Browsing by Autor "Federico Anaya"

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A new middle Miocene hegetotheriid (Notoungulata: Typotheria) and a phylogeny of the Hegetotheriidae
(Taylor & Francis, 2006) Darin A. Croft; Federico Anaya
ABSTRACT A new species of hegetotheriid notoungulate, Hemihegetotherium trilobus, is described from the middle Miocene (Laventan SALMA) Quebrada Honda Fauna of southern Bolivia. It differs from all previously described hegetotheriines in possessing a distinctly trilobed m3, a character state previously recorded only in pachyrukhine he-getotheriids. It further differs from other species of Hemihegetotherium in having a proportionately larger p2 and in overall size (being smaller than H. achataleptum and larger than H. torresi). A phylogenetic analysis of hegetotheriid genera coded for 26 characters supports referral of this species to Hemihegetotherium, but does not support the monophyly of Hegetotheriinae; the monophyly of Pachyrukhinae (including Prosotherium and Propachyrucos) is strongly supported. The resulting tree suggests that the lack of tibiofibular fusion in Oligocene pachyrukhines is a secondarily derived trait, but additional postcranial data are needed to provide a stronger test of this hypothesis. Hemihegetotherium trilobus is the most abundant ungulate at Quebrada Honda and is the only species of hegetotheriid present. This contrasts with most other South American paleofaunas in which pachyrukhines are more common than hegetotheriines (e.g., Arroyo Chasicó) and/or other small notoungulates are more common than hegetotheriids (e.g., Chucal, Nazareno). Although the absence of pachyrukhines at Quebrada Honda may be due to a lack of suitable habitat, it is also possible that pachyrukhines had not dispersed north to southern Bolivia by the middle Miocene. Further investigations of Quebrada Honda may help discriminate between these two alternatives and should also help clarify the biogeographic histories of other Miocene taxa.
A new proterotheriid (Mammalia, Litopterna) from the Salla Beds of Bolivia (upper Oligocene): phylogeny and litoptern patellar pit knee locks
(Taylor & Francis, 2022) Bruce J. Shockey; Emily White; Federico Anaya; Andrew J. McGrath
The Salla Beds of Bolivia reveal a rich, late Oligocene (Deseadan, South American Land Mammal “Age”) fauna composed of at least 50 mammalian species. Many taxa (e.g., rodents and typotherian notoungulates) are represented by dozens to hundreds of specimens. Litopterns are much less common but are represented by one macraucheniid and two adianthid species. Until now, only fragmentary postcrania of proterotheriids have been described from Salla. The recent discovery of a maxillary fragment with two molars, examination of previously recovered mandibular fragments, and a phylogenetic analysis, allow us to recognize Promylophis cifellii gen. et sp. nov. It is characterized by small size, absence of a metaconule on M1–2, and lower molars with a short “paracristid” and reduced or absent “paraconid.” Postcranial elements referred to cf. P. cifellii resemble geologically younger (e.g., Miocene) proterotheriids by way of anatomically tridactyl, but functionally monodactyl pes, and distal femora with a supra-trochlear fossa that forms a “patellar pit” that appears to function as a passive stay apparatus for the knee joint. Such a mechanical means of diverting forces from muscle to bone and sinew could save biologically significant amounts of metabolic energy in long-standing animals.
A New Typothere Notoungulate (Mammalia: Interatheriidae), from the Miocene Nazareno Formation of Southern Bolivia
(Asociación Paleontológica Argentina, 2020) Darin A. Croft; Federico Anaya
We describe a new interatheriid notoungulate, Juchuysillu arenalesensis gen. et sp. nov., based on six partial upper and lower dentitions from the early to middle Miocene Nazareno Formation of southern Bolivia. A specimen is also referred to J. arenalesensis from the early middle Miocene (Langhian) locality of Cerdas, Bolivia (ca. 100 km to the northwest). The new species is distinguished by its very small size (ca. 15% smaller than Protypotherium minutum) and the unique combination of shallow ectoloph sulci on P3-4, length of M1 > M2 > M3, trapezoidal upper molars, and absence of a buccal talonid sulcus on m3. A second, larger interatheriid species is present at Nazareno but is not represented by remains sufficiently complete for a more precise identification. A phylogenetic analysis indicates that J. arenalesensis represents a unique lineage within Interatheriinae that diverged after Protypotherium sinclairi but before Miocochilius anomopodus, Caenophilus tripartitus, Miocochilius federicoi, and several species of Protypotherium, including Protypotherium australe. Juchuysillu arenalesensis is one of two small (< ca. 3 kg) typotheres at Nazareno; its body mass is estimated at 1.1 kg. An updated faunal list for the Nazareno Formation includes 19 species of mammals pertaining to seven orders and 15 families; fragmentary turtle (Testudinidae?) and bird (Phorusrhacidae) remains are also present. The precise age of Nazareno Formation vertebrates is unknown, but the presence of at least three notoungulate species shared with Cerdas suggests a similar (∼16–15 Ma) age for the fossil-bearing levels.
A peculiar specimen of Panochthus (Xenarthra, Glyptodontidae) from the Eastern Cordillera, Bolivia
(National Geology and Mining Service, 2023) Francisco Cuadrelli; Martín Zamorano; Daniel Barasoain; Federico Anaya; Alfredo E. Zurita
Panochthus Burmeister is one of the most diversified and widely distributed glyptodonts in the Pleistocene of South America, which includes areas located at high altitudes (>4,000 m a.s.l.). Within the genus, eight species (P. intermedius Lydekker, P. subintermedius Castellanos, P. tuberculatus (Owen), P. frenzelianus Ameghino, P. greslebini Castellanos, P. jaguaribensis Moreira, P. hipsilis Zurita, Zamorano, Scillato-Yané, Fidel, Iriondo and Gillette, and P. florensis Brambilla, López and Parent) are currently recognized. Here, we report a dorsal carapace (UATF-V n/n) from the Pleistocene of the surroundings of Potosí, Bolivia, that shows some morphological particularities when compared to the carapace of P. intermedius, P. frenzelianus, P. subintermedius and P. tuberculatus, including: a) its maximum dorso-ventral diameter is at the anterior half, meanwhile in other species is at mid-point (e.g., Propalaehoplophorus) or at posterior half (e.g., Glyptodon); b) the dorsal profile is different in comparison to other glyptodonts (e.g., Glyptodon, Glyptotherium, Neosclerocalyptus, Propalaehoplophorus); c) the ornamentation pattern of the osteoderms shows a central figure surrounded by small polygonal figures along the most exposed surface of the carapace (except for the mid-dorsal region that shows reticular ornamentation pattern), being different from that of the remaining species: of Panochthus, in which central figures are limited to the caudal/cephalic and most lateral regions of the carapace. In summary, the combination of characters suggests that it could belong to a new species or, alternatively, to P. floriensis or P. jaguaribensis in which the dorsal carapace is not yet known. The phylogenetic analysis confirms its basal position among Panochthus and highlights the importance of these high elevation areas of the Andes in South America in order to understand the complex evolutionary history of glyptodonts.
Analysis of function in the absence of extant functional homologues: a case study using mesotheriid notoungulates (Mammalia)
(Cambridge University Press, 2007) Bruce J. Shockey; Darin A. Croft; Federico Anaya
We use two approaches to test hypotheses regarding function in a group of extinct mammals (Family Mesotheriidae, Order Notoungulata) that lack any close extant relatives: a principle-derived paradigm method and empirically derived analog method. Metric and discrete morphological traits of mesotheriid postcranial elements are found to be consistent with the morphology predicted by a modified version of Hildebrand's paradigm for scratch diggers. Ratios of in-force to out-force lever arms based on skeletal elements indicate that the mesotheriids examined had limbs modified for high out-forces (i.e., they were “low geared”), consistent with the digging hypothesis. Other mesotheriid characters, such as cleft ungual phalanges, a curved olecranon, and a highly modified pelvis (with extra vertebrae incorporated into the sacrum and fusion between the ischium and the axial skeleton) are regarded as being functionally significant for digging and also occur in a variety of extant diggers. Analog methods indicate that mesotheriids share numerous traits common to a variety of extant diggers. Principal component analyses of postcranial elements indicate that mesotheriids consistently share morphometric space with larger extant fossorial mammals: aardvark, anteaters, wombats, and badger. Likewise, discriminant function analyses categorized mesotheriids as fossorial, though imperfectly analogous to the extant diggers analyzed. Thus, both theory-driven and empirically derived methods of estimating function in these extinct taxa support a digging hypothesis for the mesotheriids examined. Adaptations for digging in both the forelimb and sacropelvic functional complexes of mesotheriids provide independent support for the fossorial hypothesis.
Australogale leptognathus, gen. et sp. nov., a Second Species of Small Sparassodont (Mammalia: Metatheria) from the Middle Miocene Locality of Quebrada Honda, Bolivia
(Springer Science+Business Media, 2018) Russell K. Engelman; Federico Anaya; Darin A. Croft
Chronology of Miocene terrestrial deposits and fossil vertebrates from Quebrada Honda (Bolivia)
(Elsevier BV, 2020) Luís Gibert; Alan L. Deino; Luís Valero; Federico Anaya; María Lería; Beverly Z. Saylor; Darin A. Croft
Giant fossil tortoise and freshwater chelid turtle remains from the middle Miocene, Quebrada Honda, Bolivia: Evidence for lower paleoelevations for the southern Altiplano
(Elsevier BV, 2015) Edwin‐Alberto Cadena; Federico Anaya; Darin A. Croft
Grazing in a New Late Oligocene Mylodontid Sloth and a Mylodontid Radiation as a Component of the Eocene-Oligocene Faunal Turnover and the Early Spread of Grasslands/Savannas in South America
(Springer Science+Business Media, 2010) Bruce J. Shockey; Federico Anaya
Lithostratigraphy, chronostratigraphy, and sedimentary environments of the middle Miocene Quebrada Honda Basin in southern Bolivia and implications for Andean climate and uplift
(Elsevier BV, 2022) Beverly Z. Saylor; Angeline M. Catena; Daniel I. Hembree; Federico Anaya; Darin A. Croft
Magnetic polarity stratigraphy of Inchasi: a Pliocene mammal-bearing locality from the Bolivian Andes deposited just before the Great American Interchange
(Elsevier BV, 1993) Bruce J. MacFadden; Federico Anaya; Jaime Argollo
Middle Pleistocene age of the fossiliferous sedimentary sequence from Tarija, Bolivia
(Cambridge University Press, 2013) Bruce J. MacFadden; Peter K. Zeitler; Federico Anaya; John M. Cottle
Abstract The highly fossiliferous sediments of the Tolomosa Formation from Tarija, southern Bolivia, represent one of the most important localities in South America that documents the Great American Biotic Interchange. Over the past several decades, chronostratigraphic studies have indicated a middle Pleistocene age for the Tolomosa Formation from ~ 1.1 to 0.7 Ma. This interval correlates to the Ensenadan South American Land Mammal Age as it is characterized from classic localities in Argentina. Recently, however, a new interpretation based on AMS 14 C ages indicates that the fossiliferous sediments from Tarija are latest Pleistocene, i.e., < 44 ka, and thus of Lujanian age. Here we report a new age of 0.76 ± 0.03 Ma (2σ) based on 11 U–Th/Pb and U–Th/He individual determinations from the Tolomosa Formation. This is indistinguishable from the age published from the same ash in 1983, and was originally used to calibrate the magnetostratigraphic section at Tarija. The new age confirms that the age of the Tolomosa Formation is middle Pleistocene, and not latest Pleistocene. The age of the Tarija Fauna has significant implications with regard to the stage of evolution biochronology for Pleistocene fossil mammals in South America, and in particular, the classic and important reference sections in Argentina.
New Chinchillid Rodents (Hystricognathi: Caviomorpha) from Northern Chile and Bolivia Fill a 17-Million-Year Gap in the Pan-Chinchilline Fossil Record
(Springer Science+Business Media, 2021) Darin A. Croft; John J. Flynn; André R. Wyss; Reynaldo Charrier; Federico Anaya
New Data on Miocene Neotropical Provinciality from Cerdas, Bolivia
(Springer Science+Business Media, 2009) Darin A. Croft; Federico Anaya; David Auerbach; Carmala N. Garzione; Bruce J. MacFadden
New fossil materials of the earliest new world monkey, Branisella boliviana, and the problem of platyrrhine origins
(Wiley, 2000) Masanaru Takai; Federico Anaya; Nobuo Shigehara; Takeshi Setoguchi
Branisella boliviana, from the Late Oligocene of Salla, Bolivia, is the oldest fossil platyrrhine monkey discovered. To date, several fossil specimens of Branisella have been obtained, but most of them are fragmentary dentitions, so the animals craniodental morphology is still obscure. During the 1996 field season a pair of upper and lower jaw fragments and another nearly complete mandible were recovered. These new fossil materials reveal the following morphological features in Branisella: 1) P2 is much smaller than P3,4, whereas P2 is relatively small but probably sexually dimorphic; 2) the zygomatic arch protrudes smoothly posterolaterally from the maxillary bone, as in extant Callicebus; 3) the mandibular arcade is nearly V-shaped and the symphysial angle, which is formed by the horizontal plane and the anterior face of mandibular symphysis, is about 40°, i.e., it neither leans as far anteriorly as in callitrichines nor does it stand as vertically as Cebus; 4) upper and lower molars wore down rapidly in life, suggesting a herbivorous diet and the possibility of terrestriality; and 5) dental eruptive sequence is the same as in extant Aotus. As a whole, the dentition of Branisella is very similar to that of Proteopithecus from the Late Eocene of Fayum, Egypt, except in the lower canine morphology, suggesting a close phyletic relationship between them. The origin and early diversification of platyrrhine monkeys might have occurred on the African continent before crossing the Atlantic Ocean. Am J Phys Anthropol 111:263–281, 2000. © 2000 Wiley-Liss, Inc.
New fossil materials of the earliest new world monkey,Branisella boliviana, and the problem of platyrrhine origins
(Wiley, 2000) Masanaru Takai; Federico Anaya; Nobuo Shigehara; Takeshi Setoguchi
Branisella boliviana, from the Late Oligocene of Salla, Bolivia, is the oldest fossil platyrrhine monkey discovered. To date, several fossil specimens of Branisella have been obtained, but most of them are fragmentary dentitions, so the animals craniodental morphology is still obscure. During the 1996 field season a pair of upper and lower jaw fragments and another nearly complete mandible were recovered. These new fossil materials reveal the following morphological features in Branisella: 1) P(2) is much smaller than P(3,4), whereas P(2) is relatively small but probably sexually dimorphic; 2) the zygomatic arch protrudes smoothly posterolaterally from the maxillary bone, as in extant Callicebus; 3) the mandibular arcade is nearly V-shaped and the symphysial angle, which is formed by the horizontal plane and the anterior face of mandibular symphysis, is about 40 degrees, i.e., it neither leans as far anteriorly as in callitrichines nor does it stand as vertically as Cebus; 4) upper and lower molars wore down rapidly in life, suggesting a herbivorous diet and the possibility of terrestriality; and 5) dental eruptive sequence is the same as in extant Aotus. As a whole, the dentition of Branisella is very similar to that of Proteopithecus from the Late Eocene of Fayum, Egypt, except in the lower canine morphology, suggesting a close phyletic relationship between them. The origin and early diversification of platyrrhine monkeys might have occurred on the African continent before crossing the Atlantic Ocean.
New mammal faunal data from Cerdas, Bolivia, a middle-latitude Neotropical site that chronicles the end of the Middle Miocene Climatic Optimum in South America
(Taylor & Francis, 2016) Darin A. Croft; Alfredo A. Carlini; Martín R. Ciancio; Diego Brandoni; Nicholas E. Drew; Russell K. Engelman; Federico Anaya
We provide new and revised identifications of mammals from the early middle Miocene (Langhian age, Colloncuran South American Land Mammal Age [SALMA]) of Cerdas, Bolivia. We also formally name a new typothere notoungulate, Hegetotherium cerdasensis, sp. nov., that can be distinguished by the absence of an external talonid sulcus on m3 and its small size (15–25% smaller than Hegetotherium mirabile). We refer several typothere specimens from Nazareno, Bolivia, to H. cerdasensis, which suggests that the two sites are of similar age. We report the first sparassodont and astrapothere remains from Cerdas. Sparassodont remains include an associated basicranium and mostly complete mandible; the species appears to represent a new, small-bodied borhyaenoid. Astrapothere remains consist of many tooth fragments from a new species of the subfamily Uruguaytheriinae. A partial sloth dentary from Cerdas likely pertains to the subfamily Megatheriinae and is the first report of the family Megatheriidae from the site. A newly discovered peltephilid armadillo specimen includes a partial articulated carapace that supports recognition of the Cerdas taxon as a new species. The two dasypodids of Cerdas (one Euphractini, one Eutatini) represent two new species closely related to undescribed species from the late middle Miocene (Serravallian age, Laventan SALMA) of Quebrada Honda, Bolivia. The mammals of Cerdas indicate that (1) the middle latitudes (southern tropics) contributed significantly to the diversity of Miocene mammal communities in South America; and (2) the Middle Miocene Climatic Optimum was a key factor in the differentiation of South American mammal assemblages.Citation for this article: Croft, D. A., A. A. Carlini, M. R. Ciancio, D. Brandoni, N. E. Drew, R. K. Engelman, and F. Anaya. 2016. New mammal faunal data from Cerdas, Bolivia, a middle-latitude Neotropical site that chronicles the end of the Middle Miocene Climatic Optimum in South America. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2016.1163574.
New Middle Miocene Caviomorph Rodents from Quebrada Honda, Bolivia
(Springer Science+Business Media, 2011) Darin A. Croft; Jennifer Chick; Federico Anaya
New palaeothentid marsupials (Paucituberculata) from the middle Miocene of Quebrada Honda, Bolivia, and their implications for the palaeoecology, decline and extinction of the Palaeothentoidea
(Taylor & Francis, 2016) Russell K. Engelman; Federico Anaya; Darin A. Croft
Paucituberculatan marsupials, particularly members of the family Palaeothentidae, were important components of South American mammal communities during much of the Cenozoic. However, after the late early Miocene, palaeothentid remains are rare in the fossil record, and the group is last recorded at late middle Miocene sites in Colombia, Bolivia and possibly Argentina. Here, we describe new specimens of palaeothentids from one of these late middle Miocene sites, Quebrada Honda, Bolivia, which include: (1) the first described lower dentitions of Acdestis maddeni, which exhibit distinctive features such as a greatly elongated paracristid and a single-rooted m4; (2) the first described late middle Miocene palaeothentines, representing two new species of Palaeothentes, P. serratus sp. nov. and P. relictus sp. nov., distinguished from other species of Palaeothentes by the presence of an anterobasal cingulid and reduced anterior trigonid crest, among other features; and (3) remains of a third new species, Chimeralestes ambiguus gen. et sp. nov., distinguished from other palaeothentids by its combination of a labially positioned cristid obliqua, reduced m4, and sharply curved entocristid. Phylogenetic and palaeoecological analyses show that Quebrada Honda palaeothentids were taxonomically and morphologically diverse and likely spanned a wide range of ecological niches. Combined with the wide geographical distribution of palaeothentoids during the late middle Miocene, this suggests that the disappearance of these marsupials was preceded by an abrupt rather than gradual decline in taxonomic and ecological diversity as well as geographical range.http://zoobank.org/urn:lsid:zoobank.org:pub:DA7E10BA-7203-4F5A-A3AB-F0E7352B101C
New Proterotheriids from the Middle Miocene of Quebrada Honda, Bolivia, and Body Size and Diversity Trends in Proterotheriid and Macraucheniid Litopterns (Mammalia)
(Asociación Paleontológica Argentina, 2020) Andrew J. McGrath; Federico Anaya; Darin A. Croft
In this work, we describe two new species of proterotheriid litopterns, Olisanophus riorosarioensis gen. et sp. nov. and Olisanophus akilachuta sp. nov. from the middle Miocene (Laventan SALMA) of Quebrada Honda, Bolivia. When incorporated into a recently published phylogenetic analysis (40 taxa; 92 characters), they plot as sister taxa, partially supported by their connected metaconule and protocone on M3. Additionally, we revise the taxonomy of two contemporaneous proterotheriids from La Venta, Colombia. ‘Prolicaphrium' sanalfonensis is reassigned to Mesolicaphrium gen. nov., with a prominent protocone on M3 as an autapomorphy of the genus. We revalidate the genus Neodolodus for Neodolodus colombianus, a species referred to ‘Prothoatherium' or Lambdaconus by previous authors. We used the paleotree R package to examine evolutionary trends in diversity and body size (using m1 length as a proxy) in proterotheriid and macraucheniid litopterns in a phylogenetic context. Proterotheriids were more diverse in the Paleogene than their fossil record indicates; their diversity peaked in the early Miocene and gradually declined until the Pleistocene. Macraucheniids experienced two peaks in diversity, in the early and late Miocene, but were still fairly diverse in the Pleistocene, unlike proterotheriids. Multiple proterotheriid lineages became larger during the Paleogene, but body size was roughly static during the Neogene, with no obvious link between phylogeny and size. Macraucheniids can be grouped into three size classes that are phylogenetically conserved and roughly correspond temporally to Eocene (small Polymorphis spp.), Miocene–Pliocene (medium-sized ‘cramaucheniines’ and early macraucheniines, e.g., Theosodon, Promacrauchenia), and Pleistocene (large macraucheniines, e.g., Macrauchenia) species.