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Crivadiatherium iliescui n. sp., nouvel Embrithopode (Mammalia) dans le Paléogène ancien de la dépression de Hateg (Roumanie).
Constin Radulesco and Jean Sudre
Keywords: Embrithopods; Late Eocene; Paleobiogeography; Romania
 
  Abstract

    The investigations undertaken at Crivadia (Hateg Depression, Hunedoara District, Romania), the type locality of Crivadiatherium mackennai RADULESCO el al. (Radulesco, Iliesco et lliesco, 1976), led to the discovery of remains of a new Embrithopod. Close to the above mentioned species, but larger in size, this animal is here described as a new species of Crivadiatherium, C. iliescui. ln addition, the comparison made between the forms indicated above and Palaeaamasía kansui OZANSOY from the Eocene deposits of Anatolia (Ozansoy, 1966; Sen et Heintz, 1979) showed that the latter species included a heterogeneous material; this permitted us to distinguish the form in the Anatolian locality Ciçekdag-Arabin Kôyü under the name Palaeoamasia sp. The geographical distribution and diversity of the Embrithopod species under discussion (Balkan, Anatolia) support the idea of an eurasiatic origin of this group and seem to suggest the existence during the Eocene of a particular faunal province in south-eastern Europe. 


  Article infos

Published in Vol. 15, Fasc. 3 (1985)

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Cricetid rodents from Siwalik deposits near Chinji village. Part I: Megacricetodontinae, Myocricetodontinae and Dendromurinae.
Everett H. Lindsay
Keywords: Dendromurinae; Megacricetodontinae; Middle Miocene; Myocricetodontinae; Rodents; Siwalik
 
  Abstract

    Seventeen species of cricetid rodent are recognized and described from lower and middle Siwalik deposits in the Potwar Plateau of Pakistan. These species are grouped in three categories, characterized as subfamilies (e. g., Megacricetodontinae, Myocricetodontinae, and Dendromurinae); an additional and more abundant category of rodents from these deposits, the Democricetodontinae, is excluded from this study, and will be described in a later study. Fifteen of the species are new, and four new genera are described. The Siwalik cricetid taxa are : Megacricetodon aquilari, n. sp.; Megacricetodon sivalensis, n. sp.; Megacricetodon daamsi, n. sp.; Megacricetodon mythikos, n. sp.; Punjabemys downsi, n. gen. & n. sp.; Punjabemys leptos, n. gen. & n. sp.; Punjabemys mikros, n. gen. & n. sp.; Myocricetodon sivalensis, n. sp.;  Myocricetodon sp.; Dakkamyoides lavocati, n. gen. & n. sp.; Dakkamyoides perplexus, n. gen. & n. sp.; Dakkamys asiaticus, n. sp.; Dakkamys barryi, n. sp.; Dakkamys sp.; Paradakkamys chinjiensis, n. gen. & n. sp.; Potwarmus primitivus, n. gen.; and Potwarmus minimus, n. gen. & n. sp. This diverse record of middle Miocene small mammals illuminates a profound radiation of cricetid rodents in southem Asia, the effects of which were felt in Europe and Africa as well as the rest of Asia. 


  Article infos

Published in Vol. 18, Fasc. 2 (1988)

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Arvicolinae (Rodentia) du Pliocène terminal et du quaternaire ancien de France et d'Espagne.
Jacques Michaux
Keywords: Arvicolinae; France; Pleistocene; Pliocene; Spain

doi: 10.18563/pv.4.5.137-214
 
  Abstract

    Two steps can be distinguished in the history of the first invasion of western and south western Europe by the arvicolines. The first step corresponds to the installation of these rodents with the immigration of Promimonys inxuliferus Kowalski, then of Mimomys stehlini Kormos and of Mimomys gracilis (Kretzoi). The second is characterized by the establishment of a geographic differentiation in the arvicoline fauna between the south of France and Spain, from where are described new species of Mimomys (Mimamys cappettai, Mimomys septimanus, Mimonys medasensis), and the rest of France, where are found only elements already known from central Europe or England (Mimomys polonicus Kowalski, Mimomys pliocaenicus F. Major, Mimomys reidi Hinton, or forms very close to the latter). This geographic differentiation, which is very certainly the consequence of the division of Europe into distinct climatic provinces, one of them being the southern province comprising at least Spain and southern France, could result from a cladogenetic evolution of Mimomys stehlini and Mimomys gracilis after their immigration. The present work is also a contribution to the search for correlations between the diverse micromammal localities of the latest Pliocene (or early Villafranchian) and of the early Quaternary of Europe. 


  Article infos

Published in Vol. 04, Fasc. 5 (1971)

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Dilambodont Molars :a functional interpretation of their evolution
Percy M. Butler
Keywords: Convergent evolution; Dilambdodont; Molar function; Molar teeth
 
  Abstract

    In dilambdodont molars the primitive crest between paracone and metacone (centrocrista) is represented by a pair of crests that join the mesostyle (postparacrista, premetacrista). The cutting action of these crests against the crests of the hypoconid is described. Dilambdodonty is a derived adaptation for greater cutting efficiency. It has evolved several times and in more than one way. 


  Article infos

Published in Vol. 25, Fasc. 2-4 (1996)

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Two new scyliorhinid shark species (Elasmobranchii, Carcharhiniformes, Scyliorhinidae), from the Sülstorf Beds (Chattian, Late Oligocene) of the southeastern North Sea Basin, northern Germany.
Thomas Reinecke
Keywords: Chattian; Elasmobranchii; North Sea Basin; Scyliorhinidae; Scyliorhinus

doi: 10.18563/pv.38.1.e1
 
  Abstract

    Based on isolated teeth two new scyliorhinid shark species, Scyliorhinus biformis nov. sp. and Scyliorhinus suelstorfensis nov. sp., are described from the Sülstorf Beds, early-middle Chattian, of Mecklenburg, northeastern Germany. They form part of a speciose assemblage of necto-benthic sharks and batoids which populated the warm-temperate to subtropical upper shelf sea of the south-eastern North Sea Basin. 


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Published in Vol.38-1 (2014)

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Revision of the family Cephalomyidae (Rodentia, Caviomorpha) and new cephalomyids from the early Miocene of Patagonia.
Alejandro Kramarz
Keywords: Cephalomyidae; Lower Miocene; Patagonia; Rodentia; Soriamys; Systematics
 
  Abstract

     A new genus of hystricognath rodent with two new species, Soriamys gaimanensis and Soriamys ganganensis, from the Colhuehuapian Age (Early Miocene), Sarmiento Formation, of Patagonia is described. The first species comes from the south barranca of the valley of Rio Chubut, near Gaiman locality (Chubut Province). It is known through a great number of dental remains in different stages of wear. The teeth are protohypsodont, with cement in the principal valleys. P4 are simpler, more oval inoutline and without a differentiated hypocone-hypoflexus. Upper molars are pentalophodont in early stages of wear and become bilobated in middle and advanced stages; M3 have a temporary third posterior lobe due to the maintenance of the braquiflexus on the posterior wall of the tooth. Lower teeth have a completely asymrnetrical pattern in relation to the uppers. The molars are trilophodont, with only one complex crest in the trigonid composed of the fusion of the anterolophid and mesolophid. The dp4 have a derived pentalophodont pattern due to the loss or fusion of the mesolophid and the development of an accessory transverse crest between the anterolophid and metalophid. The second species is known through a complete skull and jaw and other skull fragments with the dentition, proceeding from Pampa de Gan Gan, Chubut province. Respect to the first species, the teeth are higher crowned, with an earlier occlusal simplification and a third posterior lobe of M3 more developed and persistent. The skull and jaws show many chinchilloid characters, such as jugal bone with an ascending process, concave palate, very prominent dorsal shelf of the masseteric fossa, nasolachrymal duct opened laterally on the maxillary and very developed lateral mandibular fossa. Moreover, Soriamys is closely related to Cephalomys by sharing a similar asymmetric dental pattern and other dental and mandibular characters. These two genera constitute a natural group, the Cephalomyidae, with peculiar dental characters, like the asymmetric pattem of the upper and lower teeth; Cephalomyopsis, and probably Litadontomys, can be considered part of this group. Scotamys and Perimys constitute a distinct lineage (the Neopiblemidae or Perimyidae), more closely related to the chinchillids. Many characters shared by cephalomyids, eocardiids and caviids suggest a closer affinity between the Chinchilloidea and the Cavioiidea as a whole. Abrocoma shows also an asymmetric dental pattern and other chinchilloid features that suggest some degree of relationship with the cephalomyids, still not well determined. 


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Published in Vol. 30, Fasc. 1-2 (2001)

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The Gliridae (Mammalia) from the oligocene (MP24) of Gröben 3 in the folded molasse of southern Germany
Undine Uhlig
Keywords: Biostratigraphy; Cyrena Beds; folded molasse; Germany; Gliridae; level MP 24; Mammals; Oligocene; Palaeoecology
 
  Abstract

    This study describes four taxa of Gliridae from the Oligocene mammal locality Gröben 3: Gliravus tenuis BAI-ILO, 1975, Bransatoglis micio (MISONNE, 1957), B. planus (BAHLO, 1975) and B. heissigi n. sp. Gliravus tenuis from Gröben 3 is somewhat more advanced than the type population found in Heimersheim. This confirms previous research suggesting that Gröben 3 should be dated earlier than Heimersheim (MP 24). The first documented occurrence of B. mício around level MP 24 was found in Gröben 3. An abundance of tooth material from B. planus in Gröben 3 makes it possible, for the first time, to observe evolutionary stages within this species from MP 21 until MP 28. B. heissigi n. sp. is restricted to level MP 24. This species is located between B. mísonnei (MP 20 - 23) and Microdyromys praemurinus (MP 25 - 28). Within the lineage Bransatoglis bahloi - B. misonnei - B. heissigi, a decrease in size is noticeable.

      


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Published in Vol. 30, Fasc. 3-4 (2001)

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Lower Paleogene crocodilians from Silveirinha, Portugal.
Miguel T. Antunes
Keywords: ?Upper Paleocene / Lowermost Eocene; Crocodilians; Ecology; Portugal
 
  Abstract

    The presence at Silveirinha of one of the earliest, ? Late Paleocene or Lowermost Eocene, european representatives of the genus Diplocynodon is based mostly on isolated bones and teeth (often from juveniles). This small-sized form is the only crocodilian so far recognized in this site. The longevity of Diplocynodon in Portugal becomes much extended; the genus survived there until the Middle Miocene at least. A discussion on the possible affinities with other eocene Díplocynodon and especially those from Cubillos-Valdegallina (Zamora, Spain) is presented. On the other hand, differences have been detected in comparison with: Díplocynodon tormis, from the middle Eocene of the Douro basin in Spain, which may belong to another phyletic line; and the aff. Diplocynodon from Dormaal (Belgium) and Le Quesnoy (France), nearly contemporaneous of Silveirinha. The Silveirinha Diplocynodon and many other data strongly suggest moist, subtropical, quite limited in space environments related to an alluvial plain crossed by small, meandering channels. 


  Article infos

Published in Vol. 32, Fasc. 1 (2003)

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First record of dinosaur eggshells and teeth from the north-west african Maastrichtian (Morocco).
Géraldine Garcia, Rodolphe Tabuce, Henri Cappetta, Bernard Marandat, Ilhem Bentaleb, Aziza Benabdallah and Monique Vianey-Liaud
Keywords: Africa; amniotic eggshells; Maastrichtian; Morocco; theropod teeth
 
  Abstract

    We report the discovery of amniotic eggshells and theropod teeth from the Late Cretaccous  period in Morocco.The megaloolithid family represents the only known dinosaur egg remains in the north part of Africa and attests indirectly to the occurrence of sauropod dinosaurs (titanosaurids) in the Maastrichtian of Africa.

      


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Published in Vol. 32, Fasc. 2-4 (2003)

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Les poissons crétacés et tertiaires du bassin des Iullemmeden (République du Niger)
Henri Cappetta
Keywords: Actinopterygians; Cenozoic; Cretaceous; Dipnoans; Selachians
 
  Abstract

    The present work is devoted to the study of the Cretaceous and Tertiary fishes (teeth of Selachians, Actinopterygians and Dipnoans) collected during a recent expedition in Niger. The Maestrichtian localities have yielded a new genus and a new subspecies of Selachian: Igdabatis sigmodon nov. gen., nov. sp. and Lamna biauriculata nigeriana nov. subsp. The locality of Sessao, which has been attributed to the Thanetian by means of the study of the fish, has furnished by screen-washing an interesting fauna wherein six new species are described: Raja Iouisi, Dasyatis sessaoensis, D. sudrei, D. russelli, Hypolophites thaleri and Ceratodus casieri. Comparison of these faunas with contemporary faunas of Africa has brought out a certain endemism in the Iullemmeden Basin during the late Cretaceous and the early Tertiary. 


  Article infos

Published in Vol. 05, Fasc. 5 (1972)

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Neue Beobachtungen zum Schädel-und Gebiss-Bau der Paulchoffatiidae (Multituberculata,Ober-Jura).
Gerhard Hahn
Keywords: Dentition; Paulchoffatiidae; Portugal; Skull structure; Upper Jurassic
 
  Abstract

    The ventral face of the Paulchoffatiinae skull (Multituberculata, Lower Kimmeridgian, Portugal) is new reconstructed. Some details hitherto unknown are added, as the presence of jugals, the structure of the palatine and the extension of the pterygoids. The situation of the m2/ is discussed. Kielanodon hopsoni n. g., n. sp. is erected, known by its upper p3-5/. From Guimarotodon leiriensis the mandible with its dentition is made known. New informations concerning the milk-dentition and the replacement of teeth are also added. 


  Article infos

Published in Vol. 17, Fasc. 4 (1987)

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A new rodent from Quaternary deposits of the Canary Islands and its relationships with Neogène and recent murids of Europe and Africa.
Rainer Hutterer, Nieves Lopez-Martinez and Jacques Michaux
Keywords: Canary Islands; Holocene; Island evolution; Muridae; PHYLOGENY; Rodents; Spain
 
  Abstract

    A peculiar new rodent, Malpaisomys insularis nov. gen., nov. sp., is described from subfossil deposits of the eastern Canary Islands. The species shows some highly specialized skull features although its molars exhibit a mixture of primitive and derived characters among which a partial stephanodonty is most notable. A comparison of the new rodent with several Miocene to Holocene Muridae shows that Malpaisomys possibly shares a common ancestor with Acomys and Uranomys


  Article infos

Published in Vol. 18, Fasc. 4 (1988)

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Rodent paleocommunities from the Oligocene of Ulantatal (Inner Mongolia, China)
Helder Gomes Rodrigues, Laurent Marivaux and Monique Vianey-Liaud
Keywords: late Paleogene; Mammalia; Mongolian Plateau; Rodentia; Systematics

doi: 10.18563/pv.38.1.e3
 
  Abstract

    The Oligocene deposits of the Ulantatal area in Inner Mongolia (China) contain among the richest mammalian faunas from Asia. To date, only some parts of the rodent faunas have been described. Here, we propose to review the rodent faunal lists for each site, including the description of a few new rodent specimens. We describe three additional rodent species: the Cylindrodontidae Anomoemys lohiculus, the Eomyidae Asianeomys sp., and the Dipodidae Litodonomys huangheensis. This study allows us to constrain the stratigraphic range of Anomoemys lohiculus, which ranged from the late Early Oligocene to the early Late Oligocene in this area. Asianeomys sp. and Litodonomys huangheensis are dated from the latest Oligocene. These Oligocene deposits consist now of more than 70 species of mammals if we include the fauna from Kekeamu. This latter corresponds to the basal part of the Ulantatal Formation and could be dated biochronologically from the earliest Oligocene. When compared to the faunas from the Valley of Lakes in Central Mongolia, the Ulantatal faunas present a great majority of rodents, and this difference can be partly explained by sampling and description biases regarding macro-mammals. This study also shows that variations existed between Inner and Central Mongolia, especially regarding the composition of the rodent paleocommunities. However, the assessment of their evolutionary history in this part of Asia with respect to the important climate and environment changes, require further precisions and more material than current data allow. 


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Published in Vol.38-1 (2014)

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A pangolin (Manidae, Pholidota, Mammalia) from the French Quercy phosphorites (Pech du Fraysse, Saint-Projet, Tarn-et-Garonne, late Oligocene, MP 28)
Jean-Yves Crochet, Lionel Hautier and Thomas Lehmann
Keywords: Oligocene; Pangolin; Pech du Fraysse; Quercy phosphorites

doi: 10.18563/pv.39.2.e4
 
  Abstract

    Pangolins have never shown a high taxic diversity and their fossil record is scarce. We report here the first discovery of a partial humerus from late Oligocene deposits in Pech du Fraysse (MP28, France). The new specimen from Pech du Fraysse is described and compared to various extant and extinct species of pangolins. It shows a suite of morphological features very similar to the humeri discovered in Saint-André (MP 26), Solnhofen (Burdigalien), and Saulcet (Aquitanian), attributed here to Necromanis franconica. The description of the specimen from Pech du Fraysse allowed us to discuss the systematics of Paleogene and Neogene pholidotans. The differences between PFY 4051 and N. franconica on the one side, and N. quercyi on the other side, might be sufficiently important to justify a generic distinction. A comparison with extant species showed that N. franconica was likely terrestrial and fossorial based on its humeral morphology. 



  Related dataset
  Article infos

Published in Vol.39-2 (2015)

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Acinoptèrygiens du Stéphanien de Montceau-les-Mines (Saône-et-Loire, France).
Daniel Heyler and Cécile Poplin
Keywords: Aeduelliforms; Biogeography; Palaeonisciforms; paramblypteriforms; Stephanien
 
  Abstract

    The study of new specimens from the Stephanian shales of Montceau-les-Mines confirms and enlarges the number of groups already known in this area. Among the Palaeonisciforms, “form A" is now known more completely, although no diagnosis or name can yet be given for it. “Form B" is redescribed and its relationships with “Elonichthys robisoni" are discussed. A palaeoniscid is recorded which resembles those from Bourbon l'Archambault. The paramblypteriforms occur rather frequently, but no genera can be determined. The aeduelliforms comprise some specimens close to Aeduella blainvíllei from Muse (Autun basin), and a new genus. Comparison of the latter with two fossils from Lally allows creation of two new species and a new family. This diversification of the aeduelliforms during this middle Stephanian leads to the hypothesis that the group originated at least as early the lower Stephanian. This material prooves again the characteristic endemism of this fauna, particularly of the aeduelliforms which are known only in the Massif Central where they diversified during the Permo-Carboniferous. Biogeographical consequences are discussed. 


  Article infos

Published in Vol. 13, Fasc. 3 (1983)

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First record of the family Protocetidae in the Lutetian of Senegal (West Africa)
Lionel Hautier, Raphaël Sarr, Fabrice Lihoreau, Rodolphe Tabuce and Pierre Marwan Hameh
Keywords: innominate; Lutetian; Protocetid; Senegal

doi: 10.18563/pv.38.2.e2
 
  Abstract

    The earliest cetaceans are found in the early Eocene of Indo-Pakistan. By the late middle to late Eocene, the group colonized most oceans of the planet. This late Eocene worldwide distribution clearly indicates that their dispersal took place during the middle Eocene (Lutetian). We report here the first discovery of a protocetid fossil from middle Eocene deposits of Senegal (West Africa). The Lutetian cetacean specimen from Senegal is a partial left innominate. Its overall form and proportions, particularly the well-formed lunate surface with a deep and narrow acetabular notch, and the complete absence of pachyostosis and osteosclerosis, mark it as a probable middle Eocene protocetid cetacean. Its size corresponds to the newly described Togocetus traversei from the Lutetian deposits of Togo. However, no innominate is known for the Togolese protocetid, which precludes any direct comparison between the two West African sites. The Senegalese innominate documents a new early occurrence of this marine group in West Africa and supports an early dispersal of these aquatic mammals by the middle Eocene.
      



  Related dataset
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Published in Vol.38-2 (2014)

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Les rongeurs de l'Oligocène inférieur d'Escamps
Monique Vianey-Liaud
Keywords: Escamps; Quercy phosphorites; Rodents; Theridomyidae
 
  Abstract

    La faune de Rongeurs d'Escamps (Lot) bien que relativement pauvre en espèces (dix) s'avère riche d'enseignement pour les Rongeurs de l'Oligocène inférieur d'Europe Occidentale. Cette periode semble caracterisée par une cladogenèse des Théridomyines. A Escamps, un nouveau genre (Patriotheridomys) est décrit ainsi qu'une nouvelle espèce de Theridomys. Avec Oltmamys platyceps, décrit ici plus complètement et désormais bien situé stratigraphiquement, les deux espèces précédentes constituent un ensemble original du Sud de la France. A la même époque, en Angleterre, Allemagne et Espagne, des espèces «régionales» de Théridomyinés se dersifient.  A côté de ces formes qui ne semblent pas franchir la «Grande Coupure» sont représentées deux lignées d'Issiodoromyinés (Elfomys sp et Pseudoltmomys cuvieri), une de Théridomyiné (T. (Blainvillimys) rotundidens) ainsi qu'un Gliridé, Gliravus priscus (que l'on différencie nettement de la deuxième lignée des Gliravus oligocènes : G.  meridionalis -> G. majori). On retrouve ces formes dans les gisements plus récents du niveau de Hoogbutsel où elles sont à peine plus évoluées. Le fait que les degrés évolutifs de ces lignées soient très proches laisse supposer que le laps de temps séparant les niveaux d'Ecamps et Hoogbutsel fut relativement court. 


  Article infos

Published in Vol. 06, Fasc. 3-4 (1975)

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A primitive Emballonurid bat (Chiroptera, Mammalia) from the Earliest Eocene of England
Jerry J. Hooker
Keywords: bats; Early Eocene; Emballonuridae; Origins; PHYLOGENY
 
  Abstract

    A new genus, Eppsillycteris, is erected for Adapisorex? allglicus COOPER, 1932, from the earliest Eocene Blackheath Beds of Abbey Wood, London, England. Various derived character states indicate that it belongs to the order Chiroptera (bats) rather than to the extinct "insectivore" family Adapisoricidae. Other derived character states are shared with fossil and modern members of the family Emballonuridae. Placement of the new genus in this family extends the record of the Emballonuridae back in time by about 10 million years. It is the earliest record of a modern bat family and one of the earliest bats. This implies that the differentiation of at least some modern bat families took place in the Palaeocene, where no authenticated records of bats yet exist. The primitive characters of the earliest bats make the family Nyctitheriidae an unlikely stem group for the order Chiroptera. A tentative plausible alternative exists in some unnamed upper molars from the Palaeocene of Walbeck, Germany. Wyollycteris chalix, described as a bat from the Late Palaeocene of Wyoming, U,S.A., fits better in the family Nyctitheriidae. 


  Article infos

Published in Vol. 25, Fasc. 2-4 (1996)

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Schmelzmikrostruktur in den inzisiven alt-und neuweltlicher histricognather nagetiere
Thomas Martin
Keywords: Africa; Caviomorpha; Ctenodactyloidea; Deseadan; Enamel microstructure; Hunter-Schreger bands; Hystricognathi; Incisors; Ischyromyoidea; multiserial; Paleobiogeography; pauciserial; Phiomorpha; Rodentia; South America
 
  Abstract

    Enamel microstructure in the incisors of Old- and New World hystricognath rodents:

    The incisor enamel microstructure in more than 100 genera of fossil and Recent hystricognath and sciurognath rodents was studied. A multiserial schmelzmuster is present in the Hystricognathi, the Ctenodactylidae, advanced Chapattimyidae, and in Pedetes. A redefinition of pauciserial and multiserial HSB is given that makes the two enamel types unambiguously distinguishable which apparently represent well defined evolutionary levels. In the pauciserial Schmelzmuster the IPM is thicker than in the multiserial one. In pauciserial HSB the IPM always surrounds each prism, and the crystallites of the IPM run parallel to prism direction; transition zones between HSB are lacking; the inclination of the HSB is normally very low and the prism cross sections are not flattened but somewhat irregular. The number of prisms per HSB is no good distinctive character for pauciserial and multiserial HSB, since there exists a wide overlap. The pauciserial schmelzmuster is primitive, the multiseiial derived because: 1. the pauciseiial schmelzmuster appears earlier in the fossil record in the most primitive rodents (Paramyids s.l. and Ctenodactyloids); 2. the Eocene Ctenodactyloidea show pauciserial HSB but the Oligocene and younger ones are characterized by multiserial HSB; 3. in the outgroup comparison, the Eurymylidae (Mixodontia) show pauciserial HSB; 4. biomechanically, multiserial HSB strenghten the enamel better than pauciserial HSB, since their IPM runs nearly always in an angle of 45° or more to the prisms.

    In multiseríal HSB three subtypes can be distinguished which are differentiated by the IPM orientation. Primitive is a (rarely strict) parallel or acute angular, anastomozing IPM, and derived is an interrow sheet-like ("plattenartige") IPM. This evolutionary polarity is indicated by enamel evolution in the Ctenodactylidae which show an acute angular IPM in the Oligocene and a rectangular interrow sheet-like IPM since the Miocene. Among the Caviomorpha a rectangular interrow sheet-like IPM is restricted to the Octodontoidea; therefore they must be considered derived in terms of their enamel structure. The first multiserial HSB in rodent incisors appear in phiomyids or chapatrimyids from the Upper Eocene of Algeria. The IPM is acute angular and anastomozing. The worldwide next younger multiserial HSB are found in Lower Oligocene phiomyids of Fayum, Egypt There already a rectangular interrow sheet like IPM is present (in Metaphiomys) besides the acute angular anastomozing IPM.

    The first Caviomorpha from the Deseadan (Oligocene-Miocene) likewise show already acute angular anastomozing IPM (e.g. Scozamys) and rectangular interrow sheet-like IPM (Platypittamys). Therefore the first Caviomorpha cannot be positioned close to a transition from pauciserial to multiserial HSB. In none of the potential caviomorph ancestors from southern North America multiserial HSB or transitional stage between pauciserial and multiserial HSB could be found. The similarities between the enamel types of the Fayum rodents and the rodents from the Deseadan of South America make a derivation of the Caviomorpha from Paleogene North African phiomorph rodents or their direct ancestors most probable. This supports at the same time a descent of the platyrrhine Primates from North African anthropoids.
      


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Published in Vol. 21, Ext (1992)

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Révision systématique des Anchilophini (Palaeotheriidae, Perissodactyla, Mammalia).
Jean-Albert Remy
Keywords: Anchilophus; Eocene; new genus; new species; Palaeotheriidae; Paranchilophus; Perissodactyla; Systematics

doi: 10.18563/pv.37.1-3.1-165
 
  Abstract

    The knowledge of the Anchilophini has been lately renewed by the discovery of a rather large amount of new material still largely unpublished. This new material offers the opportunity of a systematic revision of this tribe gathering those of European Eocene Equoidea which bear no mesostyle on upper check teeth and display a heavy trend to the molarization of premolars.

    A cladistic analysis has made out two genera, Anchilophus (Paranchilophus included as a subgenus), characterized by a marked lophodonty and the transverse narrowness of the cheek teeth, a rather high hypsodonty, the frequent occurrence of "crochets" and "anticrochets" on the superior ones, and a rather weak molarization of the premolars, opposite to Metanchilophus n. gen. whose cheek teeth are more transversally elongated, less high, less lophodont, with cusps better distinct, enamel thicker and premolars more molarized on the whole.

    Three species of Anchilophus are recognized, A. desmaresti, type species of the genus, A. (Paranchilophus) remyi and A. (Paranchilophus) jeanteli n. sp.

    The genus Metanchilophus is more diversified with the species dumasi, radegondensis, gaudini (whose a new sub-species M. g. fontensis is defined), depereli, castrensis n. sp. and chaubeti n. sp.

    The skull anatomy has been moreover described with several taxa; it brings to light (for all that one can generalize) that Anchilophini were light animals with a slender and elongated snout, a thin zygomatic arch, a rather developed encephalon with an advanced gyrencephaly.

    The structure of the nasal opening together with the occurrence of epitympanic sinuses and the molarizing process of the premolars corroborate the attribution of this tribe to the family PalaeotheIiidae. 


  Article infos

Published in Vol. 37, Fasc. 1-3 (2012)

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