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Potential distribution of Glossotherium robustum for (A) LIG, (B) LGM and (C) HCO, Lestodon armatus for (D) LIG, (E) LGM and (F) HCO and Mylodon darwinii for (G) LIG, (H) LGM and (I) HCO. Light green points represent records used for training while dark blue points represent records not related to the LGM or lack of precise stratigraphic control. (For interpretation of the references to color in this fi gure legend, the reader is referred to the web version of this article.)
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Species distribution models (SDMs) for the last interglacial (LIG), the global last glacial maximum (LGM) and the Holocene climatic optimum (HCO) were generated for three extinct South American Pleistocene mylodontid giant sloths, Glossotherium robustum, Lestodon armatus and Mylodon darwinii. They are recorded co-occurring in some localities includ...
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... used in isolation were "Precipitation of Wettest Month", "Minimum Temperature of Coldest Month", "Mean Temperature of Wettest Quarter" and "Precipitation of Driest Month" (Table 2). While "Precipitation of Wettest Month" was the variable that decreases the gain the most when omitted ( Table 2). The predicted potential distribution during the LGM (Fig. 2B) displayed a wide distribution for the species in South America. Areas of high probability were obtained for the Chaco-Paraná Basin and the Pampas, some zones in the Pacific coast of Chile, Peru and Ecuador, the Caribbean coasts of Colombia and Venezuela, and the northeastern intertropical region of Brazil. In all cases, high ...
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... model projection for the LIG ( Fig. 2A) also showed high proba- bility areas for the Chaco-Paraná Basin and the Pampas, an increase of suitable areas in the Brazil's intertropical region and a decrease in the Pacific and Caribbean coasts sites during the LGM. Also, the HCO projec- tion (Fig. 2C) showed similar results to LIG, but with increased suitabil- ity in tropical ...
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... model projection for the LIG ( Fig. 2A) also showed high proba- bility areas for the Chaco-Paraná Basin and the Pampas, an increase of suitable areas in the Brazil's intertropical region and a decrease in the Pacific and Caribbean coasts sites during the LGM. Also, the HCO projec- tion (Fig. 2C) showed similar results to LIG, but with increased suitabil- ity in tropical regions, particularly in the Amazon basin. Table 2). While "Precipitation of Wettest Month" decreased the gain the most when omitted ( Table ...
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... LGM predicted potential areas (Fig. 2E) showed a limited distri- bution restricted principally to the Chaco-Paraná Basin and the Pampas. Again, high probability zones are seen on exposed areas of the continental ...
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... results in the Chaco-Paraná Basin and the Pampas were ob- tained for the LIG projection (Fig. 2D), although a decrease in extremely high probability areas was also apparent. Moreover, there was a high probability area in Patagonia. The projection for HCO (Fig. 2F) showed comparable results to the LGM and LIG models, and a slight increase in potential suitable areas in the Brazil intertropical region, the Caribbean coast sites and ...
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... results in the Chaco-Paraná Basin and the Pampas were ob- tained for the LIG projection (Fig. 2D), although a decrease in extremely high probability areas was also apparent. Moreover, there was a high probability area in Patagonia. The projection for HCO (Fig. 2F) showed comparable results to the LGM and LIG models, and a slight increase in potential suitable areas in the Brazil intertropical region, the Caribbean coast sites and the Amazon basin. and "Mean Temperature of Driest Quarter" showed the highest gain when used in isolation, while "Precipitation of Wettest Month" was the variable that ...
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... predicted suitable areas for LGM (Fig. 2H) indicated a high prob- ability of occurrence of this species in Patagonia and Tierra del Fuego, which has its limit in the northern part of the Pampas. An extension of its distribution to the north is apparent for northern Chile and along the Pacific coast of Peru and Ecuador, along with a region in the Andes that forms a passage ...
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... model projection for the LIG (Fig. 2G) displayed more concen- trated areas in the southern part of the continent, although there was not noticeable change along the Pacific coasts. The HCO projection (Fig. 2I) showed a slight increase in suitability for the Pacific coasts and the Brazilian Intertropical ...
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... model projection for the LIG (Fig. 2G) displayed more concen- trated areas in the southern part of the continent, although there was not noticeable change along the Pacific coasts. The HCO projection (Fig. 2I) showed a slight increase in suitability for the Pacific coasts and the Brazilian Intertropical ...
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... of potentially suit- able areas for Glossotherium, Lestodon and Mylodon, respectively, proba- bly representing a role in the increase of the extinction risk ( Cardillo et al., 2005). However, it is noteworthy that model predictions for the LIG show similar, if not more suitable, patterns to those predicted in the HCO for all the three species ( Fig. 2; Table 3). This suggests that climatic change was not the only cause for increased risk of the extinction, leaving other causes, mainly human impact, as possible fac- tors in the demise of these and other large mammals at the end of the Pleistocene ( Sandom et al., ...
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A study of the position of the coastline was performed from the recent past (50 years) to Holocene ages (about 5000 years ago) in La Pedrera-Cabo Polonio coastal sector, in the southeast of Uruguay. Some persistent geoforms, such as marshes, located at very low elevations present lowest displacement of the recent coastline. Other recent landscapes,...
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... However, the examination of vegetation characteristics to address these possible relationships between plants and extinct megafauna has not yet been systematically investigated in the central region of Argentina, which includes the phytogeographic provinces of Espinal, Monte, and Chaco ( Figure 1). Particularly, these provinces comprise part of the core dispersal area of extinct megafauna (Prates and Perez, 2021;Varela and Fariña, 2016), and are ecologically similar to where the largest number of plant species with anachronistic traits was found (i.e. Pantanal area; Donatti et al., 2007;Guimarães et al., 2008). ...
... Pleistocene megafauna). In the first place, this vegetation overlaps with the core dispersion of extinct megafauna (Prates and Perez, 2021;Varela and Fariña, 2016). In this regard, the reconstructed distribution of megafauna species during the Pleistocene using species distribution models underscores the open and closed vegetation mosaics in which most of these species lived (Fariña et al., 2013). ...
In this paper we study the relationships between plants and extinct megafauna by examining the characteristics of the vegetation in the central region of Argentina (i.e. Espinal, Monte, and Chaco phytogeographic regions). First, we study the size, shape, quantity, and characteristics of fruits and seeds. We also evaluate the presence of mechanical (spinescence and wood density) and chemical (secondary metabolic compounds) defenses against high rates of herbivory. Complementarily, we assess the importance these plants had for human populations, using archeological, ethnographic, and current data. A high percentage of the analyzed plants met the criteria proposed for fruits and seeds dispersed by megafauna, together with a high frequency of spinescence, high density woods, and secondary metabolites. We propose that these traits cannot be explained by the herbivory pressure of extant fauna in the area, but rather developed in interaction with currently extinct fauna. We suggest that Pleistocene megafaunal extinction had important consequences in the region due to their role as ecosystem engineers and to vegetation’s characteristics, which were probably strongly shaped by megafauna activities. Among these consequences, we discuss the loss of certain interactions between these animals and vegetation, such as loss of seed dispersal mechanisms, shrub invasion, and increased susceptibility of vegetation to fire. Other effects for hunter-gatherer groups were the generation of highly regulated mobility patterns and the formation of barriers for the dispersal of prey. Finally, we also discuss the importance of these plants for human populations as food, construction material, medicines and firewood. Likewise, the role of humans as “heirs” of the megafauna in the propagation of tree and shrub species is highlighted.
... On the other hand, some Mylodontoidea are considered clear examples o digging adaptations within sloths, with several taxa showing morphological characters related to digging capacity (Pujos et al., 2012;Patiño et al., 2021). In act, several Late Pleistocene taxa have been proposed as the makers o giant ossil burrows ound in Argentina and Brazil, with the Scelidotheriidae Scelidotherium leptocephalum and the Mylodontidae Glossotherium robustum and Lestodon armatus, which are commonly ound in Uruguay (Varela and Fariña, 2016), as the most probable species responsible or these extensive galleries (Vizcaíno et al., 2001;Frank et al., 2015). Furthermore, recently discovered large ossil burrows in the Late Miocene o Central Argentina have been attributed to the scelidotheriid Proscelidodon sp. ...
We report fossil mammal burrows from backshore beach facies in the Camacho Formation of southern Uruguay, of Late Miocene (Huayquerian SALMA) age. The presence of desiccation cracks and rhizoliths indicate the occurrence of relatively extended periods of subaerial exposure and the incipient development of vegetation. The analysis of the burrow's spatial extent, size, and structure reveals the existence of exceptionally well-preserved and intercrossing tunnel systems. We show the existence of different size classes of burrows, which indicate that at least four different taxa were responsible for their construction. Considering the inferred body masses of the trace makers obtained from allometric relationships and the body masses of taxa recovered for the Camacho Formation, the burrows may have been produced by a combination of the following mammals: one of several rodents, notoungulates, cingulates, folivorans, and a carnivoran. The fossil association represents an exceptional case of a community of ecosystem engineers in the Late Miocene of southeastern South America.
... In this line, Pires et al. (2015) showed how megafauna interaction networks became more vulnerable after the arrival of modern humans to the continent, while Segura et al. (2016) found that the structure of the Pleistocene food webs was similar to modern faunas despite the exceptional body sizes of many taxa. Also, Varela and Fariña (2016) and Varela et al. (2018) studied the potential distributions of many giant xenarthrans and explored the potential co-occurrence of these taxa in South America, showing that many taxa probably exploited different resources when inhabiting the same regions. Several other studies have focused on the dietary habits of different species in order to better understand their probable roles in their ecosystems. ...
... During the last decade, several excavations have allowed the extraction of more than 2000 fossil specimens, including several typical late Pleistocene Pampean taxa, namely Lestodon armatus, Glossotherium robustum, Mylodon darwinii, Nothrotheriops sp., Glyptodon reticulatus, Doedicurus clavicaudatus, Panochthus tuberculatus, Toxodon platensis, Notiomastodon platensis, Equus neogeus, Hippidion principale, Smilodon populator, and indeterminate Cervidae and Camelidae remains (Fariña et al., 2014a;Lobato et al., 2021;Varela et al., 2023a). Interestingly, the site represents one of the relatively scarce records of several sloth taxa co-occurring, with at least five genera having been recorded (Varela and Fariña, 2016), as well as the presence of three glyptodont genera and two equids, making it extremely interesting for the study of potential differences among closely related fossil taxa. ...
... Remarkably, while Mylodon darwinii is also recorded in more southern regions (Varela and Fariña, 2016), it is important to mention that the river water δ 18 O values predicted for the Argentine Monte and Patagonian steppe are considerably positive, despite the cold environment and probably due to the dry conditions (Nan et al., 2019). Further, taxa like Hippidion principale and the indeterminate cervid showed more negative values (~6-9‰), probably indicating affinities to more humid and closed environments. ...
The analysis of stable isotopes on fossil mammals has become a widely used tool for understanding the paleoecology and paleodiet of these organisms. In this work, we study the stable isotope composition of collagen (δ13C and δ15N) and bioapatite (δ13C and δ18O) of fossil bones from Arroyo del Vizcaíno, a fossiliferous site in southern Uruguay dated to ∼32 ka cal BP. Fourteen taxa were analyzed: the ground sloths Lestodon armatus, Glossotherium robustum, Mylodon darwinii, Valgipes bucklandi and Nothrotheriops sp.; the glyptodonts Glyptodon reticulatus, Panochthus tuberculatus, and Doedicurus clavicaudatus; the equids Hippidion principale and Equus neogeus; the proboscidean Notiomastodon platensis; the notoungulate Toxodon platensis; the saber-tooth felid Smilodon populator; and an indeterminate cervid. In general, the percentage of nitrogen in collagen and the C:N ratio were within the limits expected for collagen preservation in fossil bone. The δ13C and δ15N results of the herbivores indicated that most taxa consumed high proportions of C3 plants in open, relatively dry environments, but significant variations were observed. Furthermore, relatively high values of δ18O in bone bioapatite, which approximately tracks local drinking water, indicated low precipitation and/or high evaporation. Our results show that the herbivorous taxa present at the site covered a considerable range of the grazer-browser spectrum and support the existence of niche partitioning among closely related taxa. Overall, these kinds of approaches are indispensable to better understand how these communities thrived during the Pleistocene in the region, supporting an outstanding number of giant species, before their extinction at the Pleistocene-Holocene transition.
... Glyptodont diversity has been overestimated for the Pleistocene, and following several taxonomic revisions, some authors now suggest a decline in the Pleistocene glyptodont diversity probably due to several causes, related to the increase in body size, different latitudinal distribution of the genera, or the drastic climatic changes during this period (Cuadrelli et al., 2019Vizcaíno et al., 2012;Zurita et al., 2016Zurita et al., , 2018. The Pampean Region marks the ecoregion between the tropical and the temperate/arid ecosystems associated with a high productivity related to the Paleo-Parana River floods (Varela & Fariña, 2016;Varela et al., 2018), a region inhabited by the southern glyptodont taxa. Two radiations within the glyptodont have been identified (e.g., Nuñez-Blasco et al., 2021). ...
With their odd cranial features, glyptodonts, closely related to extant armadillos, are a highly diverse group of the South American megafauna. Doedicurus, Glyptodon, Panochthus, and Neosclerocalyptus were present in the “Pampean Formation” during the Pleistocene, and they are all exceptionally preserved in the Santiago Roth Collection, thus ofering the possibility of investigating these four well-diversifed genera. A total of 13 specimens (seven species) were analysed and compared in a qualitative/quantitative study of external cranial remains and endocranial reconstructions (i.e., braincase and associated cranial canals, and inner ears). We report on anatomical features that contribute to existing phylogenetic matrices; many of them are new potential synapomorphies supporting the current hypotheses regarding the evolutionary history of the Pleistocene glyptodonts. These include the anterior cranial shape, the position of the basicranium in respect to the whole cranium, the shape of the cranial roof, the position of the largest semicircular canal, and the inclination of the cerebrum. They may represent new shared-derived features among Glyptodon, Doedicurus, Neosclerocalyptus, and Panochthus. We also provide detailed comparative descriptions highlighting new potential convergences in respect to current phylogenies, concerning, for instance, the shape of the foramen magnum, the global shape of the cranium, orbital shape, cochlear position, and a strong protrusion of the zygomatic process of the squamosal. In light of these results, we discuss morphological transformations across phylogeny. The endocranial comparison brought insights on the phylogenetic patterns of cranial canal evolution.
... The scanned specimens represent mandibles of adult individuals of representatives of one of the mayor clades of sloths, the Mylodontoidea (Delsuc et al. 2019; Varela et al. 2019), namely Lestodon armatus, Glossotherium robustum, Mylodon darwinii, Scelidotherium leptocephalum, and Valgipes bucklandi. The specimens also correspond the some of the most representative taxa of the Río de la Plata region during the Late Pleistocene (Varela and Fariña 2016;Varela et a. 2018). The models were used in Varela et al. (2023) to perform Finite Elements Analysis and Geometric Morphometrics to explore potential differences among taxa regarding their dietary specializations. ...
The present 3D Dataset contains the 3D models analyzed in 3D Finite Element Analysis and Geometric Morphometrics of Sloths (Xenarthra, Folivora) Mandibles Show Insights on the Dietary Specializations of Fossil Taxa. Journal of South American Earth Sciences. doi: https://doi.org/10.1016/j.jsames.2023.104445.
... Moreover, different dietary preferences have been predicted for the included taxa, namely semi-arboreal browsers, open-habitat browsers, and grazers (Bargo and Vizcaíno, 2008;Pujos et al., 2012). Also, several of the studied taxa inhabited similar environments and some of them are recorded as co-occurring at some sites, showing that these taxa probably competed for resources or specialized in different food types (McDonald et al., 2013;Varela and Fariña, 2016;Varela et al., 2018;McDonald, 2021). ...
... This particularity could indicate different feeding habits for this taxon compared to those predicted for the other studied scelidotheriid, S. leptocephalum, diverging from the specialist, selective/browser habits predicted for most members of the family (Miño-Boilini, 2012) and including more varied foods. Nevertheless, the obtained differentiation among mylodontoids is interesting, since these taxa have been found co-occurring at some sites and their potential distributions widely overlap at the Río de la Plata region, indicating that a certain niche differentiation could exist among these taxa (Varela and Fariña, 2016;Varela et al., 2018). For example, at least five sloth genera have been recorded at the Arroyo del Vizcaíno site in southern Uruguay, namely Lestodon armatus, Glossotherium robustum, Mylodon darwinii, Valgipes bucklandi, and Nothrotheriops sp., and different evidence points to the existence of different dietary habits among these taxa (Fariña et al., 2014;Varela and Fariña, 2016;Lobato et al., 2021;. ...
... Nevertheless, the obtained differentiation among mylodontoids is interesting, since these taxa have been found co-occurring at some sites and their potential distributions widely overlap at the Río de la Plata region, indicating that a certain niche differentiation could exist among these taxa (Varela and Fariña, 2016;Varela et al., 2018). For example, at least five sloth genera have been recorded at the Arroyo del Vizcaíno site in southern Uruguay, namely Lestodon armatus, Glossotherium robustum, Mylodon darwinii, Valgipes bucklandi, and Nothrotheriops sp., and different evidence points to the existence of different dietary habits among these taxa (Fariña et al., 2014;Varela and Fariña, 2016;Lobato et al., 2021;. On the other hand, Megatherium americanum showed the highest vMs and SE values among the studied taxa, indicating a mandible less efficient for the processing of hard food objects. ...
Sloths are represented today only by two distantly-related small, arboreal, and folivorous genera. However, the fossil record of the clade is composed of many more taxa, with much more diverse morphologies, including giant terrestrial forms with no clear modern analogs. In this context, several approaches have been implemented in order to explore the ecological adaptations of fossil taxa and, in particular, their dietary preferences. In this work we used 3D Finite Elements Analysis (FEA) coupled with Geometric Morphometrics (GMM) to explore the ecomorphology of sloths and possible differences among taxa related to dietary adaptations. Digital models of the mandibles of 14 taxa were obtained (two extant and twelve extinct), representing members of all the major clades within the group. We modeled the actions of the three major muscles involved in mastication (masseter, temporalis, and pterygoideus) and simulated unilateral mastication in four different conditions, one for each tooth along the toothrow. The results were analyzed qualitatively regarding the distribution of von Mises stress (vMs) and quantitatively using the mesh-weighted arithmetic mean (MWAM) vMs, strain energy (SE), and mechanical efficiency (ME). Differences in the distribution of high-vMs areas and lower SE values were found among taxa predicted to be grazers in comparison to those predicted to be browsers. Furthermore, when simulating biting with the most anterior tooth, we observed considerably higher vMs and SE values in taxa with a caniniform, which could indicate its involvement in sexual display rather than in food processing, acquisition, or other strenuous activities.
... . Geographic distribution of Mylodontidae during the Quaternary in South America according to Cartelle (1991), Esteban (1993), Cartelle et al. (2009), Brandoni et al. (2010), Silva et al. (2010), Corona et al. (2013), Miño-Boilini et al. (2014), Favotti et al. (2015), Varela & Fariña (2015) ...
Diagnoses of Mylodontidae species are generally based on skull, mandibular, and tooth characteristics, and rarely on postcranial morphology, due to the lack of postcranial material associated with the cranial material. The studies of postcranial anatomy have generally a biomechanical focus and reflect a set of functions of skeletal structures, but their interpretation in phylogenetic analysis is still limited. In Pleistocene deposits of Rio Grande do Sul State, Brazil, an important set of postcranial specimens was collected, belonging to Mylodontidae. They were morphologically and morphometrically analyzed, allowing us to observe some diagnostic characters such as the humeral entepicondylar foramen and crests, shape of the radial shaft, angle of distal articulation of the tibia, as well as the angle of proximal articulation of the astragalus. The material was also compared with specimens from other South American localities. Most of the remains were assigned to Glossotherium robustum and Lestodon armatus. In addition, a new Scelidotheriinae was recorded for Rio Grande do Sul State. The study indicated significant differences in the postcranial morphology, which allowed the recognition of some specific diagnostic characters. Keywords: Mylodontinae, Scelidotheriinae, hindlimb, forelimb, Pleistocene, Rio Grande do Sul.
... This would also indicate there was a drastic reduction in total available areas of preferred habitat for these three taxa with the rise in sea level at the end of the Pleistocene. Based on their co-occurrence at the Arroyo del Vizcaíno site, Uruguay, they were utilizing vegetation indicative of open, cold to temperate habitats but with mixed patches typical of humid climates [177]. ...
Late Pleistocene sloths were widely distributed and present in a diversity of habitats in South, Central, and North America and some Caribbean Islands. Late Pleistocene sloths include 27 genera in four families Megatheriidae, Megalonychidae, Mylodontidae, and Nothrotheriidae. There is no consensus on the number of valid species. Some sloths have wide geographic distributions and are present on multiple continents while others have a much smaller distribution. Our knowledge of the paleoecology and natural history of the different sloths varies greatly depending on their relative abundance. The wide distribution of sloths and adaptations to different habitats results in several “sloth” faunas with different taxonomic compositions. These generalized faunas can be distinguished geographically as Temperate North America (five genera), Southern Mexico and Central America (five genera), Northern South America (two genera), West Coast of South America (four genera), the Andes and Altiplano (four genera), Brazilian Intertropical Region (nine genera), Pampas-Patagonia and the Caribbean Islands (Cuba, Hispaniola, and Puerto Rico, four genera). Some genera may occur in multiple regions but are represented by different species. These regions also have differences in other mammalian taxa, so the sloths are often in ecological competition with different megaherbivores or preyed on by different carnivores.
... The specimen represents one of the scarce records of this taxon for South America and contributes to the knowledge of its distribution in the continent. Furthermore, the new record of Nothrotheriops increases to five the number of sloth taxa found at the site, where the mylodontids Lestodon armatus, Glossotherium robustum, and Mylodon darwinii and the scelidotheriid Valgipes bucklandi were previously reported (Varela and Fariña, 2016;Lobato et al. 2021). The data regarding the specimen is published in Varela et al. (2023). ...
The present 3D Dataset contains the 3D model analyzed in the following publication: occurrence of the ground sloth Nothrotheriops (Xenarthra, Folivora) in the Late Pleistocene of Uruguay: New information on its dietary and habitat preferences based on stable isotope analysis. Journal of Mammalian Evolution. https://doi.org/10.1007/s10914-023-09660-w
... Amongst these taxa, Lestodon represents the vast majority of fossils found. The co-occurrence of multiple mylodontids at AdV was discussed by Varela and Fariña (2016) and the presence of V. bucklandi was reported recently by Lobato et al. (2021), further increasing the sloth species diversity for the site and providing valuable information on the potential interactions among these taxa. Other taxa recorded for the site include: three glyptodonts, Glyptodon reticulatus, Doedicurus clavicaudatus, and Panochthus tuberculatus; the notoungulate Toxodon platensis; the proboscidean Notiomastodon platensis; the equid Hippidion sp.; as well as indeterminate Cervidae and Camelidae remains; and a single predator, the felid, Smilodon populator (Fariña et al. 2014). ...
... Finally, Oliveira et al. (2017) suggested a dry environment for the Mato Grosso do Sul specimens possibly assignable to Nothrotheriops sp. Overall, the results are compatible with the predicted environments for the northern species of Nothrotheriops, N. shastensis, and are consistent with previous results supporting the existence of complex open mosaic habitats with patches of mixed vegetation in the Río de la Plata region (Varela and Fariña 2016;Varela et al. 2018;Lobato et al. 2021). ...
... Another relevant aspect of the occurrence of Nothrotheriops sp. in the AdV site is related to the presence of other sloths recorded at the site and the potential niche partitioning between these taxa, similar to that seen in North America (McDonald 2021). As mentioned above, four sloths have been previously recognized for the site, Lestodon armatus, Glossotherium robustum, Mylodon darwinii, and Valgipes bucklandi (Fariña et al. 2014;Varela and Fariña 2016;Lobato et al. 2021). Considering the nature of the site, which is interpreted to have formed during a relatively short time span (Fariña et al. 2014), populations of these five sloths should have coexisted in southern Uruguay during the Late Pleistocene. ...
Sloths represent one of the most successful South American clades that reached North America during the Great American Biotic Interchange (GABI). At least four families are known from the Pleistocene of North America: Mylodontidae, Megalonychidae, Megatheriidae, and Nothrotheriidae. Members of the Nothrotheriidae are known from the Middle Miocene to the Pleistocene/Holocene transition in the Americas, but Nothrotheriops is the only genus in the family recorded in North America. Recently, femora with characteristic nothrothere morphology were recovered from Santa Fe, Argentina, and assigned to Nothrotheriops, thus greatly expanding the geographic distribution of this taxon. In Uruguay, records of Quaternary Nothrotheriidae are scarce, and previous reports are limited to the genus Nothrotherium. In this work, we describe a humerus from Arroyo del Vizcaíno (AdV), a ~30 ka site located in southern Uruguay, and assign it to the nothrotheriid Nothrotheriops sp. We also discuss several specimens from Uruguay originally assigned to Nothrotherium, which upon re-examination can be tentatively reassigned to Nothrotheriops sp. Furthermore, we employ stable isotope analysis to explore the climatic and dietary preferences of this taxon in South America. The new records are consistent with the materials reported from Argentina, thus providing new knowledge of the geographic distribution of the taxon, as well as its climatic and dietary preferences. Stable isotope results showed δ13C values consistent with diets based mainly on C3 plants, similar to those published for N. shastensis in North America.
