scholarly journals Pleistocene Mammals from Pampean Region (Argentina). Biostratigraphic, Biogeographic, and Environmental Implications

Quaternary ◽  
2021 ◽  
Vol 4 (2) ◽  
pp. 15
Author(s):  
José Luis Prado ◽  
María Teresa Alberdi ◽  
Jonathan Bellinzoni

The Pampean Region contains sedimentary sequences with abundant mammal fossil records, which constitute the chronological outline of the Plio–Pleistocene of South America. These classic localities have been used for more than a century to correlate with other South American regions. Throughout this time, a series of misinterpretations have appeared. To understand the stratigraphic significance of these localities and the geochronological situation of each unit referring to the Pleistocene, a critical historical study of the antecedents was carried out, evaluating the state of each unit. The biostratigraphic studies of the Pampean Region’s mammalian faunas improved the understanding of biogeographic changes taking into account the environmental fluctuations of the Pleistocene.

2016 ◽  
Vol 1 (3) ◽  
pp. 11 ◽  
Author(s):  
Sanford R. Silverburg ◽  
Angélica Johanna Alba Cuéllar

<h2>All but one of the states in South American have extended some type of diplomatic recognition to Palestine.  There is a discussion of the meaning of diplomatic recognition in the current state system with its importance. The central theme of this paper is an examination of the process and an explanation for South American states’ provision of diplomatic recognition to Palestine while one other in the same cultural-geographical region has not.</h2>


2011 ◽  
Vol 85 (1) ◽  
pp. 69-75 ◽  
Author(s):  
Leopoldo H. Soibelzon ◽  
Blaine W. Schubert

The South American giant short-faced bear (Arctotherium angustidens Gervais and Ameghino, 1880) is one of five described Arctotherium species endemic to South America and it is known for being the earliest, largest, and most carnivorous member of the genus. Here we report an extraordinarily large A. angustidens individual exhumed from Ensenadan sediments (early to middle Pleistocene) at Buenos Aires Province, Argentina. Based on overall size, degree of epiphyseal fusion, and pathologies, this bear was an old-aged male that sustained serious injuries during life. Body mass of the bear is estimated and compared to other ursid species based on a series of allometric equations. To our knowledge, this specimen now represents the largest bear ever recorded. In light of this discovery, we discuss the evolution of body size in Arctotherium (from large-to-small) and compare this to bears that exhibited different evolutionary trajectories. We suggest that the larger size and more carnivorous nature of A. angustidens, compared to later members of the genus, may reflect the relative lack of other large carnivores and abundance of herbivores in South America just after the Great American Biotic Interchange.


Zootaxa ◽  
2010 ◽  
Vol 2370 (1) ◽  
pp. 65 ◽  
Author(s):  
ANA CAROLINA CALIJORNE LOURENÇO ◽  
DÉLIO BAÊTA ◽  
ALINE CRISTINE LOPES DE ABREU ◽  
JOSÉ P. POMBAL JR.

Most species of the South American bufonid toads are placed in Rhinella Fitzinger, 1828 (Frost 2009). Currently, this genus contains 77 species and most of them are distributed in Central and South America (Frost 2009). According to Baldissera et al. (2004), the R. crucifer species group is composed of five species: R. abei (Baldissera, Caramaschi & Haddad, 2004), R. crucifer (Wied-Neuwied, 1821), R. henseli (A. Lutz, 1934), R. ornata (Spix, 1824), and R. pombali (Baldissera, Caramaschi & Haddad, 2004). This species group is widely distributed in northern Argentina, southeastern Brazil, and Uruguay (Baldissera et al. 2004; Frost 2009), and can be found in ponds and streams in forests and open areas (Heyer et al. 1990; Baldissera et al. 2004; Pombal & Gordo 2004; Eterovick & Barata 2006). Herein we describe the tadpole and advertisement call of Rhinella pombali, a species distributed throughout the Atlantic forest and in its transitional areas with the Cerrado in the State of Minas Gerais, southeastern Brazil (Frost 2009).


2020 ◽  
Vol 60 ◽  
pp. e20206010 ◽  
Author(s):  
Antonio Santos-Silva ◽  
Juan Pablo Botero ◽  
Francisco Eriberto de Lima Nascimento ◽  
Weliton Dias Silva

We studied 18 cerambycid beetle species native to South America. Seventeen represent new state records in Brazil. Particularly, Chlorethe scabrosa Zajciw, 1963 is newly reported for the state of Rio de Janeiro with exclusion of C. brachyptera Zajciw, 1963. The Brazilian state of the type locality of Dufauxia guaicurana Lane, 1955 is fixed. Pirangoclytus mendosus (Galileo & Martins, 1996) is synonymized with P. mniszechii (Chevrolat, 1862), and its holotype is a female. Variation on Trypanidius maculatus Monné & Delfino, 1980 is commented. New country and department records for Paraguay are also provided.


2020 ◽  
Vol 45 (2) ◽  
pp. 340-348
Author(s):  
James Lucas da Costa-Lima ◽  
Earl Celestino de Oliveira Chagas

Abstract—A synopsis of Dicliptera (Acanthaceae) for Brazil is presented. Six species are recognized: Dicliptera ciliaris, D. sexangularis, and D. squarrosa, widely distributed in South America; D. purpurascens, which ranges from the North Region of Brazil (in the state of Acre) to eastern Bolivia; D. gracilirama, a new species from the Atlantic Forest of northeastern Brazil; and D. granchaquenha, a new species recorded in dry and semideciduous forests in Bolivia and western Brazil, in the state of Mato Grosso do Sul. Furthermore, we propose new synonyms and designate lectotypes for eleven names. An identification key to the six accepted Dicliptera species in Brazil is provided.


Viruses ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 888
Author(s):  
Cecilia Olguin-Perglione ◽  
María Edith Barrandeguy

Equine influenza virus (EIV) is one of the most important respiratory pathogens of horses as outbreaks of the disease lead to significant economic losses worldwide. In this review, we summarize the information available on equine influenza (EI) in South America. In the region, the major events of EI occurred almost in the same period in the different countries, and the EIV isolated showed high genetic identity at the hemagglutinin gene level. It is highly likely that the continuous movement of horses, some of them subclinically infected, among South American countries, facilitated the spread of the virus. Although EI vaccination is mandatory for mobile or congregates equine populations in the region, EI outbreaks continuously threaten the equine industry. Vaccine breakdown could be related to the fact that many of the commercial vaccines available in the region contain out-of-date EIV strains, and some of them even lack reliable information about immunogenicity and efficacy. This review highlights the importance of disease surveillance and reinforces the need to harmonize quarantine and biosecurity protocols, and encourage vaccine manufacturer companies to carry out quality control procedures and update the EIV strains in their products.


Author(s):  
Mariela C. Castro ◽  
Murilo J. Dahur ◽  
Gabriel S. Ferreira

AbstractDidelphidae is the largest New World radiation of marsupials, and is mostly represented by arboreal, small- to medium-sized taxa that inhabit tropical and/or subtropical forests. The group originated and remained isolated in South America for millions of years, until the formation of the Isthmus of Panama. In this study, we present the first reconstruction of the biogeographic history of Didelphidae including all major clades, based on parametric models and stratified analyses over time. We also compiled all the pre-Quaternary fossil records of the group, and contrasted these data to our biogeographic inferences, as well as to major environmental events that occurred in the South American Cenozoic. Our results indicate the relevance of Amazonia in the early diversification of Didelphidae, including the divergence of the major clades traditionally ranked as subfamilies and tribes. Cladogeneses in other areas started in the late Miocene, an interval of intense shifts, especially in the northern portion of Andes and Amazon Basin. Occupation of other areas continued through the Pliocene, but few were only colonized in Quaternary times. The comparison between the biogeographic inference and the fossil records highlights some further steps towards better understanding the spatiotemporal evolution of the clade. Finally, our results stress that the early history of didelphids is obscured by the lack of Paleogene fossils, which are still to be unearthed from low-latitude deposits of South America.


2018 ◽  
Vol 36 (3) ◽  
pp. 937-943 ◽  
Author(s):  
Maurício J. A. Bolzan ◽  
Clezio M. Denardini ◽  
Alexandre Tardelli

Abstract. The geomagnetic field in the Brazilian sector is influenced by the South American Magnetic Anomaly (SAMA) that causes a decrease in the magnitude of the local geomagnetic field when compared to other regions in the world. Thus, the magnetometer network and data set of space weather over Brazil led by Embrace are important tools for promoting the understanding of geomagnetic fields over Brazil. In this sense, in this work we used the H component of geomagnetic fields obtained at different sites in South America in order to compare results from the phase coherence obtained from wavelet transform (WT). Results from comparison between Cachoeira Paulista (CXP) and Eusébio (EUS), and Cachoeira Paulista and São Luis (SLZ), indicated that there exist some phenomena that occur simultaneously in both locations, putting them in the same phase coherence. However, there are other phenomena putting both locations in a strong phase difference as observed between CXP and Rio Grande, Argentina (RGA). This study was done for a specific moderate geomagnetic storm that occurred in March 2003. The results are explained in terms of nonlinear interaction between physical phenomena acting in distinct geographic locations and at different times and scales. Keywords. Geomagnetism and paleomagnetism (time variations – diurnal to secular)


2001 ◽  
Vol 33 (3) ◽  
pp. 599-609 ◽  
Author(s):  
GUILLERMO O'DONNELL

The occasion of honouring the memory of John Brooks, a great friend of Latin America, has helped me vanquish my initial reluctance to tackle a topic that is as broad, varied and still open-ended as the present situation of democracy in South America. As a first measure of my limitations, with the exception of some references to Costa Rica and Mexico, I will not discuss Central America and the Caribbean, not because I feel these regions are unimportant but because, simply, I do not know enough about them. However, when I feel that I am on sufficiently solid ground so as to refer to Latin America as a whole, I will do so.I begin by noting that in contemporary South America some countries satisfy the definition of political democracy. Those countries share two main characteristics. One is that they hold elections under universal adult franchise that, at least at the national level, are reasonably fair and competitive. These are standard criteria in the political science literature. However, having in mind the experience of Latin America and elsewhere in the third world, I believe that we should add that such elections must be institutionalised. By this I mean that all relevant actors expect that elections of this kind will continue being held in the indefinite future so, whether they like or not, it is rational for them to play democracy, not coup-making or insurrection. We should also stipulate that these elections are decisive, in the sense that those who are elected do occupy the respective offices and end their terms in the constitutionally prescribed way; they are not, as it has happened too often in Latin America, prevented from occupying office or thrown out of it because some supra-constitutional power feels that they are the ‘wrong people’.The second characteristic is the enjoyment of certain political rights, especially of opinion, expression, association, movement and access to a reasonably free and pluralist media. Of course, these and other rights are important per se; in addition, they are instrumental – necessary conditions – for the effectuation of the kind of elections I have just specified.


Oryx ◽  
2014 ◽  
Vol 49 (1) ◽  
pp. 60-63 ◽  
Author(s):  
Guilherme Braga Ferreira ◽  
Marcelo Juliano Rabelo Oliveira ◽  
Rogério Cunha de Paula ◽  
Flávio Henrique Guimarães Rodrigues ◽  
Érica Daniele Cunha Carmo

AbstractThe bush dog Speothos venaticus, a rare Near Threatened South American canid that lives in packs, was thought to be extinct in Minas Gerais state, south-eastern Brazil, until recently. Here, we report four recent records of the species in Minas Gerais, the first in the state since the description of the species in 1842. All records are from the Cerrado ecosystem in the north and north-west of the state; two are from animals found dead, one from footprints and another from a camera trap. Three of the records were inside or close (< 10 km) to strict protected areas, in a region recognized as the Protected Areas Mosaic Sertão Veredas–Peruaçu, where we expect any new records of the bush dog to be found. We discuss the low probability of detecting the bush dog and the main regional threats to the species, and emphasize the need to protect large and interconnected natural areas and keep them free of domestic dogs to avoid the extinction of the bush dog in Minas Gerais.


Sign in / Sign up

Export Citation Format

Share Document