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Lissamphibians from Dams (Quercy, SW France): Taxonomic identification and evolution across the Eocene-Oligocene transition
Published online: 25/06/2025
Keywords:
Eocene-Oligocene; Grande Coupure; Lissamphibia; Quercy Phosphorites
https://doi.org/10.18563/pv.48.1.e3
Abstract
The locality of Dams (Quercy, southwestern France) has yielded two fossil assemblages, one from the late Eocene and another from the early Oligocene, making it one of the few localities with infillings across the Eocene-Oligocene transition. At least 24 taxa (13 mammals, 11 snakes) have been identified in this locality. Study of the lissamphibian remains from Dams yields an Eocene and an Oligocene assemblage, with a total of eight taxa. The Eocene assemblage includes two unnamed salamandrine species, one unnamed pelobatid species and one pyxicephalid species (Thaumastosaurus). The Oligocene assemblage includes two unnamed pleurodeline species, one salamandrine species (Salamandra sansaniensis) and an unnamed pelobatid species. Among the eight taxa from Dams, one Eocene salamandrine and one Oligocene pleurodeline are identified for the first time in the Quercy. A review of the lissamphibians from the Quercy area identifies eleven taxa for the Late Eocene (MP19) and eight taxa for Early Oligocene (MP22), with a major turnover at the Eocene-Oligocene transition. This turnover occurs in a time of major climatic changes, with a significant decrease in temperature and precipitation and concurrent increase in seasonality in Europe, likely affecting specialized taxa.
PV article infos
Published in 48-1 (2025)
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Acinoptèrygiens du Stéphanien de Montceau-les-Mines (Saône-et-Loire, France).
Published online: 30/09/1983
Keywords:
Aeduelliforms; Biogeography; Palaeonisciforms; paramblypteriforms; Stephanien
https://doi.org/10.18563/pv.13.3.33-50
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.
PV article infos
Published in Vol. 13, Fasc. 3 (1983)
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Stratigraphy and Oligocene-Miocene mammalian biochronology of the Aktau Moutains, Dzhungarian Alatau Range, Kazakhstan
Published online: 16/12/1996
Keywords:
Dzhungarian Alatau; Kazakhstan; Lithologic correlation; Mammalian biochronology; Miocene; Oligocene; Stratigraphy
Abstract
Stratigraphic studies in the Aktau Mountains bordering the Dzhungarian Alatau Range in southeastern Kazakhstan have included mapping of Tertiary lithostratigraphic units, documentation of fossiliferous deposits, correlation of sections, etc. These investigations have led in turn to revised interpretation of the Tertiary geology of the area. The Tertiary sequence in the Aktau Mountains is represented by three lithostratigraphic units (in ascending order): (1) the middle Eocene Akbulak Formation; (2) the Oligocene Aktau Formation with a lower member including white quartz sands that contain fossil mammals, and an upper member including red-colored clays and sandstones, brick red clays, an anhydrite and gypsum clayey horizon, and bright brown-red clays; and (3) the upper Oligocene-Miocene Chul'adyr Formation with a lower member of greenish and yellowish conglomerates and gritstones, a middle member including grayish and yellowish sands and gritstones, and an upper member including brown and red clays and carbonate- and anhydrite-rich clays. The Aktau and Chul”adyr Formations represent separate cycles of sedimentation. Mammalian biostratigraphy and biochronology of the three vertebrate faunas in Aktau Mountains are reviewed. The mammalian fauna from white sands of the lower Aktau Formation is small but includes Ardynia and is thought to be early Oligocene in age. The mammalian fauna from conglomerates and gritstones of the lower member of the Chul”adyr Formation is also small but includes Paraceratherium and is thought to be late Oligocene in age. The mammalian fauna from sands of the middle member of the Chul'adyr Formation is extensive, with micro- and macrofauna attributed to Neogene mammal zones MN4 to MN 6, indicating a latest early Miocene to earliest middle Miocene age (Orleanian-Astaracian). Most genera of middle Chul”adyr mammals are known from the middle Miocene Shanwang faunas of China and from the Castelnau-d”Arbieu faunal assemblage (MN4-MN6) of southwestern France.
PV article infos
Published in Vol. 25, Fasc. 2-4 (1996)
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Les Paramyidae (Rodentia) de l'Eocène inférieur du bassin de Paris.
Published online: 15/07/1968
Keywords:
Ailuraviinae; Eocene; Paramyinae; Rodents
https://doi.org/10.18563/pv.1.4.135-193
Abstract
The exploitation of new early Eocene localities in the Paris Basin has resulted in the collecting of numerous mammalian remains, among which are about 300 isolated teeth representing the rodents. They belong, for the most part, to the paramyid group. Only the latest level of the early Eocene has yielded rodents belonging to the pseudosciurid group. The paramyids, the object of this study, are represented by at least 5 genera and 10 species; they are distributed among 4 clearly dilferentiated subfamilies : Paramyinae Simpson 1945, Pseudoparamyinae Michaux 1964, Ailuraviínae n. subf., Microparamyinae Wood1962.
It results from this study that the principal types of rodents in the middle and late Eocene of Europe are clearly related to the forms described here: Plesiarctomys Bravard 1850 is related to Pseudoparamys Michaux 1964, Ailuravus Rütimeyer1891 to Meldimys n. gen., Gliravus hammeli Thaler 1966 to Microparamys nanus (Theilard1927), and some Masillamys Tobien 1954 to Microparamys russelli Michaux 1964 and to M. sp. 1. Gliravus and Masillamys are the oldest representatives of the Gliridae and the Pseudosciurídae, respectively, families which will progressively replace the Paramyidae in the course of the middle and late Eocene.
Two stages can be recognized in the history of te European Paramyidae fauna during the course of the early Eocene: the older is characterized by the Mutigny fauna, the younger by the Cuis fauna.
The Mutigny fauna appears already rather diversified and does not completely correspond, point by point, to the homologous fauna of North America. A geographic differentiation seems to have been manifested rapidly, unless the fauna established in Europe was already a little different from that which established itself in North America.
PV article infos
Published in Vol. 01, Fasc. 4 (1968)
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Ostéologie de la tête de Richardus excavans Lavocat,1988
Published online: 30/10/1989
Keywords:
Africa; anatomy; Bathyergidae; Miocene; Rodents
https://doi.org/10.18563/pv.19.2.73-80
Abstract
Remarkable association of a small infraorbital foramen, similar to that in recent Heterocephalus, and of a strong muscular print on the dorsal anterior part of the zygomatic plate and on the premaxillary. Several anatomical structures to be compared with those of Heterocephalus suggest relationships with this genus. Richardus supports the ancestrality of the hystricomorph character in the bathyergids
PV article infos
Published in Vol. 19, Fasc. 2 (1989)
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Octodontid-like Echimyidae (Rodentia) : an upper Miocene episode in the radiation of the family
Published online: 20/05/1994
Keywords:
Argentina; Echimyidae; Miocene; New taxa; Rodentia; South America
Abstract
Reigechimys octodontiformis gen. et sp. novo and R. plesiodon sp. novo are described. They represent the frrst record of the family Echimyidae for the Cerro Azul Formation (Huayquerian Age, Late Upper Miocene) at La Pampa Province, central Argentina. Both species have hypsodont cheek teeth with an eight-shaped occlusal design. This dental morphology represents a noticeable case of convergence to octodontids and indicates that these echimyids inhabited open environments.
PV article infos
Published in Vol. 23, Fasc. 1-4 (1994)
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Preliminary report on the fishes (Chondrichthyes & Teleostei) from the lower Oligocene (Rupelian) Red Bluff Clay at site AMo-9, Monroe County, Alabama, USA
Published online: 26/06/2024
Keywords:
Batomorphii; Elasmobranchii; Galeomorphi; Gulf Coastal Plain; Vicksburg Group
https://doi.org/10.18563/pv.47.2.e2
Abstract
Herein we describe a small but relatively diverse assemblage of fossil fishes derived from the lower Oligocene (Rupelian) Red Bluff Clay at site AMo-9 in Monroe County, Alabama, USA. Identified amongst the remains are 15 unequivocal taxa representing 11 families within five orders, and one additional taxon represents an unknown order and family. Taxa identified include Eostegostoma sp., Otodus (Carcharocles) sp., Mitsukurinidae/Carchariidae indet., Macrorhizodus praecursor, Galeorhinus sp., Negaprion gilmorei, Physogaleus sp., “Sphyrna” sp., Galeocerdo sp., cf. “Aetobatus” sp., Sphyraena sp., Xiphiorhynchus kimblalocki, Xiphiorhynchus sp., Cylindracanthus ornatus, and C. rectus. Several additional fossils could not be identified beyond Lamniformes, Carcharhiniformes, and Teleostei, but they likely belong to one of the identified taxa within this paleofauna. All of the fishes previously reported from the Red Bluff Clay within the entirety of the Gulf Coastal Plain of the USA are otolith-based, and each of the 15 unequivocal taxa reported herein are important new records for this lithostratigraphic unit. In particular, the Eostegostoma sp. and Xiphiorhynchus spp. specimens represent the first occurrences of these taxa in Alabama. The specimens of C. ornatus, Eostegostoma sp., and X. kimblalocki are stratigraphic and temporal range extensions from the middle and late Eocene into the Rupelian Stage of the Oligocene. Other described taxa may represent transitional forms between those described from the late Eocene and late Oligocene within the region. This study provides a tantalizing preliminary view into faunal transitions that occurred amongst marine fishes across the Eocene/Oligocene boundary within the Gulf Coastal Plain of the USA.
PV article infos
Published in 47-2 (2024)
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Nouveaux Mammifères Eocènes du Sahara Occidental
Published online: 01/11/1979
Keywords:
Eocene; Mammals; Occidental Sahara
https://doi.org/10.18563/pv.9.3.83-115
Abstract
The fossil mammals collected from the Eocene of Hammada du Dra (northwest Sahara. Algeria) and two fragmentary teeth from the Lutetian of M'Bodione Dadere (Senegal) are described.
The fossils from the northwest Sahara come from a lacustrian deposit dated by charophytes (Raskyella aff. pecki, Raskyella n. sp.. Maedleriella lavocati, Maedleriella sp. et ? Peckichara sp.) as Middle Eocene or perhaps Lower Eocene (Gevin, Feist and Mongereau, 1974). Several hyracoids (3 or 4) identified from this formation extends the age of the family Pliohyracidae Osborn in Africa. Three forms appear to belong in the genera Megalohyrax, Titanohyrax and perhaps Bunohyrax which have been know until now only from the lower Oligocene of the Fayum (M. gevini n. sp. ; T. mongereaui n. sp.. ? Bunohyrax or Megalohyrax indet.). Another hyracoidof small size is referred to a new genus, Microhyrax (M. lavocati n. sp.).
Helioseus insolitus n. g. n. sp. is described without ordinal assignment. Azibius (Sudre, 1975) which has been the subject of questions and interpretations is reviewed.
Only one tooth from the Lutetian of M'Bodione Dadere is complete enough to interpret. lt probably belongs to a condylarth and demonstrates for the first time, the presence of the order in Africa. The second tooth is too fragmentary for comment.
In conclusion., the paleobiogeographic role of Africa at the end of the cretaceous and the beginning of the Cenozoic is discussed.
PV article infos
Published in Vol. 09, Fasc. 3 (1979)
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Les rongeurs de l'Eocène d'Afrique Nord-Occidentale [Glib Zegdou ( Algérie) et Chambi (Tunisie)] et l'origine des anomaluridae.
Published online: 20/05/1994
Keywords:
Africa; Eocene; New taxa; Paleobiogeography; PHYLOGENY; Rodents
Abstract
This paper is about the oldest African rodents faunas, from the late Early Eocene, or early Middle Eocene, Glib Zegdou (Algeria) and Chambi (Tunisia) localities. Five species are described and figured, belonging to a new family here created, the Zegdoumyidae.
This family is compared to the Early and Middle Eocene rodents families from Asia, Europe and North America (Chapattimyidae, Yuomyidae, Gliridae, Theridomyidae, lschyromyidae and Sciuravidae), as well as to those known from the Late Eocene African locality Bir El Ater (Anomaluridae and Phiomyidae).
On the one hand, it seems clear that the African endemic Anomaluridae arise from the Zegdoumyidae. On the other hand, the lschyromyidae, or primitive Sciuravidae, may be the most reliable ancestral groups for the Zegdoumyidae. Thus, this new family can be considered as the sister group for the American Sciuravidae on the one hand, and for the European Gliridae on the other hand.
The biogeographical consequences of these phylogenetic hypotheses are discussed. A new phase of communication between Europe and North Africa is inferred, during the Early Eocene. It has been followed by a short period of endemism, allowing the adaptive radiation for the Zegdoumyidae, preceding the immigration of the Phiomyidae, during the Late Eocene, probably from Asian relatives.
PV article infos
Published in Vol. 23, Fasc. 1-4 (1994)
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Le genre Plagiolophus (Palaeotheriidae, Perissodactyla, Mammalia): révision systématique, morphologie et histologie dentaires, anatomie crânienne, essai d'interprétation fonctionnelle
Published online: 15/12/2004
Keywords:
New taxa; Paléogène; perissodactyls; skull anatomy; tooth histology
Abstract
The genus Plagiolophus is documented, almost solely in Western Europe, from the middle Eocene up to the mid Oligocene (MP 12 to MP 25), i.e. more than for 15 MY. Seventeen species are now recorded whose two of them are new, P. ringeadei nov. sp. and P. mamertensis nov. sp. Some anatomical variations and the deflection of certain evolutionary trends justify the distinction of three subgenera, Paloplotherium, Fraasiolophus nov. and Plagiolophus s.s. The genus displays a wide range in size and weight (between 10 and 150 kg). The detailed description of the skull of several species is here given for the first time. Despite important evolutionary drifts during this long time span, the dentition shows a great structural homogeneity, which renders difficult the determination of fragmentary specimens or isolated teeth. It is characterized by a great heterodonty; premolars are little molarized and present a certain regression through time with paradoxically some progress in the molarization. The hypsodonty increases: the first Plagiolophus are hardly less brachyodont than Propalaeotherium, and the last ones are nearly as hypsodont as Merychippus from the early Miocene. The upper molars change from a wide crown pattern, with an open occlusal surface, lightly oblique transverse lophs and rounded internal cusps, to a narrower pattern, with a frontally constricted occlusal surface and internal lophs aligned parallel to the ectoloph. The M3/3 become always longer.
The dental enamel displays horizontal Schreger-bands with imprecise limits occupying only the middle part of the enamel layer. The dentine is remarkable by its high rate of pericanalicular dentine. The crown cementum, lacking in earlier forms, increases to the point where it fills the occlusal valleys of the teeth.
The masticatory musculature shows a increasing prominence of the temporal, with probably an important role devoted to the pterygoid muscles in lateral movements related to a two-phase type of chewing.
The evolution of the dentition, of the masticatory musculature and of the repartition of masticatory forces indicate that the Plagiolophus have known different diets through their long evolutionary history; at first browsers they became mixed feeders and finally grazers. Their relatively long neck allowed these animals to reach different vegetal layers. The strength of the nuchal crests also suggests that they were able to have strong backwards movements of the head to pull up their food.
This evolution of diet seems related to the slow degradation of environmental conditions attested during this period in western Europe, with the generalization of more open landscapes, increasing aridity and more marked seasons.
Besides, a remodeling of the face is ontogenetically and along time observed, in relation with the evolution of the masticatory apparatus and especially with that of the mandibular lever arm. The postcanine diastemata become longer in the course of evolution; the free extremities of the nasals are always relatively long which contradicts the hypothesis according to which Paloplotherium may have had a trunk. At last the lineage Fraasiolophus can be distinguished by the presence of a deep malar fossa, probably related to a strong development of the maxillo-labialis superior muscle.
The orbit is always large and tends to increase in size, which indicates a good development of the vision and its increasing role in the life relations. A peculiar type of epitympanic sinus could have been used as a resonance chamber insuring a certain amplification of sounds before their transmission to the eardrum. The endocranial cast reveals a relatively large brain with an advanced degree of gyrencephaly. Beside the role eventually played in food research and social relations, these neurophysiological abilities, also related to an advance in cursorial fitness, could have contributed to the survival of these animals facing the predation pressure of the first fissipede carnivores and the competition with new immigrant herbivores after the "Grande Coupure". On the basis of some shared apomorphies with the Pachynolophinae, which prevent from considering the latter as Equidae (molarization of the premolars, reduction of the premaxilla dorsal apophysis, peculiar epitympanic sinus, splitting of the jugular process), the hypothesis of an autochthonous origin of Plagiolophus issued from a form near Propalaeotherium, is once again proposed and discussed. Finally, intra-generic relationships are taken into consideration.
PV article infos
Published in Vol. 33, Fasc. 1-4 (2004)
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Anatomie du membre antérieur chez un chiroptère Molossidé (Tadarida sp.) du Stampien de Cereste (Alpes-de-Haute-Provence).
Published online: 01/01/1971
Keywords:
Chiroptera; Molossidae; Oligocene
https://doi.org/10.18563/pv.4.1.1-38
Abstract
The present study describes in detail the anterior limb osteology of a molossid chiropteran of the genus Tadarida, from Céreste, a Stampian locality in the Apt-Forcalquier Oligocene basin already known for its fishes, plants and insects.
A comparision with the Miocene forms T. srehlini from Saint-Géraud localities and T. sp. from Württemberg, also with the recent forms T. teniotis and Eumops perotis, does not show any clear morphological differences between the Tertiary and Recent Tadarida, indicating a rather noticeable anatomical stability, not exceptionnal indeed among Chiropterans. The Céreste fossil exhibits however slightly primitive wing proportions if compared to the Saint Gérand Aquitanian species.
Several remarks deal with the peculiar relationships between the ecology of the molossids and their kind of fossilisation, frequently associated with sedimentary facies of the lacustrine type.
PV article infos
Published in Vol. 04, Fasc. 1 (1971)
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Compléments sur les Chiroptères de l'Eocène moyen d'Europe. Les genres Palaeochiropteryx et Cecilionycteris.
Published online: 01/10/1980
Keywords:
Chiroptera; Geiseltal; Messel; Middle Eocene
https://doi.org/10.18563/pv.9.ext.91-126
Abstract
New dental and skeletal material referable to Palaeochiropteryx tupaiodon from the Middle Eocene locality of
Messel (G.F.R.) is studied, which provides additions to the previously gained knowledge of this european genus. Dental specimens from Geiseltal (G.D.R.), also of Middle Eocene age, allow us to analyze Cecilionycteria prisca. Some of these are separated to establish a new genus, Matthesia, and two new species, M. germanica and M. ? insolita.
PV article infos
Published in Vol. 9, Ext (1980)
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Le genre Mesembriacerus (Bovidae, Artiodactyla, Mammalia) : un Oviboviné primitif du Vallésien (Miocène supérieur) de Macédoine (Grèce)
Published online: 15/12/1984
Keywords:
Bovidae; Cladistics; Late Miocene; Ovibovinae; Vallesian
https://doi.org/10.18563/pv.14.4.201-223
Abstract
The bovid Mesembriacerus melentisi, the numerous skulls, teeth and limb bones of which are described from the locality Ravin de la Pluie (Macedonia, Greece), bears some features which allow us to put it in the tribe ovibovini (Ovibovinae) with several other Miocene genera and the Recent one Ovibos. A cladogram gives the phyletic relationships within this tribe. It shows that Mesembriacerus which is one of the oldest genera, is also the most primitive. The limb bones are as elongated as those of Recent cursorial bovids and they show, as does the bulk of the fauna, an open environment for the locality.
PV article infos
Published in Vol. 14, Fasc. 4 (1984)
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Deux nouveaux primates dans l'Oligocène inférieur de Taqah (Sultanat d'Oman): premiers Adapiformes (?Anchomomyini) de la péninsule arabique?
Published online: 15/11/1993
Keywords:
Adapids; Afro-Arabian plate; Early Oligocene; New taxa; Primates; Trans-Tethyan dispersals
Abstract
Two new species, Omanodon minor n. g., n. sp. and Shizarodon dhofarensis n. g., n. sp., known from fifteen isolated teeth, are described here as the first adapiform primates (?Anchomomyini) recognizable to date in the Taqah material (early Oligocene of Sultanate of Oman).
Omanodon minor n. g., n. sp. displays special morphological similarity to the adapid tribe Anchomomyini from the Eocene of Europe, and especially to the Anchomomys lineage. Resemblances with the extant lemurifonn Microcebus are also noticeable and could be regarded as supporting Schwartz & Tattersall (1983) hypothesis of special relationships between the anchomomyine adapids and the cheirogaleid lemuriformes. However, these morphological affmities can be interpreted, altematively, as the results of parallelisms: important differences in upper molars indicate that the resemblances of cheirogaleids and Omanodon minor n. g., n. sp. are indeed probably due to parallelisms. Phyletic relationship of O. minor n. g., n. sp. to Anchomomyini is finally the most likely hypothesis.
Shizarodon dhofarensis n. g., n. sp., although much more poorly known, is closely related to Omanodon minor n. g., n. sp., at least at a familial level. The general morphology of this species suggests
also a close link with adapid Anchomomyini, although precise relationships within this tribe remain obscure. Interesting resemblances of Shizarodon dhofarensis n. g., n. sp. to Djebelemur martinezi lower molars (early Eocene of Tunisia) are also noticeable. These resemblances are even stronger than those betwen Omanodon minor and Djebelemur martinezi. However the very bunodont upper molars referred to D. martinezi are unusual for adapids, and there are moreover some notable differences in their lower molars. Thus resemblances in Djebelemur and Shizarodon are probably due to paralellisms.
Because of the fragmentary nature of the material and of possible parallelisms, the systematic position of Omanodon and Shizarodon within adapiformes cannot however yet be established definitively.
PV article infos
Published in Vol. 22, Fasc. 4 (1993)
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Analyse d'ouvrage: Jean-Claude Rage, Handbuch der Paläeoherpetologie Teil 11: Serpentes
Published online: 15/11/1984
Keywords:
Book review
https://doi.org/10.18563/pv.14.3.199
Abstract
Le volume 11 du «Handbuch der Paläeoherpetologie», consacré aux «Serpellles» et redigé par Jean-Claude Rage, apporte une remarquable information sur ce groupe particulier de reptiles dont on ne pouvait guere se faire une idée très précise à partir, par exemple, des seuls chapitres des traités classiques de Paléontologie et de Zoologie.
PV article infos
Published in Vol. 14, Fasc. 3 (1984)
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L'occlusion dentaire chez Peradectes, Amphiperatherium et Peratherium, Marsupiaux du tertiaire d'Europe.
Published online: 01/10/1980
Keywords:
Didelphidae; Eocene; Mastication; Oligocene; Wear facets
https://doi.org/10.18563/pv.9.ext.79-89
Abstract
The general principles guiding the study of wear facets which develop during mastication in mammals possessing tribosphenic molars are named. The application of this method of study to the molars of European Tertiary Didelphidae shows that the lineage of this family as represented by the species Peratherium cuvieri (Upper Eocene), P. elegans (Lower-middle Oligocene) and P. antiquum (Upper Oligocene) has propessively evolved toward a more carnivorous diet.
PV article infos
Published in Vol. 9, Ext (1980)
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Discovery of the most ancient Notidanodon tooth (Neoselachii: Hexanchiformes) in the Late Jurassic of New Zealand. New considerations on the systematics and range of the genus
Published online: 21/09/2018
Keywords:
Chondrichthyes; Hexanchiformes; new genus; New Zealand; Tithonian
https://doi.org/10.18563/pv.42.1.e1
Abstract
This paper describes the first hexanchid tooth from the Tithonian (Late Jurassic) of New Zealand. For the moment, this tooth represents the earliest representative of the fossil genus Notidanodon in the world and one of the most ancient neoselachians in the Southern Hemisphere. Despite the perfect state of preservation of the unique tooth, the species is left in open nomenclature, pending the discovery of additional specimens. Few nominal species have been assigned to the genus Notidanodon. Four from Cretaceous deposits: N. antarcti Grande & Chatterjee, 1987, Notidanodon dentatus (Woodward, 1886), Notidanodon lanceolatus (Woodward, 1886), Notidanodon pectinatus (Agassiz, 1843) and only two from Paleocene: Notidanodon brotzeni Siverson, 1995, and Notidanodon loozi (Vincent, 1876). Considering the important morphological variations observed between some of these species, it seems obvious that the genus Notidanodon is not monophyletic and will need a revision in the future.
PV article infos
Published in Vol 42-1 (2019)
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Additions to the elasmobranch assemblage from the Bandah Formation (middle Eocene, Bartonian), Jaisalmer District, Rajasthan, India, and the palaeobiogeographic implications of the fauna
Published online: 23/06/2021
Keywords:
Chondrichthyes; Elasmobranchii; Indian Ocean; Palaeogene; South Asia
https://doi.org/10.18563/pv.44.2.e1
Abstract
Isolated elasmobranch teeth (sharks and rays) from the middle Eocene (Bartonian) Bandah Formation in the Jaisalmer District of Rajasthan, India are described. The remains improve our knowledge of the environment represented by this lithostratigraphic unit and the ecology preserved therein. Seventeen unequivocal taxa were identified, including Nebrius sp., Striatolamia aff. S. macrota, Brachycarcharias atlasi, B. lerichei, cf. Jaekelotodus sp., Carcharhinus mancinae, Rhizoprionodon sp., Physogaleus sp., Galeocerdo clarkensis, G. eaglesomei, Odontorhytis aff. O. pappenheimi, “Rhinobatos” sp., “Dasyatis” sp., Coupatezia sp., “Aetomylaeus” sp., “Rhinoptera” sp., and Ouledia aff. O. lacuna. Of these, “Aetomylaeus” sp., B. atlasi, C. mancinae, G. clarkensis, G. eaglesomei, cf. Jaekelotodus sp., Nebrius sp., Odontorhytis aff. O. pappenheimi, Ouledia aff. O. lacuna, and “Rhinoptera” sp. are reported from the middle Eocene of India for the first time. The Bandah Formation elasmobranch palaeofauna has close affinities to the Palaeocene-Eocene Tethyan/Paratethyan faunas of Africa, Madagascar, Asia, and Europe, and some taxa indicate a western hemisphere influence from North America. The Bandah Formation palaeofauna indicates that deposition occurred in a moderately shallow marine environment. The Bartonian age is primarily based on foraminifera but is corroborated by the presence of elasmobranch taxa that also occur in contemporaneous deposits elsewhere. The marine regression started during the early Palaeogene, and our study indicates that the sea completely withdrew from the Jaisalmer Basin after the deposition of the Bandah Formation. This event may have been synchronous with the middle Eocene uplift of the Himalayan-Tibetan Plateau.
PV article infos
Published in 44-2 (2021)
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Pairomys et Ectropomys : la fin d'une ambiguïté ; mise au point sur les Oltinomyinae et Remyinae (Rodenia, Theridomyidae).
Published online: 20/05/1994
Keywords:
PHYLOGENY; taxonomy; Theridomyidae; Upper Eocene
Abstract
The description of new material of the Upper Eoœne of France, Southem Germany and Spain together with the restudy of the material described by Thaler (1966b) as Pairomys allows to confirm the validity of the genus Ectropomys up to know controversally discussed. As a consequence the subfamily Remyinae and Oltinomyinae can be defined precisely. The study of the dental characters shows that the Remyinae in fact belong to the Theridomyidae and represent a derived evolutionary unit within this family. The Oltinomyinae together with the Theridomyinae and Issiodoromyinae very probably form a monophyletic unit.
PV article infos
Published in Vol. 23, Fasc. 1-4 (1994)
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Agriotherium intermedium (Stach 1957) from a Pliocene fissure filling of Xiaoxian County (Anhuei Province, China) and the phylogenetic position of the genus.
Published online: 30/09/1983
Keywords:
Carnivora; China; PHYLOGENY; Pliocene; skull anatomy; Ursidae
https://doi.org/10.18563/pv.13.3.65-81
Abstract
A fragmentary mandible and maxilla of a small sized Agriotherium of a young individual discovered from a Pliocene fissure filling in Xiaoxian county (Anhuei Province, China) are described. Judging from the morphology of the dentition and its dimensions the new material can be identified as Agriotherium inlermedium (STACH l957). Hendey's proposition (1980) that the Agriotherium species are derived from Indarctos is reconsídered on the basis of the new documents. As a result of a more general phylogenetic discussion it can be stated, that: 1. the supposed size increase as well as other trends, leading from Indarctos to Agriotherium are untenable ; 2. there are no positive indications to assume a phylogenetic transition of these two genera. 3. there are no real arguments in favor of an adaptational reversal in the evolution of Agriotherium. Hence, many features of that genus supposed by Hendey to be derived are plesiomorphic ; 4. regardless of the previous points it is methodologícally impossible to establish direct ancestor - descendant relationships between Indarctos and Agriotherium species, as Hendey did. Based on the data available and especially on the characters of the new material from China it is more likely that Agriotherium and Indarctos are two genera which developed independently. While advanced Agriotherium species, e.g. A. africanum, resemble in some respects Indarctos by adaptational analogies, more primitive species, e.g. Agriotherium intermedium, are quite dissimilar to lndarctos. While Indarctos might be derived from an Ursavus like forerunner, Agriotherium has its roots more likely somewhere in between Ursavus and the Hemicyon-group.
PV article infos
Published in Vol. 13, Fasc. 3 (1983)
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