Alfredo Eduardo Zurita

North American Glyptodontines (Xenarthra, Mammalia) in the Upper Pleistocene of northern South America

The Glyptodontidae is one of the most conspicuous groups in the Pleistocene megafauna of the Americas. The Glyptodontinae were involved in the Great American Biotic Interchange (GABI) and their earliest records in North America are about 3.9 Ma, suggesting an earlier formation of the Panamanian landbridge. Taxonomically it is possible to recognize two Pleistocene genera of Glyptodontinae:Glyptodon (ca. 1.8 – 0.008 Ma), restricted to South America, andGlyptotherium (ca. 2.6 – 0.009 Ma), including records in both North and Central America. Here we present the first report of the genusGlyptotherium in South America, from the Late Pleistocene of several fossil localities in Falcón State, northwestern Venezuela. A comparative analysis of the material, represented by cranial and postcranial parts, including the dorsal carapace and caudal rings, suggests a close affinity withGlyptotherium cylindricum (Late Pleistocene of Central Mexico). This occurrence in the latest Pleistocene of the northernmost region of South America Supports the bidirectional faunal migration during the GABI and the repeated re-immigration from North America of South American clades, as has been reported in other members of the Cingulata (e.g., Pampatheriidae).KurzfassungDie Glyptodontidae ist eine der auffälligsten Faunengruppen des Pleistozäns Südamerikas. Die Glyptodontinae waren in dem „Great American Biotic Interchange“ (GABI) involviert, und ihre frühesten Reste aus Nordamerika sind etwa 3,9 Ma alt, was für eine frühere Entstehung der Panamanischen Landbrücke spricht. Es ist taxonomisch möglich, zwei Genera von pleistozänen Glyptodontinae zu unterscheiden:Glyptodon (ca. 1,8–0,008 Ma) aus Südamerika undGlyptotherium (ca. 2,6 – 0,009 Ma) aus Nord- und Mittelamerika. Hier stellen wir den ersten Nachweis vonGlyptotherium in Südamerika, aus dem oberen Pleistozän von verschiedenen Lokalitäten des Bundesstaates Falcón, nordwestliches Venezuela, vor. Eine vergleichende Untersuchung von Schädel- und Postkranialelementen, einschließlich des dorsalen Panzers und kaudaler Ringe, unterstützt eine nahe Verwandtschaft mitGlyptotherium cylindricum (Spätes Pleistozän Mittel-Mexikos). Diese spät-pleistozäne Verbreitung im nördlichsten Teil Südamerikas ist ein Nachweis für eine bidirektionale Migration während des GABI und für das Zurückkehren von Taxa von Nordamerika nach Südamerika, wie schon für andere Vertreter der Cingulata (z. B. Pampatheriidae) berichtet wurde.

New Glyptodont from the Codore Formation (Pliocene), Falcón State, Venezuela, its relationship with theAsterostemma 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 Patagonia.KurzfassungEine der basalen Gruppen der Glyptodontidae stellen die Propalaehoplophorinae (spätes Oligozän — mittleres Miozän) dar, deren Gattungen (Propalaehoplophorus, Eucinepeltus, Metopotoxus, Cochlops undAsterostemma) man zuerst aus dem argentinischen Patagonien kannte. Darunter istAsterostemma durch eine weite latitudinale Verbreitung gekennzeichnet, welche sich vom südlichsten (Patagonien) zum nördlichsten (Kolumbien, Venezuela) Südamerika erstreckt. Allerdings wurde die Gattungszugehörigkeit der miozänen Arten Kolumbiens und Venezuelas (A.? acostae, A. gigantea undA. venezolensis) von einigen Autoren angezweifelt, die explizit die Möglichkeit in Betracht zogen, dass diese Taxa einer anderen Gattung angehören, die sich von der Gattung der südlichen Breiten unterscheidet. Ein neuer Vergleich der Taxa aus Patagonien, Kolumbien und Venezuela (zusammen mit einer neuen Gattung und Art aus dem Pliozän Venezuelas) zeigt, dass die Arten aus dem nördlichen Südamerika nicht zu den Propalaehoplophorinae gehören, sondern die ersten Stufen in der Kladogenese der glyptodontinen Glyptodontidae darstellen. Deren Geschichte war bislang auf das späte Miozän — frühe Holozän des südlichsten Südamerikas beschränkt. Dementsprechend stellen wir hier die neue GattungBoreostemma für die Arten des nördlichen Südamerikas auf;Asterostemma wird auf das Miozän Patagoniens beschränkt. Die Datenlage deutet somit darauf hin, dass Glyptodontinae sich tatsächlich im nördlichsten Teil Südamerikas entwickelten. Ihr Auftreten in den südlichen Gebieten fällt mit dem Höhepunkt des „Zeitalters der südlichen Ebenen“ zusammen. Die Verbreitung der Propalaehoplophorinae wird geographisch auf Patagonien beschränkt.

Mamíferos extintos del Cuaternario de la Provincia del Chaco (Argentina) y su relación con aquéllos del este de la región pampeana y de Chile

Se da a conocer un conjunto de restos oseos de mamiferos pleistocenos provenientes de distintas localidades de la Provincia del Chaco, Argentina. El conjunto esta integrado por Glyptodon sp., Neosclerocalyptus cf. N. heusseri, Panochthus sp., Propraopus grandis, Megatherium cf. M. americanum, Megatherium sp., Scelidotherium cf. S. leptocephalum, Lestodon sp., Equus (Amerhippus) neogeus, Toxodon cf. T. gezi y Toxodon sp., Smilodon populator, Morenelaphus sp., Stegomastodon cf. S. platensis, Stegomastodon sp. La asociacion es referible al Bonaerense-Lujanense (Pleistoceno medio- Holoceno temprano). Desde el punto de vista paleozoogeografico muestra gran similitud con aquellas de igual antiguedad de la region pampeana, de la Provincia de Formosa, Paraguay y sudeste de Bolivia. Estas similitudes son atribuidas a una marcada homogeneidad ambiental. Por otro lado, una comparacion preliminar con la paleomastofauna de Chile indica algunas diferencias significativas, fundamentalmente con respecto a la region central, mientras que hacia el sur y norte se observan mayores similitudes con la paleofauna cuaternaria de Argentina.

The most complete known Neogene Glyptodontidae (Mammalia, Xenarthra, Cingulata) from northern South America: taxonomic, paleobiogeographic, and phylogenetic implications

ABSTRACT The knowledge of northern South American Glyptodontidae (Mammalia, Xenarthra, Cingulata) is very scarce compared with that of southern South American taxa, which have been systematically studied since the 19th century. Recently, the northern taxa (originally assigned to the Glyptodontidae Propalaehoplophorinae Asterostemma and Propalaehoplophorus) have been reinterpreted as basal Glyptodontinae, belonging to the new genus Boreostemma. In this contribution, we present and describe the most complete Neogene Glyptodontidae from northern South America (middle Miocene of the Honda Group, La Venta, Colombia), and its main taxonomic, paleobiogeographic, and phylogenetic implications. This new material expands the morphological characterization of B. acostae and corroborates differences compared with Glyptodontidae from Miocene southern South America. A cladistic analysis corroborates the monophyly of the Glyptodontinae, that B. acostae and B. venezolensis being the sister group of the remaining taxa of Glyptodontinae. The traditionally recognized genera (e.g., Glyptodon and Glyptotherium) constitute natural groups. Whereas the Miocene seems to represent a diversification period for Glyptodontidae in southern South America, the recorded taxa in northern South America are restricted with certainty only to the Glyptodontinae Boreostemma.

A review of the Quaternary Tayassuidae (Mammalia, Artiodactyla) from the Tarija Valley, Bolivia

Three genera of Tayassuidae are recognized in South America: Platygonus Le Conte, 1848, Catagonus Ameghino, 1904 and Tayassu Fischer, 1814. This study provides the first systematic review of the Pleistocene tayassuids yet reported from Bolivia. The richest records of the family in South America derived from central-eastern Argentina and southern Brazil. Catagonus stenocephalus (Lund in Reinhardt, 1880) is documented for the first time in Bolivia, significantly extending the geographic distribution of this species in South America. We cannot confirm the validity of Platygonus tarijensis (Ameghino, 1904), but accept its generic allocation. Both taxa show adaptations to arid or semi-arid and relatively open environments, which is consistent with the palaeoenvironmental conditions previously proposed for the Tarija Valley. The veracity of other records of the family from Bolivia cannot be confirmed.

Galea (Rodentia, Caviidae) in the late Pleistocene of Corrientes Province (Argentina): taxonomic and paleobiogeographic implications

Fil: Francia, Analia. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. Division Paleontologia Vertebrados; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas; Argentina

First record of Scelidodon chiliense (LYDEKKER) (Phyllophaga, Scelidotheriinae) from the Lujanian Stage (Late Pleistocene - Early Holocene) of Argentina

Fil: Mino Boilini, Angel Ramon. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Nordeste. Centro de Ecologia Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecologia Aplicada del Litoral; Argentina

First Neogene skulls of Doedicurinae (Xenarthra, Glyptodontidae): morphology and phylogenetic implications

Among Glyptodontidae, Doedicurinae (late Miocene–early Holocene) includes the glyptodonts with the largest size and latest records. Doedicurinae is mainly characterised by a smooth surface of the osteoderms with large foramina, and a particular morphology of the caudal tube. All taxa except one (Doedicurus clavicaudatus) have been recognised and characterised on the basis of remains of caudal tubes and/or dorsal carapaces. This situation produced an evident overestimation of the real diversity of this group, and a taxonomic revision is needed. In fact, no Neogene skulls were known. We present and describe the first two Neogene skulls belonging to Doedicurinae (cf. Eleutherocercus antiquus). The materials come from the El Polvorín and Chapadmalal Formations, in the surroundings of Olavarría and Mar del Plata localities, respectively (Buenos Aires province, Argentina). A cladistic analysis was carried out in order to situate these materials among Glyptodontidae and inferring new synapomorphies at skull level in Doedicurinae. Cf. Eleutherocercus antiquus clusters with the Pleistocene species Doedicurus clavicaudatus showing three unambiguous synapomorphies, which in turn represents the first skull synapomorphies for Doedicurinae. Finally, the presence of cf. Eleutherocercus antiquus in the El Polvorín and Chapadmalal Formations suggests that the stratigraphic distribution of this species could include the Montehermosan–Chapadmalalan interval.

The earliest record of Neuryurus Ameghino (Mammalia, Glyptodontidae, Hoplophorinae)

Zurita, A.E., Soibelzon, E., Scillato-Yané, G.J. & Cenizo, M., March, 2009. The earliest record of Neuryurus Ameghino (Mammalia, Glyptodontidae, Hoplophorinae). Alcheringa 33, 49–57. ISSN 0311-5518. Among the Pleistocene Cingulata (Glyptodontidae), Neuryurus Ameghino is poorly documented; the only well-characterized species being N. rudis (Gervais), limited to the Ensenadan Age/Stage (early-middle Pleistocene) of the Pampean region in Argentina. The genus is characterized by dorsal carapace osteoderms with uniformly punctate exposed surfaces giving them a rugose, almost spongy aspect; sutures between the osteoderms are loose. Outside Argentina, Neuryurus has been recorded in western Uruguay and southern Brazil. Until now, its temporal range was restricted to the Ensenadan-Lujanian (early Pleistocene–early Holocene). In this context, we present the earliest record of the genus from the San Andrés Formation (Sanandresian Substage; late Pliocene), consisting of dorsal carapace osteoderms and caudal rings and sheath. Most of the associated fauna indicates a dry climate and the assemblage probably characterizes a cold arid event detected at around 2.5 Ma.

First evidence of scavenging of a Glyptodont (Mammalia, Glyptodontidae) from the Pliocene of the Pampean region (Argentina): taphonomic and paleoecological remarks

The Cingulata Glyptodontidae (Xenarthra) are one of the most conspicuous Cenozoic herbivore clades in South America reaching North America during the Great American Biotic Interchange. The evidence of predation on these large armoured mammals is very scarce and limited to a Pliocene skull (Glyptotherium) in North America and some latest Pleistocene-early Holocene specimens in South America, with signals of human consumption. In this contribution, we present the first case of scavenging on a glyptodont belonging to cf. Eosclerocalyptus lineatus (Hoplophorini) from the Pliocene of the Pampean region (Argentina). In addition, we analyze the potential scavengers and the paleoenvironmental context in which this occurred. The evidence suggests that: a) the carcass was covered by a shallow water body, probably an abandoned channel; b) the carcass was completely covered during a brief lapse of time, probably less than a year; c) the morphology of the bite marks clearly coincide with the dentition of the procyonid Chapalmalania (Mammalia, Procyonidae), thus corroborating some presumptions about the paleoautoecological trends of this taxon. Martín de los Reyes. Facultad de Ciencias Naturales y Museo de La Plata. Paseo del Bosque s/n (1900), La Plata, Buenos Aires, Argentina delossreyes@yahoo.com.ar Daniel Poiré. CIG de Investigaciones Geológicas, UNLP-CONICET, Calle 1 No 644, 1900 La Plata, Argentina dpoire@gmail.com Leopoldo Soibelzon. División Paleontología de Vertebrados, Facultad de Ciencias Naturales y Museo (UNLP). Paseo del Bosque s/n, 1900, La Plata, Buenos Aires, Argentina lsoibelzon@fcnym.unlp.edu.ar Alfredo E. Zurita. Centro de Ecología Aplicada del Litoral (CECOAL-CONICET) y Universidad Nacional del Nordeste. Ruta 5, km. 2,5, 3400, CC 128 Corrientes, Argentina azurita@cecoal.com.ar M.J. Arrouy. CIG de Investigaciones Geológicas, UNLP-CONICET, Calle 1 No 644, 1900 La Plata, Argentina marouy@gmail.com