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Combining morphological and molecular characters through Bayesian total-evidence dating allows inferring the phylogenetic and timescale framework of both extant and fossil taxa, while accounting for the stochasticity and incompleteness of the fossil record. Such an integrative approach is particularly needed when dealing with clades such as sloths (Mammalia: Folivora), for which developmental and biomechanical studies have shown high levels of morphological convergence whereas molecular data can only account for a limited percentage of their total species richness. Here, we propose an alternative hypothesis of sloth evolution that emphasizes the pervasiveness of morphological convergence and the importance of considering the fossil record and an adequate taxon sampling in both phylogenetic and biogeographic inferences. Regardless of different clock models and morphological datasets, the extant sloth Bradypus is consistently recovered as a megatherioid, and Choloepus as a mylodontoid, in agreement with molecular-only analyses. The recently extinct Caribbean sloths (Megalocnoidea) are found to be a monophyletic sister-clade of Megatherioidea, in contrast to previous phylogenetic hypotheses. Our results contradict previous morphological analyses and further support the polyphyly of "Megalonychidae," whose members were found in five different clades. Regardless of taxon sampling and clock models, the Caribbean colonization of sloths is compatible with the exhumation of islands along Aves Ridge and its geological time frame. Overall, our total-evidence analysis illustrates the difficulty of positioning highly incomplete fossils, although a robust phylogenetic framework was recovered by an a posteriori removal of taxa with high percentages of missing characters. Elimination of these taxa improved topological resolution by reducing polytomies and increasing node support. However, it introduced a systematic and geographic bias because most of these incomplete specimens are from northern South America. This is evident in biogeographic reconstructions, which suggest Patagonia as the area of origin of many clades when taxa are underrepresented, but Amazonia and/or Central and Southern Andes when all taxa are included. More generally, our analyses demonstrate the instability of topology and divergence time estimates when using different morphological datasets and clock models and thus caution against making macroevolutionary inferences when node support is weak or when uncertainties in the fossil record are not considered., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Society of Systematic Biologists.)

By their past and present diversity, rodents are among the richest components of Caribbean land mammals. Many of these became extinct recently. Causes of their extirpation, their phylogenetic affinities, the timing of their arrival in the West Indies and their biogeographic history are all ongoing debated issues. Here, we report the discovery of dental remains from Lower Oligocene deposits ( ca 29.5 Ma) of Puerto Rico. Their morphology attests to the presence of two distinct species of chinchilloid caviomorphs, closely related to dinomyids in a phylogenetic analysis, and thus of undisputable South American origin. These fossils represent the earliest Caribbean rodents known thus far. They could extend back to 30 Ma the lineages of some recently extinct Caribbean giant rodents ( Elasmodontomys and Amblyrhiza ), which are also retrieved here as chinchilloids. This new find has substantial biogeographic implications because it demonstrates an early dispersal of land mammals from South America to the West Indies, perhaps via the emergence of the Aves Ridge that occurred ca 35-33 Ma (GAARlandia hypothesis). Considering both this new palaeontological evidence and recent molecular divergence estimates, the natural colonization of the West Indies by rodents probably occurred through multiple and time-staggered dispersal events (chinchilloids, then echimyid octodontoids (spiny rats/hutias), caviids and lastly oryzomyin muroids (rice rats)).

Recent field efforts in Peruvian Amazonia (Contamana area, Loreto Department) have resulted in the discovery of a late Oligocene (ca. 26.5 Ma; Chambira Formation) fossil primate-bearing locality (CTA-61). In this paper, we analyze the primate material consisting of two isolated upper molars, the peculiar morphology of which allows us to describe a new medium-sized platyrrhine monkey: Canaanimico amazonensis gen. et sp. nov. In addition to the recent discovery of Perupithecus ucayaliensis, a primitive anthropoid taxon of African affinities from the alleged latest Eocene Santa Rosa locality (Peruvian Amazonia), the discovery of Canaanimico adds to the evidence that primates were well-established in the Amazonian Basin during the Paleogene. Our phylogenetic results based on dental evidence show that none of the early Miocene Patagonian taxa (Homunculus, Carlocebus, Soriacebus, Mazzonicebus, Dolichocebus, Tremacebus, and Chilecebus), the late Oligocene Bolivian Branisella, or the Peruvian Canaanimico, is nested within a crown platyrrhine clade. All these early taxa are closely related and considered here as stem Platyrrhini. Canaanimico is nested within the Patagonian Soriacebinae, and closely related to Soriacebus, thereby extending back the soriacebine lineage to 26.5 Ma. Given the limited dental evidence, it is difficult to assess if Canaanimico was engaged in a form of pitheciine-like seed predation as is observed in Soriacebus and Mazzonicebus, but dental microwear patterns recorded on one upper molar indicate that Canaanimico was possibly a fruit and hard-object eater. If Panamacebus, a recently discovered stem cebine from the early Miocene of Panama, indicates that the crown platyrrhine radiation was already well underway by the earliest Miocene, Canaanimico indicates in turn that the "homunculid" radiation (as a part of the stem radiation) was well underway by the late Oligocene. These new data suggest that the stem radiation likely occurred in the Neotropics during the Oligocene, and that several stem lineages independently reached Patagonia during the early Miocene. Finally, we are still faced with a "layered" pattern of platyrrhine evolution, but modified in terms of timing of cladogeneses. If the crown platyrrhine radiation occurred in the Neotropics around the Oligocene-Miocene transition (or at least during the earliest Miocene), it was apparently concomitant with the diversification of the latest stem forms in Patagonia., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Asian tarsiid and sivaladapid primates maintained relictual distributions in southern Asia long after the extirpation of their close Holarctic relatives near the Eocene-Oligocene boundary. We report here the discovery of amphipithecid and eosimiid primates from Oligocene coastal deposits in Pakistan that demonstrate that stem anthropoids also survived in southern Asia beyond the climatic deterioration that characterized the Eocene-Oligocene transition. These fossils provide data on temporal and paleobiogeographic aspects of early anthropoid evolution and significantly expand the record of stem anthropoid evolution in the Paleogene of South Asia.

Concepts, methods, and interest of phylogenetic reconstruction are briefly examined. As large data sets are considered and refutable results are proposed, there is no need to use the argument of authority concerning relationships between taxons. Cladistic analysis in vertebrate palaeontology has gained considerable strength in the last decade, based on sets of hundreds of anatomical characters. One example is selected, which concerns the rhino family, i.e. rhinocerotids. Although underrepresented in recent times, these perissodactyl mammals flourished throughout the Cenozoicera (4 recent genera vs. 50 fossil genera). The main results of a recent cladistic analysis of elasmotheriine rhinocerotids, based on 282 anatomical characters, are listed. Such results concern phylogenetics (monophyly of both elasmotheriines and recent rhinos; branching of elasmotheriines among rhinocerotids) and methodology (definition of a "branching group"; location and processing of homoplasy; influence of taxonomic sampling). The implications are both biostratigraphical and palaeobiogeographical (evolution of the diet and spatial distribution; intercontinental dispersals; ghost lineages and heuristic use of the phylogenetic tree). Finally, forthcoming developments of the available data set for rhinocerotids are examined: controversial phylogenetic relationships among recent rhinos will be refined (thanks to close extinct taxa) and an exhaustive phylogeny of fossil and recent rhinocerotids will be reconstructed (54 genera).

Aim: The Neotropics currently host outstanding levels of species richness, with one‐third of the global tetrapod species. The underlying causes of these extraordinary levels of biodiversity are a topic debated in evolutionary ecology, but the main processes at work remain elusive. Location: Neotropics. Time period: Cenozoic and Mesozoic. Major taxa studied: Tetrapods. Methods: Using global phylogenies for amphibians, birds, lepidosaurs and mammals, biogeographical and time‐variable (trait‐dependent and trait‐independent) diversification models, we examined changes in speciation and extinction rates through time in the Neotropics in relationship to other areas of the world, and estimated the time of Neotropical colonizations. Results: We found that from the origin of lepidosaurs and mammals until the Pliocene (the Miocene for birds), diversification rates within the Neotropics were lower than rates in other regions (i.e., turnover was high). Afterwards, extinction decreased relative to speciation, and Neotropical diversification outpaced diversification in other regions. Dispersal out of the Neotropics also increased after the Pliocene (the Miocene for birds), exceeding into‐the‐Neotropics migrations. For amphibians, diversification rates in the Neotropics have been higher than in other areas through time, and dispersal out of the Neotropics decreased in the Cenozoic. Main conclusions: The common view that the Neotropics are an ancient source of world species diversity, with high in situ speciation, dispersal to other areas and low extinction, might be true only for amphibians. For mammals, birds and lepidosaurs, the Neotropics acted as a diversity sink from their origin until the Miocene–Pliocene (i.e., diversification rates were lower and turnover higher than in other areas). Only afterwards did the region turn into a diversity source. Our study highlights that models accounting for rates of diversification that vary through time could improve our capacity to assess evolutionary dynamics over long time‐scales. [ABSTRACT FROM AUTHOR]

Fossil remains of extinct terrestrial sloths have been discovered in numerous localities throughout the Americas, but knowledge of these animals remains poor in the tropical latitudes in comparison with the austral ones. Even where Pliocene mylodontine sloths are known from North and South America, well-preserved craniodental remains are extremely rare, hindering reliable assessment of their taxonomic assignment and phylogenetic affinities. Here, new craniodental remains of Simomylodon uccasamamensis, from the latest Miocene–Pliocene of the Bolivian Altiplano, are described and compared with those of other Neogene Mylodontinae from South and North America. The resulting morphological observations, combined with morphometric analyses, permit reliable differentiation among these moderate-sized Miocene–Pliocene mylodontids. Simomylodon uccasamamensis appears to be the smallest Pliocene mylodontine, and it is closely related phylogenetically to the late Miocene species Pleurolestodon acutidens. Simomylodon uccasamamensis is also an endemic taxon of the Andean highlands during the Pliocene, with a continuous chronological range extending throughout the Montehermosan, Chapdamalalan and (early) Marplatan South American Land Mammal Ages. This terrestrial sloth may have found its ideal ecological conditions in the Bolivian Altiplano, during a span of time falling between the important South American Late Miocene–Pliocene faunal turnover and the Great American Biotic Interchange around the Pliocene–Pleistocene transition. [ABSTRACT FROM AUTHOR]

We present new material of the selenodont anthracothereHemimeryx blanfordifrom the Oligocene deposits of the Bugti Hills (Balochistan, Pakistan), collected between 1999 and 2002. This is the first undisputed Oligocene occurrence of the species, previously known from the early Miocene of Pakistan. Investigation of the molar enamel microstructure reveals a surprising mono-zonal Schmelzmuster, already detected in some middle to Late miocene selenedont anthracotheres. We include this observation combined with a morphological revision ofH. blanfordiand a cladistic assessment of the dental evidence, to propose a new phylogenetic hypothesis regardingHemimeryxand its close relatives. We confirm the clade including advanced bothriodontines, which we erect to a tribe rank and name Merycopotamini. The South Asian origin of Merycopotamini is consistent with hypothesized subsequent dispersal events of Merycopotamini from Asia to Africa. [ABSTRACT FROM AUTHOR]

Tardigrade xenarthrans are today represented only by the two tree sloth genera Bradypus and Choloepus, which inhabit the Neotropical rainforests and are characterized by their slowness and suspensory locomotion. Sloths have been recognized in South America since the early Oligocene. This monophyletic group is represented by five clades traditionally recognized as families: Bradypodidae, Megalonychidae, Mylodontidae (†), Megatheriidae (†) and Nothrotheriidae (†). A new nothrotheriid ground sloth represented by a dentary and several postcranial elements, Aymaratherium jeani gen. nov., sp. nov., from the early Pliocene locality of Pomata-Ayte (Bolivia) is reported. This small- to medium-sized species is characterized especially by its dentition and several postcranial features. It exhibits several convergences with the 'aquatic' nothrotheriid sloth Thalassocnus and the giant megatheriid ground sloth Megatherium ( M.) americanum, and is interpreted as a selective feeder, with good pronation and supination movements. The tricuspid caniniform teeth of Aymaratherium may represent a transitional stage between the caniniform anterior teeth of basal megatherioids and basal nothrotheriids (1/1C-4/3M as in Hapalops or Mionothropus) and the molariform anterior teeth of megatheriids (5/4M, e.g. Megatherium). To highlight the phylogenetic position of this new taxon among nothrotheriid sloths, we performed a cladistic assessment of the available dental and postcranial evidence. Our results, derived from a TNT treatment of a data matrix largely based on a published phylogenetic data set, indicate that Aymaratherium is either sister taxon to Mionothropus or sister to the clade Nothrotheriini within Nothrotheriinae. They further support the monophyly of both the Nothrotheriinae and the Nothrotheriini, as suggested previously by several authors. [ABSTRACT FROM AUTHOR]

Since the discovery of the megaherbivore Arsinoitherium zitteli Beadnell (early Oligocene of Egypt), the extinct order Embrithopoda has remained an enigmatic group, with disputed affinities among ungulates. In this study, new specimens of Palaeoamasia kansui from the early Palaeogene of Turkey are described and a synthetic dental terminology is proposed for embrithopods. Based on 130 cranial-mandibular and dental characters, the first phylogenetic analysis of embrithopods is carried out in aim to enhance the position of Palaeoamasia within embrithopods. The monophyly of Embrithopoda is confirmed, following the topology ( Phenacolophus ( Namatherium ( Arsinoitheriinae, Palaeamasiinae))). However, phylogenetic relationships between Eurasian embrithopods ( Palaeoamasiinae: Palaeoamasia, Crivadiatherium and Hypsamasia) remain unresolved. The integration of all embrithopod genera within a cladistic analysis encompassing a wider taxonomic sample ( Condylarthra, Afrotheria/ Paenungulata and Laurasiatheria) also supports Embrithopoda as being monophyletic, but questions the position of both Phenacolophus and Namatherium within Embrithopoda. Finally, possible faunal exchange events are proposed based on three hypothesized scenarios between Eurasia and Arabia- Africa during the early Palaeogene. [ABSTRACT FROM AUTHOR]

Gavialoid crocodylians are the archetypal longirostrine archosaurs and, as such, understanding their patterns of evolution is fundamental to recognizing cranial rearrangements and reconstructing adaptive pathways associated with elongation of the rostrum (longirostry). The living Indian gharial Gavialis gangeticus is the sole survivor of the group, thus providing unique evidence on the distinctive biology of its fossil kin. Yet phylogenetic relationships and evolutionary ecology spanning ~70 million-years of longirostrine crocodylian diversification remain unclear. Analysis of cranial anatomy of a new proto-Amazonian gavialoid, Gryposuchus pachakamue sp. nov., from the Miocene lakes and swamps of the Pebas Mega-Wetland System reveals that acquisition of both widely separated and protruding eyes (telescoped orbits) and riverine ecology within South American and Indian gavialoids is the result of parallel evolution. Phylogenetic and morphometric analyses show that, in association with longirostry, circumorbital bone configuration can evolve rapidly for coping with trends in environmental conditions and may reflect shifts in feeding strategy. Our results support a long-term radiation of the South American forms, with taxa occupying either extreme of the gavialoid morphospace showing preferences for coastal marine versus fluvial environments. The early biogeographic history of South American gavialoids was strongly linked to the northward drainage system connecting proto-Amazonian wetlands to the Caribbean region. [ABSTRACT FROM AUTHOR]

In spite of a scarce fossil record and poor diversity, xenungulates cover a wide spatial range throughout South America: a new representative of Carodnia Simpson, 1935, attests to the northernmost occurrence of a carodniid xenungulate, ~4,500km away from previous occurrences (Saõ José de Itaboraí, Rio de Janeiro, Brazil; Chubut Province, Patagonia, Argentina) and very close to the Pacific Coast. A phylogenetic analysis of Xenungulata at the species level shows that Xenungulata and Carodniidae are monophyletic, while Etayoidae are potentially paraphyletic, at least with the selected taxonomic sample. Phylogenetic relationships among Xenungulata are [ Notoetayoa gargantuai, Etayoa bacatensis [ Carodnia sp. nov. [ Carodnia feruglioi, C. cf. feruglioi, C. vieirai]]]. The new species is well differentiated from other xenungulates in having the m3 slightly smaller than m2 in terms of occlusal area and the entoconid and hypoconid almost at the same level on m3. It further differs from all other xenungulates but Etayoa bacatensis in possessing a transverse protolophid on m3. It is distinct from all other representatives of Carodnia in showing a precingulid strongly developed on m2-m3. Referral of the locality to the well-constrained early Eocene Mogollón Formation also confirms (i) the persistence of both carodniid and etayoid xenungulates well after the Paleocene-Eocene transition in South America and (ii) the absence of paleogeographic barrier for such large terrestrial mammals at the scale of South American landmass. [ABSTRACT FROM AUTHOR]

The Middle Miocene has been identified as a time of great diversification in modern lineages now distributed in tropical South America, and when basic archetypal traits defining Amazonia appear, including climatic humid conditions, basic floral physiognomy and phylogenetic composition of modern rainforests. Nonetheless, Middle Miocene localities in South America are poorly known, especially at low latitudes where only one species-rich locality, La Venta in Colombia, has been extensively studied. The present contribution describes the mammal fauna of Fitzcarrald, a new Middle Miocene local fauna from western Amazonia in Peru. Fitzcarrald is correlated with the Laventan South American Land Mammal Age based on the presence of taxa defining the ' Miocochilius assemblage zone' in La Venta. The mammalian fauna of Fitzcarrald comprises 24 taxa among cingulates, folivores, astrapotheres, notoungulates, litopterns, rodents, odontocetes and a possible marsupial. At this time, tropical South America was characterized by the presence of the Pebas megawetland, a huge lacustrine complex that provided unique ecological and environmental conditions most likely isolating northern South America from southern South America. These isolating conditions might have come to an end with its disappearance in the Late Miocene and the establishment of the subsequent Acre system, the predecessor fluvial system of modern Amazonia. Results of faunistic similarity between Fitzcarrald and other Miocene faunas throughout South America support these scenarios. The Fitzcarrald mammal fauna exhibits first appearance datums and last appearance datums of various taxa, showing that tropical South America has played a crucial role in the evolutionary history and biogeography of major clades, and revealing a more complex biological history than previously proposed, based on the record from the southern cone of the continent. [ABSTRACT FROM AUTHOR]

In recent years, the evolutionary history of rhinoceroses has been extensively developed and clarified, notably with the help of morpho-anatomical and molecular-based phylogenetic analyses. Within Rhinocerotidae, the genus Coelodonta Bronn, 1831, is one of the most representative icons of the Ice Ages, ranging from the Late Pliocene to the latest Pleistocene. Nevertheless, few studies have focused on its phylogeny and the systematic assignment of its Middle Pleistocene representatives is fervently debated. Indeed, the earliest European specimens of Coelodonta are considered as documenting either C. tologoijensis Belyaeva in Vangengejm et al., 1966), of Russian affinities, or an early subspecies of Coelodonta antiquitatis (Blumenbach, 1799), C. a. praecursor Guérin1980. Accordingly, C. antiquitatis would then first occur in the Late Pleistocene or in the Middle Pleistocene depending on the hypothesis. The current work aims to describe and identify cranio-mandibular and postcranial remains of Coelodonta from the Middle Pleistocene Les Rameaux locality, SW France, and to compare them with all Eurasian representatives of the genus, including the oldest European specimens from Bad Frankenhausen. A combination of morphometric and morpho-anatomical phylogenetic analyses strongly supports C. a. praecursor and C. a. antiquitatis as distinct and valid subspecies and allows for the refutation of the taxonomic assignment of the Bad Frankenhausen skull to C. tologoijensis. This work proposes the first comprehensive phylogeny for Coelodonta , further tracing its biogeographical history. • Coelodonta antiquitatis praecursor and Coelodonta antiquitatis are distinctive subspecies. • The Middle Pleistocene rhinocerotid from Les Rameaux is referred to as C. a. praecursor. • Coelodonta tologoijensis is not documented in Western Europe thus far. • Coelodonta antiquitatis appears as early as 0.6 Ma in Western Europe, in Bad Frankenhausen. [ABSTRACT FROM AUTHOR]

A newly discovered, well-preserved skull and associated fragment of a juvenile mandible from the Early Oligocene locality of Poillat (Canton Jura, NW Switzerland), bearing close affinities with the rhinocerotidProtaceratherium albigense(Roman, 1912), are attributed to a new small-sized representative of early diverging Rhinocerotinae,Molassitherium delemontensegen. et sp. nov. Other specimens from Western Europe, formerly questionably referred toEpiaceratheriumAbel, 1910, are assigned to this new genus. Comparison with the previously describedProtaceratheriumAbel, 1910 (including type material) and a phylogenetic analysis highlight the mismatch ofProtaceratherium minutum(Cuvier, 1822) andProtaceratherium albigense(Roman, 1912). Given the topology of the most parsimonious tree, a basal split within Rhinocerotidae coincides with the well-supported divergence of the Elasmotheriinae and Rhinocerotinae clades. Relationships within Rhinocerotinae are [Epiaceratherium bolcenseAbel, 1910 [Epiaceratherium magnumUhlig, 1999 [Molassitheriumgen. nov. [MesaceratheriumHeissig, 1969 [PleurocerosRoger, 1898 [Protaceratherium minutum(Cuvier, 1822) [Plesiaceratherium mirallesi(Crusafont, Villalta and Truyols, 1955) [Aceratheriini, Rhinocerotini]]]]]]]]. The only paraphyletic genus in the analysis isEpiaceratherium, with the earliest OligoceneEpiaceratherium bolcenseAbel, 1910 being sister taxon to an [Epiaceratherium magnumUhlig, 1999, Rhinocerotinae] clade. In the single most parsimonious tree,Molassitheriumgen. nov., included within the early diverging Rhinocerotinae, forms a clade encompassingMolassitherium delemontensegen. et sp. nov. and the type speciesMolassitherium albigensecomb. nov. The range ofMolassitherium delemontensegen. et sp. nov. is so far restricted to the late Early–early Late Oligocene interval in Western Europe (Germany, Switzerland, France; ‘late MP22’–MP25). [ABSTRACT FROM PUBLISHER]

Rhinocerotids are particularly abundant and diversified in Neogene deposits of the Indian subcontinent, but their systematics is far from being well defined. Based on the revision of old collections and new findings from the Early Miocene of the Bugti Hills and Zinda Pir, Pakistan, ‘ Aceratherium blanfordi Lydekker, 1884’ is a chimera, consisting of two dentally convergent but postcranially distinct rhinocerotid taxa: Pleuroceros blanfordi and Mesaceratherium welcommi sp. nov. Postcranial features appear to be much more diagnostic than craniodental morphology in this case. A phylogenetic analysis based on 282 morphological characters scored for 28 taxa (four outgroups and ingroup including both taxa of interest and a ‘branching group’) strengthens this statement and supports Pleuroceros and Mesaceratherium as monophyletic genera within Rhinocerotinae. Both genera are recognized for the first time outside Europe. In the Bugti Hills, P. blanfordi and M. welcommi are part of an exceptionally diversified rhinocerotid fauna, with up to nine species associated in the same locality (Kumbi 4f). This rhinocerotid assemblage confirms the earliest Miocene age (Agenian/Aquitanian) of the upper member of the Chitarwata Formation as a whole. Coeval homotaxic rhinocerotid faunas from Europe (France, Czech Republic) and East Africa (Uganda, Kenya) support broad and sustainable rhinocerotid interchanges amongst South Asia, Europe, and Africa under compatible environmental conditions throughout earliest Miocene times. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160, 139–194. [ABSTRACT FROM AUTHOR]

Middle Miocene chalicotheriine remains from France have played an important part in the palaeontological history of chalicotheres. For example, both the first known skull and first complete individual come from Sansan (MN 6, Gers, France). Nevertheless, these remains have never been described in detail until now. Firstly, cranial remains of Anisodon grande from Sansan are described. A review of nomenclatural problems supports Anisodon Lartet, 1851 as the appropriate genus name for this species and a new lectotype is designated. Secondly, the description of new remains of Chalicotherium goldfussi from Saint-Gaudens (MN 8, Haute-Garonne, France) considerably increases knowledge of this taxon. Thirdly, a skull from La Grive Saint-Alban (MN 7–8, Isère, France) is reassessed. A new cladistic analysis of the Chalicotheriinae is proposed incorporating these new data. This analysis, including 12 taxa and 51 cranio-mandibular and dental characters, supports the division of Middle and Late Miocene chalicotheriines into two clades. A novel pattern of relationships is proposed and the systematics is revised. However, chalicotheriine relationships remain labile because of the need for both a revision of pre-Middle Miocene taxa and the addition of postcranial data. © 2007 The Natural History Museum, London. Journal compilation © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society, 2007, 151, 577–608. [ABSTRACT FROM AUTHOR]

Eight elasmotheriine rhinocerotid species have been described from the Middle Miocene of China and Mongolia. In this paper a revised taxonomy is presented based on direct observation and comparison of the available material. A phylogenetic analysis based on 282 morphological characters has led to the reappraisal of Procoelodonta Matthew, 1931, Caementodon Heissig, 1972 and Huaqingtherium Huang & Yan, 1983. The genus Procoelodonta is split into three subgenera: P. (Procoelodonta ) Matthew, 1931, P. (Begertherium ) Beliaeva, 1971, and P. (Pasalarhinus subg. n). The genus Caementodon is split into two subgenera: C. (Caementodon ) Heissig, 1972 and C. (Beliajevina ) Heissig, 1974. Four species are assumed to have occurred in the Middle Miocene within the area studied: Procoelodonta (Procoelodonta ) mongoliense (Osborn, 1924), ‘P. ’ (Begertherium ) borissiaki (Beliaeva, 1971), ‘Caementodon ’ (Beliajevina ) fangxianense (Yan, 1979) and Huaqingtherium lintungense (Zhai, 1978) (=‘Caementodon tongxinensis ’ Guan, 1988 =‘Huaqingtherium qiui ’ Guan, 1993 =‘Hispanotherium tungurense ’ Cerdeño, 1996). Shennongtherium hypsodontus Huang & Yan, 1983 is removed from the Elasmotheriina, owing to dental characters which suggest that it is a teleoceratine. The distribution of the main characters later seen in Elasmotherium is briefly discussed. The persistence and diversity of the Elasmotheriina throughout the Middle Miocene help explain how minute brachyodont animals gave rise to the mammoth-sized hypsodont Elasmotherium. [ABSTRACT FROM AUTHOR]

A new species of Hispanotherium from the Early Miocene of Spain is named. Its phylogenetic relationships within Elasmotheriina are discussed owing to a cladistic analysis. H. grimmi Heissig, 1974 and H. beonense Antoine, 1997 are consequently integrated in the genus Hispanotherium, together with the type species H. matritense and the new species, which differs from other ones by several dental and postcranial features. The westward dispersal of the Elasmotheriina from Asia toward Western Europe during the Early Miocene is hypothesized. To cite this article: P.-O. Antoine et al., C. R. Palevol 1 (2002) 19–26. [Copyright &y& Elsevier]

Post Cretaceous–Paleogene (K–Pg) boundary continental ecosystems of Europe host a distinctive assemblage of derived neosuchians related to modern semi-aquatic lineages, including the alligatoroid Diplocynodon and the crocodyloid Asiatosuchus but also a less well-understood group known as the Planocraniidae. Yet, uniquely in its faunal composition, Europe also preserves some of the last representatives of Notosuchia, a group that previously underwent a successful radiation in terrestrial ecosystems of the Cretaceous, especially in Gondwana. Although Europe harbored a few members of Sebecosuchia during the Cretaceous, their affinities with post-K–Pg forms is not ascertained, in part due to their rare and fragmentary nature on both sides of the stratigraphic boundary. Paleogene European sebecosuchians have been reported from the Eocene of France, Germany, Portugal, and Spain. Resolving their phylogenetic position may shed light on their suspected Gondwanan affinities. Based on new cranial and postcranial remains, we provide a description of the most complete and largest European sebecosuchian to date from the middle Eocene (Bartonian) of Issel and Réalmont, southern France. Dentaneosuchus gen. nov. is proposed to designate the taxon originally described as Atacisaurus crassiproratus. A phylogenetic analysis recovers Dentaneosuchus crassiproratus as the basalmost branching member of Sebecidae, a clade otherwise known from abundant specimens from the Paleogene and Miocene of South America. Among post-K–Pg sebecids, Dentaneosuchus crassiproratus rivalled in size with Barinasuchus arveloi from the Miocene of Venezuela, demonstrating that sebecids achieved the status of apex predators in terrestrial ecosystems of both Europe and South America. [ABSTRACT FROM AUTHOR]

The article reports a new fossileferous locality at Malengane, in southwestern France that yielded two skulls referred to the anthracotheriid Elomeryx crispus and the rhinocerotid Protaceratherium albigense, and an isolated rodent tooth. It offers a description of this exceptional material to provide new characters to precisely diagnose the species and to propose accurate phylogenetic relationships. Because of the discovery of an upper molar of a theridomyid rodent in the same level, the article then discusses the stratigraphical range and position of this new locality in the local geological context.