptodon-tidae, Hoplophorinae) du Pléistocène moyen de la région pampéenne d’Argentine.Une nouvelle espèce du genre Neosclerocalyptus Paula Couto, 1957 (= Sclero-calyptus Ameghino, 1891), N. gouldi n. sp. (Cingulata, Glyptodontidae, Hoplo-phorini), est décrit. Ce taxon nouveau vient de l’Étage Bonaériéen (Pleistocène moyen ; c. 0.4-0.13 Ma) de San Andrés de Giles, province de Buenos Aires, Argentine. Le spécimen est représenté par un crâne, une mandibule et un bou-clier céphalique associés, excellent état de préservation. Les caractéristiques morphologiques qui distinguent l’espèce incluent : a) une pneumatisation et une expansion latérale des sinus fronto-nasaux moindres par rapport à N. pasko-ensis ; b) des processus descendants des arches maxillaires et zygomatiques très robustes et avec des dorsales marquées ; c) le tiers inférieur des processus des-cendants incliné de manière marquée vers le plan sagittal ; d) une inclinaison de la région crânienne pariéto-occipitale intermédiaire entre celles des formes ensénadéennes et lujanéennes ; e) des foramens infraorbitaux plus grands que chez N. paskoensis, de même longueur que ceux de N. ornatus ; et f ) une région occipitale moins développée latéralement que chez N. paskoensis. Ce nouveau taxon complète la distribution chronologique du genre Neosclerocalyptus, qui, jusqu’à présent, incluait deux espèces bien caractérisées propres à l’Ensénadéen (Pleistocène inférieur : N. pseudornatus et N. ornatus) et une autre limitée au Lujanéen (Pleistocène supérieur-Holocène inférieur : N. paskoensis). L’espèce bonaériéenne, N. migoyanus, reconnue par Ameghino doit être considérée comme un nomen dubium, par son manque de caractères diagnostiquesFacultad de Ciencias Naturales y Muse

An enigmatic and large-sized specimen of Panochthus (Glyptodontidae, “Panochthini”) from the Ensenadan (Early-Middle Pleistocene) of the Pampean region, Argentina

AbstractPanochthus Burmeister (Mammalia, Xenarthra, Glyptodontidae) is one of the best characterized Pleistocene genera. It is possible to recognize 2 Ensenadan (Early-Middle Pleistocene) species from the Pampean region of Argentina and Bolivia, Panochthus intermedius Lydekker and P. subintermedius Castellanos, whereas 2 species are considered as valid for the age Bonaerian-Lujanian (Middle Pleistocene-Late Pleistocene), namely P. tuberculatus Owen and P. frenzelianus Ameghino. This paper provides the first record of a skull belonging to Panochthus from Ensenadan deposits in the Pampean Region of Argentina, being the second record for the genus in this lapse. The synapomorphies that support this taxonomic interpretation are: a frontal-ventrally inclined nasal zone forming a 45° angle between the palate plane and the plane of the upper rostral zone; a cranial length/height ratio that less than 1% of the height, without considering the descending processes of the zygomatic arch; external nasal openings with a fronto-ventral orientation. A comparative study with P. intermedius and other species from the Bonaerian-Lujanian refutes its placement among any of these; on the other hand, no cranial materials are known for the other species from the Ensenadan (P. subintermedius). Considering that the former is a large species, and that this skull corresponds undoubtedly to a species of Panochthus of large dimensions, the most parsimonious taxonomic hypothesis is to tentatively assign the material MLP 84-IX-2-11 to Panochthus cf. subintermedius. Future findings of more complete materials would provide support or refute this hypothesis

Un gigantesco gliptodonte en los alrededores de la ciudad de La Plata

Descubrimientos paleontológicos realizados en los últimos años en la cantera de Hernández, nos permiten ampliar el conocimiento de la notable fauna de mamíferos que vivió en los alrededores de lo que hoy es la ciudad de La Plata. Entre ellos se destaca un gliptodonte que, reconstruido, mide unos 4,20 m de largo y 1,40 m de altura; es una de las más gigantescas especies conocidas del grupo y vivió hace 780.000 años.Fundación Museo La Plat

Los xenarthra de gran barranca : más 20 ma de historia

Fil: Carlini, Alfredo Armando. Departamento de Paleontología de Vertebrados, Facultad de Ciencias Naturales y Museo de La Plata, Paseo del Bosaque s/n,1900 La Plata, ArgentinaFil: Ciancio, Martín Ricardo. Departamento de Paleontología de Vertebrados, Facultad de Ciencias Naturales y Museo de La Plata, Paseo del Bosaque s/n,1900 La Plata, ArgentinaFil: Scillato-Yané, Gustavo Juan. Departamento de Paleontología de Vertebrados, Facultad de Ciencias Naturales y Museo de La Plata, Paseo del Bosaque s/n,1900 La Plata, Argentin

Un gigantesco gliptodonte en los alrededores de la ciudad de La Plata

Descubrimientos paleontológicos realizados en los últimos años en la cantera de Hernández, nos permiten ampliar el conocimiento de la notable fauna de mamíferos que vivió en los alrededores de lo que hoy es la ciudad de La Plata. Entre ellos se destaca un gliptodonte que, reconstruido, mide unos 4,20 m de largo y 1,40 m de altura; es una de las más gigantescas especies conocidas del grupo y vivió hace 780.000 años.Fundación Museo La Plat

A new species of Neosclerocalyptus Paula Couto, 1957 (Xenarthra, Glyptodontidae, Hoplophorinae) from the middle Pleistocene of the Pampean region, Argentina

A new species of the genus Neosclerocalyptus Paula Couto, 1957 (= SclerocalyptusAmeghino, 1891), N. gouldi n. sp. (Cingulata, Glyptodontidae, Hoplophorini) is described. Th is new taxon, comes from the Bonaerian Stage (middle Pleistocene; c. 0.4-0.13 Ma) of San Andrés de Giles, Buenos Aires province, Argentina. Th e type consists mainly of an associated skull, mandible and cephalic shield in an excellent state of preservation. Morphological characters that distinguish the species include: a) lesser pneumatization and lateral expansion of fronto-nasal sinuses compared to N. paskoensis; b) descending processes of maxillaries and zygomatic arches very robust and with marked ridges; c) lower third of descending processes markedly inclined toward the sagittal plane; d) inclination of the parieto-occipital skull region inter-mediate between those of Ensenadan and Lujanian forms; e) infraorbital fora mina larger than in N. paskoensis, similar in size to those of N. ornatus; and f ) occipital area less expanded laterally than in N. paskoensis. Th is new taxon completes the chronological distribution of genus Neosclerocalyptus which, until now, included two well-characterized species for the Ensenadan (early Pleistocene: N. pseudornatus and N. ornatus) and one Lujanian (late Pleistocene-early Holocene: N. paskoensis). Th e Bonaerian species, N. migoyanus, recognized by Ameghino, should be considered as a nomen dubium,due to the lack of diagnostic characters.Une nouvelle espèce de Neosclerocalyptus Paula Couto, 1957 (Xenarthra, Glyptodon-tidae, Hoplophorinae) du Pléistocène moyen de la région pampéenne d’Argentine.Une nouvelle espèce du genre Neosclerocalyptus Paula Couto, 1957 (= Sclero-calyptus Ameghino, 1891), N. gouldi n. sp. (Cingulata, Glyptodontidae, Hoplo-phorini), est décrit. Ce taxon nouveau vient de l’Étage Bonaériéen (Pleistocène moyen ; c. 0.4-0.13 Ma) de San Andrés de Giles, province de Buenos Aires, Argentine. Le spécimen est représenté par un crâne, une mandibule et un bou-clier céphalique associés, excellent état de préservation. Les caractéristiques morphologiques qui distinguent l’espèce incluent : a) une pneumatisation et une expansion latérale des sinus fronto-nasaux moindres par rapport à N. pasko-ensis ; b) des processus descendants des arches maxillaires et zygomatiques très robustes et avec des dorsales marquées ; c) le tiers inférieur des processus des-cendants incliné de manière marquée vers le plan sagittal ; d) une inclinaison de la région crânienne pariéto-occipitale intermédiaire entre celles des formes ensénadéennes et lujanéennes ; e) des foramens infraorbitaux plus grands que chez N. paskoensis, de même longueur que ceux de N. ornatus ; et f ) une région occipitale moins développée latéralement que chez N. paskoensis. Ce nouveau taxon complète la distribution chronologique du genre Neosclerocalyptus, qui, jusqu’à présent, incluait deux espèces bien caractérisées propres à l’Ensénadéen (Pleistocène inférieur : N. pseudornatus et N. ornatus) et une autre limitée au Lujanéen (Pleistocène supérieur-Holocène inférieur : N. paskoensis). L’espèce bonaériéenne, N. migoyanus, reconnue par Ameghino doit être considérée comme un nomen dubium, par son manque de caractères diagnostiquesFacultad de Ciencias Naturales y Muse

Ameghino y el positivismo cientificista argentino: una filosofía original

En este articulo, los autores, luego de reseñar la situación de la ciencia en tiempos de Ameghino, sostienen que las ideas filosóficas del sabio argentino ostentan ciertos rasgos que se distinguen del positivismo europeo y determinan su originalidad. Esos rangos constituyen, en particular, un "materialismo ortológico", según el cual todo -incluso el espíritu- surge de la materia y un "finalismo espiritualista", que prevé la perfección futura del espíritu humano.In this paper the authors, after reviewing the status of science in Anieghino's time, sustain that his philosophical ideas show some features which stay apart from the European positivism. These are: ontological materialism, according to which everything, the spirit is included, arises from matter; final spiritualism, which announces the future spiritual perfection of the human being.Facultad de Ciencias Naturales y Muse

New Glyptodont from the Codore Formation (Pliocene), Falcón State, Venezuela, its relationship with the Asterostemma problem, and the paleobiogeography of the Glyptodontinae

One of the basal Glyptodontidae groups is represented by the Propalaehoplophorinae (late Oligocene — middle Miocene), whose genera (Propalaehoplophorus, Eucinepeltus, Metopotoxus, Cochlops, andAsterostemma) were initially recognized in Argentinian Patagonia. Among these,Asterostemma was characterized by its wide latitudinal distribution, ranging from southernmost (Patagonia) to northernmost (Colombia, Venezuela) South America. However, the generic assignation of the Miocene species from Colombia and Venezuela (A.? acostae, A. gigantea, andA. venezolensis) was contested by some authors, who explicitly accepted the possibility that these species could correspond to a new genus, different from those recognized in southern areas. A new comparative study of taxa from Argentinian Patagonia, Colombia and Venezuela (together with the recognition of a new genus and species for the Pliocene of the latter country) indicates that the species in northern South America are not Propalaehoplophorinae, but represent the first stages in the cladogenesis of the Glyptodontinae glyptodontids, the history of which was heretofore restricted to the late Miocene — early Holocene of southernmost South America. Accordingly, we propose the recognition of the new genusBoreostemma for the species from northern South America and the restriction ofAsterostemma to the Miocene of Patagonia. Thus, the available data indicate that the Glyptodontinae would in fact have arisen in the northernmost regions of this continent. Their arrival to more southerly areas coincides with the acme of the "Age of Southern Plains”. The Propalaehoplophorinae are geographically restricted to Patagoni

A peculiar new Pampatheriidae (Mammalia: Xenarthra: Cingulata) from the Pleistocene of Argentina and comments on Pampatheriidae diversity

Pampatheriidae are a group of cingulates native to South American that are known from the middle Miocene to the lower Holocene. Two genera have been recognized between the lower Pleistocene and the lower Holocene: Pampatherium Gervais and Ameghino (Ensenadan, Bonaerian and Lujanian, lower Pleistocene-lower Holocene) and Holmesina Simpson (Blancan, Irvingtonian, upper Pliocene-lower Holocene). They have been mainly differentiated by their osteoderm morphology and cranio-dental characters. These taxa had a wide latitudinal distribution, extending from the southern part of South America (Península Valdés, Argentina) to North America (Florida, USA). In this contribution, we describe a new genus and species of Pampatheriidae for the lower and middle Pleistocene of Buenos Aires Province and for the upper Pleistocene of Santa Fe Province (Argentina).The new taxon is represented by disarticulated osteoderms, one skull element, two thoracic vertebrae and a right femur and patella. It has extremely complex osteoderm ornamentations and particular morphological characters of the cranial element and femur that are not found in any other species of the family. This new taxon, recorded in the lower-middle Pleistocene (Ensenadan Stage/Age) and in the upper Pleistocene-early Holocene (Lujanian Stage/Age), is incorporated to the Pleistocene mammal assemblage of South America. Finally, the Pampatheriidae diversity is greater during the Lujanian Stage/Age than the Ensenadan Stage/Age.Facultad de Ciencias Naturales y Muse