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Nomenclature ( A , B , C ) and measurements ( D , E , F ) of Cardiatherium chasicoense teeth. A and D , right p4; B and E , right m1 or m2; C and F , right M1 or M2. Abbreviations : c.1e.–c.3e. , 1 st – 3 rd external column; c.1i.–c.3i. , 1 st – 3 rd internal column; h.1e.–h.3e. , 1 st – 3 rd external flexid;
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According to our previous model for interpreting the fossil record of capybaras the cheek teeth grow in width and length throughout life; flexids (especially h.s.i. and h.t.i.) deepen allometrically resulting in diverse occlusal morphologies during ontogeny; in the more derived species the ‘onset’ of flexid development is pre-displaced, and the rel...
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Context 1
... Spanish names in order to conform to previous publications on the Hydrochoeridae (e.g., Frailey, 1986). Linear measurements of p4 – m3 were taken with a stereomi- croscope with micrometer eyepiece and included: AP, anteroposterior length; AWa, width of prism Ia; AWb, width of prism Ib; HFEL, length of fundamental external flexid (h.f.e.); HPEL, length of primary external flexid (h.p.e.); HSEL, length of secondary external flexid (h.s.e.); HSIL, length of secondary internal flexid (h.s.i.); HTIL, length of tertiary internal flexid (h.t.i.); MW, middle width; and PW, posterior width ( Fig. 2D – F). The lengths of the flexids with respect to the tooth width were measured linearly on the occlusal surface and expressed as a percent of total tooth width. It is described in the text as the ‘ depth ’ of the flexid. Short flexids are ’ shallow ’ and long flexids are ‘ deep. ’ Only m1 and m2 were considered for the quantitative analysis because they vary less among individuals than p4 and because they are the best represented cheek teeth in the sample of Cardiatherium patagonicum on which the proposal of our model was originally based. Isolated m1s and m2s are difficult to differen- tiate; consequently, they were analyzed together. The linear measurements of m1 and m2 (Fig. 2) were log- transformed and examined through principal components analysis (PCA) based on a correlation matrix (Bookstein et al., 1985; Legendre and Legendre, 1998). AP was used as a size estimate following Vucetich et al. (2005). In order to test whether C . chasicoense follows the proposed model of growth pattern of h.t.i. and h.s.i., HSIL and HTIL versus AP of m1 – m2 (Fig. 2) were compared with allometric change of these flexids of the Huayquerian species of the genus analyzed by Vucetich and colleagues (2005). GEOLOGICAL SETTING All the remains of Chasicoan capybaras were recovered from the Las Barrancas Member of the Arroyo Chasic ó Formation (see below), in southwest Buenos Aires Province, in front of the Bajada de los Toros locality (Fig. 1A – C). This locality is about 500 m downstream from the ‘ Norma Alicia ’ bridge over Arroyo Chasic ó (IGM 1:50.000 ‘ Estancia Los Cha ñ ares ’ chart N ° 3963- 10-3; 63 ° 00 Ј 00 Љ W, 38 ° 36 Ј 30 Љ S). The Arroyo Chasic ó Formation was formalized by Pascual (1961:63) based on the ‘ Chasi- coense ’ of Kraglievich (1930) in reference to the sediments cropping out along the margins of Arroyo Chasic ó . Fidalgo and Porro (in Bondesio et al., 1980; see also Fidalgo et al., 1987) ...
Context 2
... Spanish names in order to conform to previous publications on the Hydrochoeridae (e.g., Frailey, 1986). Linear measurements of p4 – m3 were taken with a stereomi- croscope with micrometer eyepiece and included: AP, anteroposterior length; AWa, width of prism Ia; AWb, width of prism Ib; HFEL, length of fundamental external flexid (h.f.e.); HPEL, length of primary external flexid (h.p.e.); HSEL, length of secondary external flexid (h.s.e.); HSIL, length of secondary internal flexid (h.s.i.); HTIL, length of tertiary internal flexid (h.t.i.); MW, middle width; and PW, posterior width ( Fig. 2D – F). The lengths of the flexids with respect to the tooth width were measured linearly on the occlusal surface and expressed as a percent of total tooth width. It is described in the text as the ‘ depth ’ of the flexid. Short flexids are ’ shallow ’ and long flexids are ‘ deep. ’ Only m1 and m2 were considered for the quantitative analysis because they vary less among individuals than p4 and because they are the best represented cheek teeth in the sample of Cardiatherium patagonicum on which the proposal of our model was originally based. Isolated m1s and m2s are difficult to differen- tiate; consequently, they were analyzed together. The linear measurements of m1 and m2 (Fig. 2) were log- transformed and examined through principal components analysis (PCA) based on a correlation matrix (Bookstein et al., 1985; Legendre and Legendre, 1998). AP was used as a size estimate following Vucetich et al. (2005). In order to test whether C . chasicoense follows the proposed model of growth pattern of h.t.i. and h.s.i., HSIL and HTIL versus AP of m1 – m2 (Fig. 2) were compared with allometric change of these flexids of the Huayquerian species of the genus analyzed by Vucetich and colleagues (2005). GEOLOGICAL SETTING All the remains of Chasicoan capybaras were recovered from the Las Barrancas Member of the Arroyo Chasic ó Formation (see below), in southwest Buenos Aires Province, in front of the Bajada de los Toros locality (Fig. 1A – C). This locality is about 500 m downstream from the ‘ Norma Alicia ’ bridge over Arroyo Chasic ó (IGM 1:50.000 ‘ Estancia Los Cha ñ ares ’ chart N ° 3963- 10-3; 63 ° 00 Ј 00 Љ W, 38 ° 36 Ј 30 Љ S). The Arroyo Chasic ó Formation was formalized by Pascual (1961:63) based on the ‘ Chasi- coense ’ of Kraglievich (1930) in reference to the sediments cropping out along the margins of Arroyo Chasic ó . Fidalgo and Porro (in Bondesio et al., 1980; see also Fidalgo et al., 1987) ...
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Citations
... The cheek teeth of AMU-CURS-744, as well as the specimen AMU-CURS-1222, were compared with other Neogene and Quaternary hydrochoerines (Vucetich et al. 2005(Vucetich et al. , 2012(Vucetich et al. , 2014(Vucetich et al. , 2015Deschamps et al. 2007;Pérez et al. 2017;Gomes et al. 2019;Cerdeño et al. 2019). Two morphological traits of the p4 let us to assign AMU-CURS-744 to the hydrochoerine ?Hydrochoeropsis wayuu, a taxon recently described from the Pliocene of Colombia (Pérez et al. 2017): (1) the h.2i and h.3i are equally deep (also shared with Hydrochoeropsis dasseni from the Pliocene of Argentina); and (2) the fifth internal flexid (h.5i) has the same wide and depth as in ?H. wayuu, differing from other known hydrochoerines (see Pérez et al. 2017: p. 115). ...
The Pliocene–Pleistocene transition in the Neotropics is poorly understood despite the major climatic changes that occurred at the onset of the Quaternary. The San Gregorio Formation, the younger unit of the Urumaco Sequence, preserves a fauna that documents this critical transition. We report stingrays, freshwater bony fishes, amphibians, crocodiles, lizards, snakes, aquatic and terrestrial turtles, and mammals. A total of 49 taxa are reported from the Vergel Member (late Pliocene) and nine taxa from the Cocuiza Member (Early Pleistocene), with 28 and 18 taxa reported for the first time in the Urumaco sequence and Venezuela, respectively. Our findings include the first fossil record of the freshwater fishes Megaleporinus, Schizodon, Amblydoras, Scorpiodoras, and the pipesnake Anilius scytale, all from Pliocene strata. The late Pliocene and Early Pleistocene ages proposed here for the Vergel and Cocuiza members, respectively, are supported by their stratigraphic position, palynology, nannoplankton, and 86Sr/88Sr dating. Mammals from the Vergel Member are associated with the first major pulse of the Great American Biotic Interchange. In contrast to the dry conditions prevailing today, the San Gregorio Formation documents mixed open grassland/forest areas surrounding permanent freshwater systems, following the isolation of the northern South American basin from western Amazonia. These findings support the hypothesis that range contraction of many taxa to their current distribution in northern South America occurred rapidly during at least the last 1.5 million years.
... Comments: the described features of CICYTTP PV-M-3-334 are present in Hydrochoerinae taxa (Mones, 1991;Vucetich et al., 2005Vucetich et al., , 2014Deschamps et al., 2007;Pérez et al., 2014;Cerdeño et al., 2019). However, the lack of labial joining of laminae differs from Cardiatherium spp. ...
... The relatively recent consensus reached by nearly all those who study fossil and extant capybaras is that the taxonomy of, particularly, North American species is in a state of confusion and in much need of revision (e.g., Mones, 1984;Mones and Ojasti, 1986;Morgan and White, 1995;Morgan, 2008;Pérez et al., 2017;Vucetich et al., 2015). An attempt to resolve these issues is currently underway and being led primarily by the Argentine paleontologists C. M. Deschamps, M. E. Pérez, and M. G. Vucetich (e.g., Deschamps et al., 2007Deschamps et al., , 2013Vucetich et al., 2015;Pérez et al., 2017, and references therein). The main reason for such confusion is that capybaras have ever-growing cheek teeth that change in size and morphology throughout life. ...
... The result, therefore, has been an interpretation of higher taxonomic diversity in the fossil record than actually exists. Fossils of different size and morphology at a single locality are now known to represent different ontogenetic stages of a single taxon, not multiple taxa (e.g., Deschamps et al., 2007;Vucetich et al., 2015). Adding to this problem is the referral of North American Pliocene species to genera that do not appear in the fossil record of South America until the Pleistocene. ...
Within this article we provide updated correlations of many of the lithostratigraphic units within the outer Coastal Plain of South Carolina to the most up-to-date marine oxygen isotope stages. We note the first viverravid from the Atlantic Coastal Plain (Didymictis proteus) and provide new information regarding the timing of certain Neotropical immigrant taxa into the southeastern USA. This includes the oldest record of Erethizon, capybara and, possibly, Allophaiomys plioceanicus in the USA. Numerous additional new taxonomic records for the state are documented.
... In such cases, improving taxonomic assignment, as well as other aspects derived from this interpretation, such as intra/ interspecific variation, ontogeny, and paleobiology, depends on the discovery of new specimens. A clear example of this premise was demonstrated by the studies conducted by Vucetich et al. (2005) and Deschamps et al. (2007). These works revised the diversity and ontogeny of capybaras from the upper Miocene strata of Argentina. ...
Neoepiblemidae (Caviomorpha) includes South American hystricognath rodents that together with
Chinchillidae and Dinomyidae compose the clade Chinchilloidea. Despite the considerable advance in knowledge of the
past decades, these extinct rodents are still poorly studied. To contribute to the taxonomy, systematics, and ontogeny of this
group, in this paper we study the cheek tooth morphology of the genus Neoepiblema Ameghino, 1889, from upper Miocene
deposits through qualitative and quantitative analyses. For this purpose, we describe the anatomical variation, perform a
quantitative analysis using linear measurements, and provide comments on the dental replacement. Based on the cheek
tooth morphology, our interpretations indicate that there are two species of Neoepiblema that can be differentiated from
each other. Neoepiblema ambrosettianus is not a valid name, and N. horridula, the first described Neoepiblema species, is
the senior synonym. Hence, N. acreensis is a valid name for the second species of the genus. In neoepiblemids, the premolar
is replaced during the early postnatal period, similar to euhypsodont dinomyids and in contrast to some other euhypsodont
caviomorphs (e.g., cavioids), which replace the premolar during the intrauterine stage. These data on dental replacement in
neoepiblemids contribute to knowledge about the ontogeny of this extinct rodent group.
... The living hydrochoerines are represented by two species that inhabit tropical South America and southern Central America -Hydrochoerus hydrochaeris Linnaeus, 1766 and Hydrochoerus isthmius Goldman, 1912. Concerning the fossil record of this clade, South American hydrochoerines have been found in upper Miocene (Deschamps et al., 2007(Deschamps et al., , 2013Vucetich et al., 2014;Pérez et al., 2016;Kerber et al., 2017), Pliocene (e.g. Vucetich et al., 2014), and Quaternary strata (Mones, 1991;Ubilla, 1996;Deschamps, 1998;Ghizzoni, Fig. 1. ...
... Remains assigned to Hydrochoerus have been reported for several localities (Paula Couto, 1950;Winge, 1887;Oliveira et al., 1985;Castilho and Simões Lopes, 2005;Salles et al., 2006;Kerber and Ribeiro, 2011;Kerber et al., 2016;Kerber, 2017). Due to the constant taxonomic changes that have occurred over the years (vide Vucetich et al., 2005(vide Vucetich et al., , 2012(vide Vucetich et al., , 2015Deschamps et al., 2007Deschamps et al., , 2013, it is notable the necessity of to increase the data on the fossils of Hydrochoerinae. Since the seminal work "Monografía de los Hydrochoeridae" by Mones (1991), considerable advance about systematics and taxonomy of the South American capybaras have been published mainly on the Neogene taxa (Vucetich et al., 2005(Vucetich et al., , 2012(Vucetich et al., , 2015Deschamps et al., 2007Deschamps et al., , 2013, while few works have focused on the Quaternary forms. ...
... Due to the constant taxonomic changes that have occurred over the years (vide Vucetich et al., 2005(vide Vucetich et al., , 2012(vide Vucetich et al., , 2015Deschamps et al., 2007Deschamps et al., , 2013, it is notable the necessity of to increase the data on the fossils of Hydrochoerinae. Since the seminal work "Monografía de los Hydrochoeridae" by Mones (1991), considerable advance about systematics and taxonomy of the South American capybaras have been published mainly on the Neogene taxa (Vucetich et al., 2005(Vucetich et al., , 2012(Vucetich et al., , 2015Deschamps et al., 2007Deschamps et al., , 2013, while few works have focused on the Quaternary forms. Here, we studied the morphology and taxonomy of fossils of Hydrochoerinae from the intertropical region of Brazil, from three fossiliferous sites (Toca dos Ossos and Gruta de Brejões in the State of Bahia; and Lapa Vermelha cave of the Lagoa Santa karst, in the State of Minas Gerais). ...
In this work, new fossils of Hydrochoerinae rodents (Caviomorpha: Caviidae: Hydrochoerinae) from the
Quaternary of the intertropical region of Brazil are described, almost 180 years after the first fossils of these
animals were found in Lagoa Santa, Minas Gerais. The fossils studied herein were collected in caves of States of
Bahia (Toca dos Ossos and Lapa dos Brejões) and Minas Gerais (Lapa Vermelha cave, Lagoa Santa karst). The
analyzed material is assigned to the extinct large rodent Neochoerus sulcidens and is composed of skull portion,
upper and lower cheek teeth, mandible, humerus, innominate, femur, tibia, and calcaneus. The specimens were
assigned to this taxon based on the presence of an M3 with 14 prisms; incisor alveolus reaching the pr. II do m2;
anteriormost level of the palatine at the level of the Pr. II of the M2; and larger size than the living species. The
p4 is mesiodistally longer than the m1 and m2, distinct from previous interpretations in which the mesiodistal
length of the p4 of N. sulcidens would be smaller than the m2, indicating the presence of a variable character.
Except for the differences in size, the postcranial bones of N. sulcidens are quite similar to H. hydrochaeris.
... and H.S.E.) are oblique, as in P. novum. This character is different in the species from Farola Monte Hermosa, P. perturbidum, in which the lobes are subequal and the fissures are perpendicular to the anteroposterior axis (Deschamps et al. 2007(Deschamps et al. , 2012(Deschamps et al. , 2013Cruz et al. 2014;Vucetich et al. 2014aVucetich et al. , b, 2015. Remarks: Most materials here reporter are under study and were presented by Brizuela and Cruz (2013) and Cruz et al. (2014). ...
... This vertebrate assemblage disagrees with the biochronology (based mainly on mammals) from South America represented principally in records of the Atlantic Coast. The last taxonomic and biostratigraphic studies of the giant capybaras (Deschamps et al. 2007, 2013, Vucetich et al. 2014a, 2014b, and references therein) based on the dental evolution of the family Hydrochoeridae concluded that this group of rodents is a very good biochronologic indicator. In these works Phugatherium novum is recognized only for the Chapadmalal Formation (4 to 3.3 Ma); this is Chapadmalalan Stages/Ages (late Zanclean). ...
The “Horizonte Brocherense” sensu Castellanos was created on the basis of a mammal assemblage recovered from the San Alberto Valley and Los Reartes Valley (Córdoba, Argentina). This mammal association was placed in the “Uquian Stage” (early Pliocene) according to the stratigraphic scheme proposed by Castellanos in 1944. Later, different authors considered this association to belong either to the Montehermosan Stage/Age (early Pliocene) or Huayquerian Stage/Age (late Miocene), based on more updated stratigraphic schemes. Here, we present new vertebrates recovered from the type locality (San Alberto or Traslasierra Valley) of the Brochero Formation; we provide the first paleoenvironmental interpretation for this unit, and discuss the age of the fauna and its bearing sediments. As the main result, this work contributes to the knowledge of the Pliocene faunas, providing the first records of some anurans, snakes, and mammals for the Brochero Formation, and the biostratigraphic and chronological implications of such findings when comparing the fossil assemblage with its counterparts from South America.
... They have semiaquatic habits, and live in groups usually ranging in size from two to 30 individuals (Dunnum 2015). They have characteristic euhypsodont, multilaminated cheek teeth (Novak 1991;Deschamps et al. 2007). The phylogenetic relationships of capybaras with other cavioid rodents and the status of hydrochoerids have been revised during the last years (Rowe and Honeycutt 2002;Vucetich and Pérez 2011;Upham and Patterson 2015;Pérez et al. 2018, and references therein). ...
... The fossil record of capybaras (that is, hydrochoerines excluding 'cardiomyines') goes back to the late Miocene, and many taxa were described since the 19th century (Ameghino 1883a, b;Rovereto 1914;Kraglievich 1930;Rusconi 1933Rusconi , 1935Rusconi , 1944Pascual and Bondesio 1963;Francis and Mones 1965a, b;Bondesio 1985a, b;Mones 1991;among others), but revisions such as those by Mones (1984) and, more recently, Vucetich et al. (2005Vucetich et al. ( , 2012Vucetich et al. ( , 2014aVucetich et al. ( , b, 2015 and Deschamps et al. (2007Deschamps et al. ( , 2009) have evidenced a great taxonomic overestimation due to ontogenetic variation that had not been previously evaluated; consequently, these authors drastically reduced the known diversity of hydrochoerines, especially for the late Miocene-Pliocene interval. ...
... Within the late Miocene, the oldest species is Cardiatherium chasicoense Pascual and Bondesio, 1968 from the Chasicoan SALMA, which is known from the type locality Arroyo Chasicó (Buenos Aires Province) as well as from the lower levels of the Loma de Las Tapias Formation in San Juan Province (Contreras 2000;Contreras et al. 2001;Deschamps et al. 2007Deschamps et al. , 2009Contreras and Baraldo 2011). In turn, the Huayquerian SALMA localities with hydrochoerines are more abundant and the material was re-evaluated by Vucetich et al. (2005). ...
A new hydrochoerine rodent, Cardiatherium calingastaense sp. nov. (Caviidae), is described based on the specimen INGEO-PV 87. It was recovered from the late Miocene Las Flores Formation, cropping out at the Puchuzum locality, San Juan Province, Argentina. The new species is based on a particular combination of characters, among which the following can be highlighted: p4 with internal fissures equally deep as in Cardiatherium paranense, secondary external fissure as in Cardiatherium patagonicum, and lacking the fifth internal fissure and supernumerary internal fissure, as in C. paranense; m3 with a conspicuous labial column in the posterior ramus of the second prism; very deep primary and secondary external fissures in upper cheek teeth, the former producing a labial strong step-shaped profile in M2; sagittal crest on the parietals; bullae small in ventral view; scars of the origin of the masseter medialis muscle with an anterior projection up to the level of the incisive foramen and the maxilla-premaxilla suture. The phylogenetic analysis supports the taxonomic proposal of creating a new species of Cardiatherium and shows C. calingastaense sp. nov. as the sister group of the other species of the genus. The lineage leading to the clade Cardiatherium + largest capybaras would have originated at least during the Chasicoan SALMA (early late Miocene). Cardiatherium calingastaense sp. nov. adds to the previous record of Cardiatherium chasicoense and Cardiatherium paranense in the late Miocene of San Juan and Mendoza provinces, respectively, thus increasing the diversity of capybaras in central-west Argentina.
... pequena variação de tamanho). A exemplo das revisões de hidrochoerideos miocênicos (Vucetich et al. 2005, Deschamps et al. 2007), uma revisão dos táxons quaternários poderá, provavelmente, sinonimizar alguns táxons. ...
Rodentia is one of the most diversified placental mammal group. The members
of this clade inhabit all continents with exception of the Antarctic. Caviomorpha is
a South American group, which appeared in the fossil record during the middle Eocene,
and irradiate during the Cenozoic, mainly in the late Oligocene and middle/late Miocene.
Herein, the Brazilian fossil record of caviomorphs is reviewed. Discussion concerning
morphology, lifestyle, evolution and the implications of the Brazilian fossil record are
provided. Fossils assigned to following groups have been recovered in our country: Erethizontidae
(Erethizontoidea), Echimyidae, Ctenomyidae (Octodontoidea), Caviidae (including
Hydrochoerinae), Dasyproctidae, Cuniculidae (Cavioidea), Chinchillidae, Dinomyidae and
Neoepiblemidae (Chinchilloidea). The fossils from this portion of the continent have told
part of the evolutionary history of Caviomorpha during the late Oligocene, Neogene, and
Quaternary. As future perspectives in the study of Brazilian fossil rodents, it is expected
that collection of new specimens with stratigraphic control, review of fossils housed in
scientific collections, and increase in the knowledge on the morphology of the taxonomic
units, will contribute to a better understanding of the diversity and evolution of this group.
... Comments. Neogene capybaras have been reviewed in the last few years (e.g., Vucetich et al. 2005Vucetich et al. , 2012Vucetich et al. , 2014Deschamps et al. 2007Deschamps et al. , 2013 reducing their diversity to four species of a single genus: Cardiatherium chasicoense (Pascual and Bondesio, 1968), Cardiatherium patagonicum Vucetich et al., 2005, Cardiatherium paranaense (Ameghino, 1883), and Cardiatherium orientalis (Francis and Mones, 1965). In the AC, the first remains of hydrochoerids were described by Frailey (1986) who reported remains of C. orientalis (= Kiyutherium orientalis Francis and Mones, 1965) based on isolated cheek teeth from the Acre River. ...
... The specimens have an M3 with six prisms. Considering the evolutionary context in which the number of prisms increases in cavioids with time (Deschamps et al. 2007), the specimens here reported seem to show more plesiomorphic traits than C. paranaense and C. orientalis (7-8 prisms), and C. patagonicum (10-11 prisms), resembling C. chasicoense (6 prisms) as diagnosed by Deschamps et al. (2007). In this sense, these specimens have more affinities with C. chasicoense, the oldest species of this genus, than with other previously described species. ...
... The specimens have an M3 with six prisms. Considering the evolutionary context in which the number of prisms increases in cavioids with time (Deschamps et al. 2007), the specimens here reported seem to show more plesiomorphic traits than C. paranaense and C. orientalis (7-8 prisms), and C. patagonicum (10-11 prisms), resembling C. chasicoense (6 prisms) as diagnosed by Deschamps et al. (2007). In this sense, these specimens have more affinities with C. chasicoense, the oldest species of this genus, than with other previously described species. ...
The fossil-bearing stratigraphic sections of the Solimões Formation (southwestern Brazilian Amazonia) are
exposed mainly along the Juruá, Purus, and Acre rivers, and in road cuts. These deposits have provided fossils of the four main lineages of Caviomorpha – Cavioidea, Erethizontoidea, Octodontoidea, and Chinchilloidea, contributing to the understanding on the evolution of tropical Neogene rodents. Herein, our knowledge about fossil rodents from this region is reviewed. New specimens are recorded, including taxa mentioned for this region for the first time, such as basal cavioids, Dolichotinae, Caviodon (Hydrochoeridae), and Drytomomys (Dinomyidae). Unfortunately, the deposits have no absolute ages, and based on palynological data and the biochronology of several taxa (mainly mammals), the encompassed fauna has been constrained to the late Miocene. However, some rodent lineages recorded here seem to be more related to older faunas, from the middle Miocene and Paleogene. Regarding the biogeographic and paleoenvironmental affinities, most of the Neogene rodents from the Acre region show more similarities to those from the Entre Rios, Argentina, and Urumaco, Venezuela, where wet environments were present during Neogene times. An increase in prospecting along southwestern Amazonian rivers looking for rodents (among other vertebrates) associated with methods to better constrain the ages of these faunal assemblages will contribute to a better understanding of the evolution of the tropical rodents as well as the stratigraphy and age of that portion of the basin.
... The fossil record of hydrochoerines is abundant, particularly for the late Miocene of temperate South America. Fossil hydrochoerines include basal forms traditionally named as Bcardiomyines^(middle Miocene -Pliocene) and a more derived clade, the capybaras, that includes numerous species of Cardiatherium, Hydrochoerus, Neochoerus, and the largest hydrochoerines, Phugatherium and Hydrochoeropsis (Vucetich et al. 2005(Vucetich et al. , 2015bDeschamps et al. 2007Deschamps et al. , 2009Deschamps et al. , 2013Vucetich and Pérez 2011;Pérez et al. 2014). The hydrochoerines are recorded from the middle Miocene to the present, mainly in high latitudes of South America (from Argentina including northern Patagonia, Uruguay, Chile, Bolivia; see Deschamps et al. 2013). ...
... As in all hydrochoerines, the cheek teeth are euhypsodont. The p4 is trilobed, the P4-M2 are bilobed, and the M3 is multilaminated with cement in the flexus/ids, and the enamel is interrupted along the labial wall of each lobe (or prism) of the upper molars (Mones 1991;Vucetich et al. 2005Vucetich et al. , 2014Vucetich et al. , 2015bDeschamps et al. 2007;Pérez et al. 2014). ...
... Significance of Pliocene Capybaras in the Guajira Peninsula The subfamily Hydrochoerinae is recorded from the middle Miocene in La Venta Colombia (Vucetich et al. 2015a) and in Patagonia (Vucetich and Pérez 2011). During the early late Miocene of temperate South America, the most basal genera of hydrochoerines (Procardiomys, Cardiomys, Xenocardia; Pérez et al. 2014;Vucetich et al. 2015a, b), and the derived Cardiatherium chasicoense (Deschamps et al. 2007(Deschamps et al. , 2013 are recorded. From this time, the fossil record of hydrochoerines is abundant and relatively continuous, recording several species of Caviodon and Cardiatherium in the late Miocene (Rovereto 1914;Candela 2005;Vucetich et al. 2005Vucetich et al. , 2010Deschamps et al. 2009Deschamps et al. , 2013. ...
One of the most striking components of the modern assemblage of South American mammals is the semiaquatic capybara (Caviidae, Hydrochoerinae), the biggest rodent in the world. The large hydrochoerines are recorded from the middle Miocene to the present, mainly in high latitudes of South America. Although less known, they are also recorded in low latitudes of South America, and in Central and North America. We report the first record of capybaras from the late Pliocene of Colombia, found in deposits of the Ware Formation, Guajira Peninsula in northeastern Colombia. We analyze the phylogenetic position within Caviidae, the possible environmental changes in the Guajira Peninsula, and the implications of this finding for the understanding of the Great American Biotic Interchange. The morphological and phylogenetic analyses indicate that the hydrochoerine of the Guajira Peninsula is a new species, ?Hydrochoeropsis wayuu, and this genus is most closely related to Phugatherium. According to the latest phylogenetic results, this clade is the sister group of the lineage of the recent capybaras (Neochoerus and Hydrochoerus). ?Hydrochoeropsis wayuu is the northernmost South American Pliocene hydrochoerine record and the nearest to the Panamanian bridge. The presence of this hydrochoerine, together with the fluvio-deltaic environment of the Ware Formation, suggests that during the late Pliocene, the environment that dominated the Guajira Peninsula was more humid and with permanent water bodies, in contrast with its modern desert habitats.
