Taxonomy of Ctenomys (Rodentia: Ctenomyidae) in northwestern Patagonia, Argentina: the occurrence of the “mendocinus” lineage

Mammalia ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mauro N. Tammone ◽  
Ulyses F.J. Pardiñas
Keyword(s):  
South America ◽  
Molecular Data ◽  
Species Level ◽  
Subterranean Rodents ◽  
Mammalian Fauna ◽  
Southern South America ◽  
Monte Desert ◽  
Desert Shrub ◽  
Northern Patagonia ◽  
Northern Portion

Abstract Subterranean rodents Ctenomys are iconic representatives of the mammalian fauna from southern South America. Based on molecular data, eight lineages have been identified within the genus, although species-level identifications and relationships are still debated. Until now, the “magellanicus” clade has been the only lineage mentioned from arid, extra-Andean portions of Patagonia. Here, we report the presence of a Ctenomys population from northern Patagonia that is unambiguously associated with the Central Argentinean “mendocinus” lineage. Most of the 160,000 km2 comprising the northern portion of Patagonia – an area consisting primarily of Monte Desert shrub-land – are inhabited by Ctenomys populations of unknown taxonomy.

scholarly journals Patterns of bryophyte and lichen diversity in bogs and Tepualia stipularis forests of Northern Patagonia (Chile): evidence of a novel ecosystem in southern South America

2016 ◽  
Vol 94 (3) ◽  
pp. 441 ◽  
Author(s):  
Carolina A. León ◽  
Gisela Oliván-Martínez ◽  
Gisela Oliván-Martínez ◽  
Juan Larraín ◽  
Juan Larraín ◽  
...  
Keyword(s):  
South America ◽  
Novel Ecosystem ◽  
Southern South America ◽  
Northern Patagonia ◽  
Lichen Diversity

scholarly journals New molecular data on subcutaneous Philornis (Diptera: Muscidae) from southern South America suggests the existence of a species complex

2016 ◽  
Vol 87 (4) ◽  
pp. 1383-1386 ◽  
Author(s):  
Martín A. Quiroga ◽  
Lucas D. Monje ◽  
Juan P. Arrabal ◽  
Pablo M. Beldomenico
Keyword(s):  
South America ◽  
Species Complex ◽  
Molecular Data ◽  
Southern South America

scholarly journals Geographic variation in quantitative skull traits and systematic of southern populations of the leaf-eared mice of the Phyllotis xanthopygus complex (Cricetidae, Phyllotini) in southern South America

Zootaxa ◽  
2018 ◽  
Vol 4446 (1) ◽  
pp. 68
Author(s):  
PABLO TETA ◽  
J. PABLO JAYAT ◽  
CECILIA LANZONE ◽  
AGUSTINA OJEDA
Keyword(s):  
South America ◽  
Molecular Data ◽  
Valid Species ◽  
Skull Morphology ◽  
North Central ◽  
Southern South America ◽  
Central Argentina ◽  
The North ◽  
West Central ◽  
Neotropical Rodents

The leaf-eared mice of the genus Phyllotis (Cricetidae, Phyllotini) encompasses at least 20 species of medium-sized Neotropical rodents mostly distributed throughout the Andean region. Its limits and contents were reviewed by several authors, based both on morphological and molecular data. However, no integrative approaches were conducted based on large samples of individuals with a wide geographical coverage. The purposes of this paper are: (i) to evaluate species limits; and (ii) to test the congruence between molecular and quantitative morphological evidences within the Phyllotis xanthopygus complex in southern South America. Our results questioned the specific status of P. bonariensis, a geographically isolated form that was either considered as a valid species or as a synonym of P. xanthopygus. Quantitative morphological (size and shape of the skull) and molecular data linked P. bonariensis with populations from central Argentina traditionally referred as P. xanthopygus vaccarum. Individuals belonging to populations from southern Argentina and Chile (P. x. xanthopygus) were remarkably homogeneous in their skull morphology, showing a subtle to non-existent differentiation from those of north-central and west-central Argentina referred to P. x. vaccarum. We found some incongruence between groups inferred from morphological (this work) and mitochondrial DNA results of previous studies. This is the case of the north-central and west-central populations, where morphological traits do not show the strong differentiation detected by molecular characters. Our results highlight the need for integrative taxonomic studies, not only to delimitate taxonomic units but also for a better and more comprehensive understanding of population variability and differentiation. 

Morphometric study of three closely related South American species of Hordeum section Stenostachys (Poaceae)

1992 ◽  
Vol 70 (3) ◽  
pp. 496-502 ◽  
Author(s):  
Bernard R. Baum ◽  
L. Grant Bailey
Keyword(s):  
Multivariate Analysis ◽  
South America ◽  
Species Level ◽  
The Other ◽  
Morphometric Study ◽  
South American ◽  
Morphological Investigation ◽  
South American Species ◽  
Specific Level ◽  
Southern South America

This study investigates the morphologically distinguishable characteristics of Hordeum santacrucense Parodi et Nicora and Hordeum setifolium Parodi et Nicora, two recently described species from southern South America that are very similar morphologically, and Hordeum patagonicum (Hauman) Covas, also from southern South America and morphologically similar to the above two species. The three entities have not been kept at the species level by some authors. This paper provides the results of a morphological investigation as justification for their retention at the specific level. The character lemma backs pubescent in about half lower part distinguishes H. patagonicum from the other two; the character lodicules glabrous, or with one or two cilia distinguishes H. setifolium from H. santacrucense with ciliate lodicule margins. Key words: South American Hordeum, multivariate analysis, lodicules, taxonomy.

A New Early Danian Gastropod Assemblage From Northern Patagonia, Río Negro Province, Argentina

2012 ◽  
Vol 86 (6) ◽  
pp. 1002-1016 ◽  
Author(s):  
Claudia Julia del Rio
Keyword(s):  
New Species ◽  
New Zealand ◽  
South America ◽  
New Record ◽  
New Genus ◽  
Southern South America ◽  
Northern Patagonia ◽  
Rio Negro ◽  
Endemic Genera ◽  
Eleven Species

A new early Danian gastropod assemblage contained in the Roca Formation of Río Negro Province was analyzed. Eleven species are described and illustrated, the new genus Rocalaria is created, and six new species are recognized: Gyroscala daniana, Heteroterma carmeloi, Microfulgur concheyroae, Sulcobuccinum prominentum, Cidarina lenzaniyeuensis, and Rocalaria alani. The present research includes the first mention of Sulcobuccinum d'Orbigny, 1850, Priscoficus Conrad, 1866, Cavoscala Whitfield, 1892, Microfulgur Finlay and Marwick, 1937, and Cidarina Dall, 1909, for the Danian of Southern South America; the new record of Austrophaera Furque and Camacho, 1949, Fusinus Rafinesque, 1815 and Heteroterma Gabb, 1869 in northern Patagonia; and the oldest Paleogene record for the genus Gyroscala de Boury, 1887. The presence of the study assemblage in northern Patagonia indicates a more complex paleobiogeographic pattern for the area than previously thought, as shown by the record of endemic genera, cosmopolitan taxa, elements with Tethyan/ Indo-Pacific affinities, and genera related with “Wangaloan” faunas of the Paleocene of New Zealand.

Integrative taxonomy of extant maras supports the recognition of the genera Pediolagus and Dolichotis within the Dolichotinae (Rodentia, Caviidae)

2020 ◽  
Vol 101 (3) ◽  
pp. 817-834
Author(s):  
Denise H Campo ◽  
Diego A Caraballo ◽  
Guillermo H Cassini ◽  
Sergio O Lucero ◽  
Pablo Teta
Keyword(s):  
South America ◽  
Quantitative Assessment ◽  
Molecular Data ◽  
Integrative Taxonomy ◽  
Divergence Times ◽  
Southern South America ◽  
Qualitative And Quantitative ◽  
Living Species ◽  
Morphological Differences

Abstract The subfamily Dolichotinae (Rodentia, Caviidae) includes two living species (Dolichotis patagonum and D. salinicola) of cursorial, long-legged rodents that inhabit semiarid thorn scrubs and shrublands in southern South America. Some authors consider that the morphological differences between D. patagonum and D. salinicola warrant circumscription of the latter in its own genus, Pediolagus. Based on a phylogeny and divergence times grounded on molecular data, as well as a qualitative and quantitative assessment of morphological differences, the distinction between Dolichotis and Pediolagus is equal to or greater than differences seen for other intergeneric comparisons within Cavioidea. Based on these results, we argue that the taxonomic designations of Dolichotis and Pediolagus should be retained.

A review on the cytogenetics of the tribe Oryzomyini (Rodentia: Cricetidae: Sigmodontinae), with the description of new karyotypes

Zootaxa ◽  
2020 ◽  
Vol 4876 (1) ◽  
pp. 1-111
Author(s):  
CAMILA DO NASCIMENTO MOREIRA ◽  
KAREN VENTURA ◽  
ALEXANDRE REIS PERCEQUILLO ◽  
YATIYO YONENAGA-YASSUDA
Keyword(s):  
South America ◽  
Diploid Number ◽  
Sex Chromosome ◽  
Field Work ◽  
Morphological Characters ◽  
Molecular Data ◽  
Southern South America ◽  
Karyotype Variability ◽  
Cytogenetic Studies ◽  
New Evidence

Oryzomyini represents the most diverse and speciose tribe of subfamily Sigmodontinae, with 29 genera and about 141 species. This great diversity of species is distributed from southeastern North to southern South America. Its systematics have passed through major changes in the last years due to the integration of molecular data with morphological characters in phylogenetic inferences. Unsurprisingly, cytogenetic studies on Oryzomyini reflect such diversity, with chromosome diploid number varying from 2n = 16 to 2n = 88. In addition, some species present autosomal and sex chromosome polymorphisms, besides the presence of B chromosomes. However, despite decades of cytogenetic studies, our knowledge about the karyotype variability in this group were still poorly known. Considering such deep and profound changes on the tribe, along with important new evidence that was continuously being produced associated to field work in several areas of Brazil and South America, we performed a cytogenetic review of the Oryzomyini group. We provide standardized descriptions summarizing all the knowledge associated to the known species of the tribe. We also describe seven new karyotypes for the tribe, Euryoryzomys sp., 2n = 58 and FN = 92; Neacomys sp. 1, 2n = 48 and FN = 54; Neacomys sp. 2, 2n = 54 and FN = 62; Oecomys sp. 1, 2n = 54 and FN = 84; Oecomys sp. 2, 2n = 64 and FN = 92; Oecomys sp. 3, 2n = 84 and FN = 110; and Scolomys sp., 2n = 62 and FN = 80. 

scholarly journals Amazonia as the Origin and Diversification Area of Didelphidae (Mammalia: Metatheria), and a Review of the Fossil Record of the Clade

2021 ◽  
Author(s):  
Mariela C. Castro ◽  
Murilo J. Dahur ◽  
Gabriel S. Ferreira
Keyword(s):  
South America ◽  
Amazon Basin ◽  
Parametric Models ◽  
Isthmus Of Panama ◽  
Biogeographic History ◽  
Early Diversification ◽  
Northern Portion ◽  
History Of ◽  
Environmental Events ◽  
Fossil Records

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.

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