The auditory region of a fossil caviomorph rodent (Hystricognathi) from the early Miocene of Patagonia (South America) and evolutionary considerations (project)

10.7934/p3715 ◽  
2020 ◽  
Author(s):  
M Arnaudo ◽  
M Arnal ◽  
E Ekdale
Keyword(s):  
South America ◽  
Early Miocene ◽  
Auditory Region

A novel late Early Miocene assemblage of terrestrial gastropods from Santa Cruz (Patagonia, Argentina)

2015 ◽  
Vol 89 (5) ◽  
pp. 748-761 ◽  
Author(s):  
Sergio E. Miquel ◽  
Pablo E. Rodriguez
Keyword(s):  
South America ◽  
New Taxa ◽  
Vegetation Cover ◽  
First Record ◽  
Early Miocene ◽  
New Taxon ◽  
Santa Cruz ◽  
Dense Vegetation ◽  
Humid Environment ◽  
New Information

AbstractA remarkable fossil assemblage composed of five gastropod taxa is described from the Early Miocene of Santa Cruz (Patagonia, Argentina) in southernmost South America. The assemblage includes extinct and living genera South America, and on geographic distributions and represent background new information on spatial and across time distributions as well as identification of new taxa. A new taxon,Patagocharopa enigmatican. gen. n. sp., is tentatively assigned to Charopidae.Gastrocopta patagonican. sp. (Vertiginidae) represents the oldest record ofGastrocoptain Argentina and the southernmost record for the Americas.Punctum patagonicumn. sp. (Punctidae) represents the first record ofPunctumfor continental South America, and characterized by a protoconch with traces of axial costulae and a teleoconch with strong radial ribs.Zilchogyra miocenican. sp. is the first Miocene record of the charopid genusZilchogyra. Fragments of a possibleScolodonta(Scolodontidae) are recorded. Overall, the assemblage represents an important and useful paleoenvironmental tool. This fauna suggests that a more temperate and humid environment than today—with a more dense vegetation cover—was prevalent at this site during the Early Miocene.

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.

Herminespina: New genus of Neogene muricid gastropod from Peru and Chile

1997 ◽  
Vol 71 (4) ◽  
pp. 610-615 ◽  
Author(s):  
T. J. DeVries ◽  
G. J. Vermeij
Keyword(s):  
South America ◽  
Late Miocene ◽  
New Genus ◽  
Geographic Range ◽  
Early Miocene ◽  
South American ◽  
South American Species ◽  
Late Pliocene ◽  
Early Pliocene ◽  
Southern Peru

The new genus Herminespina comprises extinct South American species of “Thais”-like ocenebrine gastropods with prominent colabral folds and a labral spine. Geographic range extensions into Peru are reported for the late Pliocene H. mirabilis and the late Miocene to Pliocene H. philippii, both previously known only from Chile. A new early Pliocene species, H. saskiae, is described from the Sacaco Basin of southern Peru and compared with an early Miocene muricid from Peru and Chile, Acanthina katzi. Herminespina is one of several genera of Neogene muricids in western South America that bear labral spines.

LACUSTRINE SYSTEMS IN THE EARLY MIOCENE OF NORTHERN SOUTH AMERICA—EVIDENCE FROM THE UPPER MAGDALENA VALLEY, COLOMBIA

Palaios ◽  
2019 ◽  
Vol 34 (10) ◽  
pp. 490-505
Author(s):  
FELIPE DE LA PARRA ◽  
DIEGO PINZON ◽  
GUILLERMO RODRIGUEZ ◽  
OMAR BEDOYA ◽  
ROGER BENSON
Keyword(s):  
South America ◽  
Biological Diversity ◽  
Water Bodies ◽  
Early Miocene ◽  
Depositional Sequence ◽  
Lacustrine Deposits ◽  
Tectonic Processes ◽  
Northern South America ◽  
Intramontane Basins ◽  
Detailed Record

ABSTRACT Extensive areas covered by semi-permanent water bodies were common during the Miocene in the Neotropics. These floods are noteworthy because of their possible role in promoting the high biological diversity observed today in the Amazonia. In particular, a relatively good understanding of the floods has been achieved for the Llanos basin of Colombia and western Amazonia. In these two basins the evidence suggests episodes of marine incursions and development of lacustrine systems at different times during the Miocene. Other intra-montane basins in Colombia, like the Middle and Upper Magdalena basins, also show clear evidence that water bodies covered them during that time. However, the chronostratigraphy and paleoecology of these deposits are still unclear. In this study, we use the palynological record of the Middle and Upper Magdalena valleys to establish the age of the deposits of the Barzalosa Formation, a unit that preserves a detailed record of a lacustrine system deposited during the late early Miocene in the Upper Magdalena Valley. The results indicate that the Barzalosa Formation is correlative with the lacustrine deposits of the La Cira fossiliferous horizon in the Middle Magdalena Valley. This indicates that extensive lacustrine systems covered the intramontane basins of the northern Andes during the early Miocene. Paleoecologically, the Barzalosa Formation is the result of the evolution of a lacustrine system in three phases, which show marked differences in the proportion of algae, palynological composition and sedimentary depositional sequence. Climate and tectonic processes were the most probable mechanisms controlling the evolution of the Barzalosa system.

HUESSER HORIZON: A LAKE AND A MARINE INCURSION IN NORTHWESTERN SOUTH AMERICA DURING THE EARLY MIOCENE

Palaios ◽  
2009 ◽  
Vol 24 (4) ◽  
pp. 199-210 ◽  
Author(s):  
A. A. GOMEZ ◽  
C. A. JARAMILLO ◽  
M. PARRA ◽  
A. MORA
Keyword(s):  
South America ◽  
Early Miocene

The southernmost fossil record of Squamates

2017 ◽  
Vol 38 (1) ◽  
pp. 15-30 ◽  
Author(s):  
Adriana Albino ◽  
Santiago Brizuela ◽  
Sergio Vizcaíno
Keyword(s):  
South America ◽  
Fossil Record ◽  
Early Miocene ◽  
Substantial Part ◽  
South American ◽  
Santa Cruz ◽  
Origin And Evolution ◽  
Present Distribution ◽  
First Time

Squamates form a substantial part of the present-day South American herpetofauna, and their fossils constitute an indispensable evidence for understanding the origin and evolution of the main taxa. Squamates are relatively common in Miocene localities of Patagonia, especially in levels of the late early Miocene Santa Cruz Formation. In this contribution, remains of the three species of the extinct iguanidErichosaurusAmeghino 1899 (E. diminutus,E. bombimaxillaandE. debilis) are redescribed, and new squamate specimens are reported for first time. The genusErichosaurusis considered invalid.Erichosaurus debilis,E. diminutusand a new specimen are recognized as indeterminate species of the extant polichrotinePristidactylus, whereasE. bombimaxillaremains as an indeterminate iguanid. Snakes are represented by an indeterminate colubrid. All these specimens, together with a tupinambine teiid previously described for the same formation, represent the southernmost fossil record of squamates in South America and indicate the occurrence of the iguanidPristidactylus, the teiidTupinambisand the colubrid snakes south to their present distribution as back as during the early Miocene.

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