The most ancient caviine rodent (Hystricognathi, Cavioidea) comes from the late Miocene of Northwest Argentina (South America)

2016 ◽  
Vol 29 (3) ◽  
pp. 376-383 ◽  
Author(s):  
María Carolina Madozzo-Jaén ◽  
María Encarnación Pérez
Keyword(s):  
South America ◽  
Late Miocene ◽  
Northwest Argentina

A new argyrolagoid (Mammalia: Marsupialia) from the middle Miocene of Bolivia

1988 ◽  
Vol 62 (3) ◽  
pp. 463-467 ◽  
Author(s):  
Villarroel A. Carlos ◽  
Larry G. Marshall
Keyword(s):  
South America ◽  
Late Miocene ◽  
Adaptive Radiation ◽  
Middle Miocene ◽  
Northwest Argentina ◽  
The Family ◽  
Size And Structure

A new argyrolagoid marsupial, Hondalagus altiplanensis n. gen., n. sp., from the middle Miocene (Santacrucian–Friasian) age locality of Quebrada Honda in southernmost Bolivia represents the smallest and most specialized member of the family Argyrolagidae known. The lower molars are hypselodont and lack vertical grooves labially and lingually, and M4 is greatly reduced relative to M3. In overall size and structure, H. altiplanensis compares best with Microtragulus catamarcensis (Kraglievich, 1931) from rocks of late Miocene (Huayquerian) age in northwest Argentina. Hondalagus altiplanensis demonstrates that the adaptive radiation of argyrolagoids was much greater than previously envisioned, and that generic differentiation of known taxa occurred no later than early–middle Miocene time in South America.

Spatiotemporal palaeodiversity patterns of modern crocodiles (Crocodyliformes: Eusuchia)

2019 ◽  
Vol 189 (2) ◽  
pp. 635-656 ◽  
Author(s):  
Ane De Celis ◽  
Iván Narváez ◽  
Francisco Ortega
Keyword(s):  
South America ◽  
Least Squares ◽  
Late Miocene ◽  
North American ◽  
Fossil Record ◽  
Generalized Least Squares ◽  
Global Scale ◽  
Biotic Factors ◽  
Species Dynamics ◽  
Over Time

Abstract Eusuchia is a crocodyliform clade with a rich and diverse fossil record dating back to the Mesozoic. There are several recent studies that analyse crocodyliform palaeodiversity over time, but none of them focuses exclusively on eusuchians. Thus, we estimated subsampled eusuchian palaeodiversity species dynamics over time not only at a global scale, but also by continents and main crocodylian lineages (Alligatoroidea, Crocodyloidea and Gavialoidea). These estimates reveal complex spatiotemporal palaeodiversity patterns, in which two maxima can be detected: the first during the Palaeocene and the second, which is also the biggest, in the middle-late Miocene. The Palaeocene shift is related to a North American alligatoroid diversification, whereas the middle–late Miocene maximum is related to a diversification of the three main Crocodylia lineages in Gondwanan land masses, but especially in South America. Additionally, a model-based study using generalized least squares was carried out to analyse the relationships between different abiotic and sampling proxies and eusuchian palaeodiversity. The results show that palaeotemperature is the most important factor amongst the analysed proxies, in accordance with previous studies. However, the results suggest that, along with palaeotemperature, other abiotic and/or biotic factors might also be driving eusuchian palaeodiversity dynamics.

First fossil of the Giant Armored Catfish Acanthicus (Siluriformes, Loricariidae) from the Late Miocene of Entre Ríos Province, Argentina

Zootaxa ◽  
2020 ◽  
Vol 4808 (3) ◽  
pp. 571-581
Author(s):  
SERGIO BOGAN ◽  
FEDERICO L. AGNOLIN
Keyword(s):  
South America ◽  
Late Miocene ◽  
Large River ◽  
River Channels ◽  
Present Contribution ◽  
Neotropical Fishes ◽  
Northern Half ◽  
Late Neogene ◽  
Single Genus ◽  
Entre Rios

Loricariidae is a very diverse lineage of Neotropical fishes, being the most speciose family of the order Siluriformes. However, the loricariid fossil record is still very sparse. The aim of the present contribution is to describe in detail several bones belonging to the loricariid genus Acanthicus coming from late Miocene beds located at the Paraná River cliffs, Entre Ríos province, Argentina. Fishes of the Acanthicus clade are currently restricted to the northern half of South America, being mainly distributed in the Orinoco and Amazonas basins, with a single genus reaching the Paraná-Plata basin. Acanthicus adds to the list of several taxa that are shared by the Miocene of Paraná, Amazonas and Orinoco basins, but that nowadays are absent in the former (e.g., Colossoma, Phractocephalus, and Brachyplatystoma), and are typical of large river channels. This report of Acanthicus supports a close affinity between freshwater faunas of the Paraná, Orinoco, and Amazonas basins. Miocene fossils of freshwater fishes recorded in Paraná beds shed light on the connections between ancient basins of South America and also indicate that several fish clades suffered regional extinctions during the late Neogene or the beginning of the Quaternary. 

scholarly journals A new enigmatic Late Miocene mylodontoid sloth from northern South America

2015 ◽  
Vol 2 (4) ◽  
pp. 150138 ◽  
Author(s):  
Ascanio D. Rincón ◽  
H. Gregory McDonald ◽  
Andrés Solórzano ◽  
Mónica Núñez Flores ◽  
Damián Ruiz-Ramoni
Keyword(s):  
South America ◽  
Late Miocene ◽  
Northern South America

A new species ofScirrotheriumEdmund & Theodor, 1997 (Xenarthra, Cingulata, Pampatheriidae) from the late Miocene of South America

2013 ◽  
Vol 37 (2) ◽  
pp. 177-188 ◽  
Author(s):  
Flávio Góis ◽  
Gustavo Juan Scillato-Yané ◽  
Alfredo Armando Carlini ◽  
Edson Guilherme
Keyword(s):  
New Species ◽  
South America ◽  
Late Miocene ◽  
A New Species

New Late Miocene Dromomerycine Artiodactyl from the Amazon Basin: Implications for Interchange Dynamics

2014 ◽  
Vol 88 (3) ◽  
pp. 434-443 ◽  
Author(s):  
Donald R. Prothero ◽  
Kenneth E. Campbell ◽  
Brian L. Beatty ◽  
Carl D. Frailey
Keyword(s):  
North America ◽  
South America ◽  
Late Miocene ◽  
Amazon Basin ◽  
New Taxon ◽  
Isthmus Of Panama ◽  
Great American Biotic Interchange ◽  
American Immigrant ◽  
Early Late ◽  
Ground Sloths

A new dromomerycine palaeomerycid artiodactyl, Surameryx acrensis new genus new species, from upper Miocene deposits of the Amazon Basin documents the first and only known occurrence of this Northern Hemisphere group in South America. Osteological characters place the new taxon among the earliest known dromomerycine artiodactyls, most similar to Barbouromeryx trigonocorneus, which lived in North America during the early to middle Miocene, 20–16 Ma. Although it has long been assumed that the Great American Biotic Interchange (GABI) began with the closure of the Isthmus of Panama in the late Pliocene, or ca. 3.0–2.5 Ma, the presence of this North American immigrant in Amazonia is further evidence that terrestrial connections between North America and South America through Panama existed as early as the early late Miocene, or ca. 9.5 Ma. This early interchange date was previously indicated by approximately coeval specimens of proboscideans, peccaries, and tapirs in South America and ground sloths in North America. Although palaeomerycids apparently never flourished in South America, proboscideans thrived there until the end of the Pleistocene, and peccaries and tapirs diversified and still live there today.

scholarly journals A new enigmatic Late Miocene mylodontoid sloth from northern South America

2015 ◽  
Vol 2 (2) ◽  
pp. 140256 ◽  
Author(s):  
Ascanio D. Rincón ◽  
H. Gregory McDonald ◽  
Andrés Solórzano ◽  
Mónica Núñez Flores ◽  
Damián Ruiz-Ramoni
Keyword(s):  
South America ◽  
Late Miocene ◽  
Preliminary Analysis ◽  
New Genus ◽  
New Taxon ◽  
New Genus And Species ◽  
Consensus Tree ◽  
Discriminate Analysis ◽  
Northern South America ◽  
Phylogenetic Affinities

A new genus and species of sloth ( Eionaletherium tanycnemius gen. et sp. nov.) recently collected from the Late Miocene Urumaco Formation, Venezuela (northern South America) is herein described based on a partial skeleton including associated femora and tibiae. In order to make a preliminary analysis of the phylogenetic affinities of this new sloth we performed a discriminate analysis based on several characters of the femur and tibia of selected Mylodontoidea and Megatherioidea sloths. The consensus tree produced indicates that the new sloth, E. tanycnemius , is a member of the Mylodontoidea. Surprisingly, the new taxon shows some enigmatic features among Neogene mylodontoid sloths, e.g. femur with a robust lesser trochanter that projects medially and the straight distinctly elongated tibia. The discovery of E. tanycnemius increases the diversity of sloths present in the Urumaco sequence to ten taxa. This taxon supports previous studies of the sloth assemblage from the Urumaco sequence as it further indicates that there are several sloth lineages present that are unknown from the better sampled areas of southern South America.

scholarly journals Diversity and biostratigraphy of the late Oligocene-late Miocene sand dollars (Echinoidea: Scutelliformes) of Argentina and Uruguay

2021 ◽  
Vol 69 (Suppl.1) ◽  
pp. 35-50
Author(s):  
Claudia-J. Del Río ◽  
Sergio Martínez
Keyword(s):  
South America ◽  
Late Miocene ◽  
Middle Miocene ◽  
Field Work ◽  
Early Miocene ◽  
Late Oligocene ◽  
Good Correspondence ◽  
Shallow Marine ◽  
Sand Dollars ◽  
Temporal Dimensions

Introduction: Scutelliforms were diverse and widespread in shallow marine environments during Neogene times in South America. Nevertheless, they have almost never been used as biostratigraphic tools. Objective: To provide a refined stratigraphic frame useful for calibrating temporal dimensions of scutelliform diversity from Argentina and Uruguay and its correlation with the molluscan assemblages previously proposed. Methods: A detailed survey of their geographic and stratigraphic provenance was carried out. We revised both the bibliography and collections (institutional and from our own field work). Results: The group is represented by 14 species belonging to six genera, and four assemblages were identified. Numerical dates of the Neogene marine rocks obtained recently allowed their placement in a chronological scheme: “Iheringiella” sp. A is restricted to the late Oligocene, the genera Camachoaster and “Eoscutella” and the species Monophoraster telfordi to the early Miocene, Abertella gualichensis and Abertella miskellyi to the middle Miocene, and Monophoraster duboisi, Amplaster coloniensis and Amplaster ellipticus to the late Miocene. Non-lunulate scutelliforms are not restricted to the late Oligocene as previously supposed. The oldest occurrence of the genus Monophoraster corresponds to the early Miocene, and along with Iheringiella are long-living taxa that embrace the 25.3 Ma-18.1 Ma (Iheringiella patagonensis) and approximately 15 Ma-6.48 Ma (Monophoraster darwini) intervals. The presence of Iheringiella in the early Miocene of northeastern Patagonia is corroborated, reaching there its northernmost distribution. Monophoraster darwini has a temporal range from the late Miocene (where it was previously thought to be restricted) back to the middle Miocene, since this is the species yielded in the well-known and discussed “Monophoraster and Venericor Beds”. Conclusions: The Paleogene-Neogene scutelliforms of Argentina and Uruguay range from the late Oligocene to the late Miocene. There is a good correspondence among the numerical ages, molluscan biozones and scutelliform assemblages.

Sign in / Sign up

Export Citation Format

Share Document