Current issue


2025-12
48-2
<< prev. next >>

Print ISSN: 0031-0247
Online ISSN:
2274-0333
Frequency: biannual

Article Management

You must log in to submit or manage articles.

You do not have an account yet ? Sign up.

Most downloaded articles (last week)


Page 13 of 19, showing 20 record(s) out of 365 total

A New caseid Synapsid from the Permian (Guadalupian) of the Lodève basin (Occitanie, France)
 
Ralf Werneburg Logo, Frederik . Spindler Logo, Jocelyn . Falconnet Logo, Jean-Sebastien Steyer Logo, Monique Vianey-Liaud Logo and Jörg-W. Schneider
Published online: 18/07/2022

Keywords: ; Caseidae; France; Guadalupian; semi-aquatic lifestyle

https://doi.org/10.18563/pv.45.2.e2

  Abstract

    Lalieudorhynchus gandi gen. nov. and sp. nov. is a new caseid synapsid from the Permian of the Lodève Basin, Occitanie, France. This new taxon is represented by a partial but well-preserved postcranial skeleton, and is characterized by the following apomorphies: a transverse section of the sacral and anterior caudal neural spines with a very thin keel-like process anteriorly, a slender dorsal tip of the dorsal and caudal spines, a narrow distal end of the first sacral rib, a fossa on triceps process of metacoracoid, and a very large distal tarsal 1 of same width than the astragalus, with nearly all sides being shallowly concave.
    The skeleton corresponds to a sub-adult individual that was excavated from the La Lieude Formation dated as Roadian-Capitanian (Guadalupian). A sedimentological and taphonomical analysis of the type locality, together with preliminary osteohistological observations, suggest that this new French caseid was rather aquatic, as already hypothesised for other large forms.
    A phylogenetic analysis of caseids is performed to test the position of this new taxon and to better understand the evolution of the clade: interestingly, Lalieudorhynchus gandi gen. nov. et sp. nov. is closer to the NorthAmerican “Cotylorhynchushancocki than to the other French caseids Ruthenosaurus and Euromycter from the Artinskian of the geographically closer Rodez Basin. These two last caseids document the Artinskian radiation of the clade, which remained diverse until Olson’s extinction. Caseids survived, as Lalieudorhynchus is one of the youngest representatives of the clade, and may have used novel ecological strategies to access their vegetarian food sources.

      


  PV article infos

Published in 45-2 (2022)

PDF
Enigmatic rodents from Lavergne, a late middle Eocene (MP 16) fissure-filling of the Quercy Phosphorites (Southwest France)
 
Monique Vianey-Liaud Logo, Romain Weppe Logo and Laurent Marivaux Logo
Published online: 08/04/2024

Keywords: diversity; late Bartonian; Rodentia; taxonomy; Theridomyidae

https://doi.org/10.18563/pv.47.2.e1

  Abstract

    Two somewhat “odd” taxa of theridomyid rodents, one formerly known (Bernardia marandati Vianey-Liaud, 1991) and the other new (Idicia vidalenci gen. et sp. nov.) are discussed from a taxonomical and taphonomical perspectives. These two rodents were found at Lavergne, a late middle Eocene (MP16) “phosphatière” from the Quercy (Southwest France). The genus Bernardia, being preoccupied by a scale insect (Bernardia Ashmead, 1881), is here renamed Burgia. We benefit from this nomenclatural change to describe additional new dental specimens of this patriotheridomyine species, including a previously undescribed locus (P4). The other theridomyid from Lavergne, Idicia vidalenci gen. et sp. nov., so far documented by a mandible preserving two teeth (m2-m3) is a new taxon of peculiar occlusal morphology, and whose subfamilial affinities remain unknown. These two peculiar theridomyids recorded at Lavergne are found nowhere else, whether in coeval localities in Quercy or elsewhere in Western Europe. We discuss the possible causes of their unique presence at Lavergne.
      


  PV article infos

Published in 47-2 (2024)

PDF
Lissamphibians from Dams (Quercy, SW France): Taxonomic identification and evolution across the Eocene-Oligocene transition
Alfred Lemierre Logo and Maeva J. Orliac Logo
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)

PDF
Fossil snakes from the Palaeocene of São José de Itaboraí, Brazil Part III. Ungaliophiinae, Booids incertae sedis, and Caenophidia. Summary, update and discussion of the snake fauna from the locality
Jean-Claude Rage Logo
Published online: 16/12/2008

Keywords: booid-grade incertae sedis; Brazil; Caenophidia; New taxa; Palaeocene; Russellophiidae; Snakes; tropidophiids; Ungaliophiinae

https://doi.org/10.18563/pv.36.1-4.37-73

  Abstract

    Aside from Madtsoiidae, anilioids, and Boidae that were studied previously, the middle Palaeocene of ltaborai (BraziI) has produced Ungaliophiinae ("tropidophiids"), booid-grade snakes incertae sedis, and a possible Russellophiidae (Caenophidia) that are described in the present article. This article is the third and final report on the snakes from the locality. The Ungaliophiinae (Paraungaliophis pricei gen. et sp. nov.) are rare whereas the booid-grade snakes incertae sedis (ltaboraiophis depressus gen. et sp. nov., Paulacoutophis perplexus gen. et sp. nov.) are more frequent. A single vertebra is referred to the Russellophiidae (Caenophidia) with reservation. An update of the whole fauna of snakes from ltaborai is provided. Hechtophis austrinus that was tentatively referred to the erycine Boidae is now regarded as a Boidae incertae sedis. Most snakes from Itaborai are known only from the locality. Astonishingly, only the ailioids Coniophis cf. C. precedens gives possible evidence of interchanges between South and North America. The fauna of snakes from Itaborai, as well as the other Palaeocene faunas of snakes from South America are distinct from those of the Cretaceous and the Eocene of South America; they appear to be more different from the Cretaceous faunas than from those of the Eocene. The fauna from Itaborai is the richest and most diverse assemblage of snakes from the Palaeocene worldwide; it shares only a few taxa with other Palaeocene localities. 


  PV article infos

Published in Vol. 36, Fasc. 1-4 (2008)

PDF
Eggshell microstructure and porosity of the Nicobar scrubfowl (Megapodius Nicobariensis, great Nicobar island, India)
Géraldine Garcia Logo, Ashu Khosla Logo, Ashok Sahni Logo and Monique Vianey-Liaud Logo
Published online: 16/12/2008

Keywords: conductance porosity; eggshell microstructure; incubation conditions; Megapodes

https://doi.org/10.18563/pv.36.1-4.75-88

  Abstract

    The eggshell of Nicobar scrubfowl (Megapodius nicobariensis) is described for the first time. Its egg porosity is calculated and discussed with data from several taxa (another megapode, some extant and fossil reptiles including a titanosaur group) in order to compare incubation types with eggshell structure. Eggshell microstructure reflects first phylogenetic traits and does not seem to have developed major adaptative features due to the incubation conditions, except for the pore canals. 


  PV article infos

Published in Vol. 36, Fasc. 1-4 (2008)

PDF
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
Published online: 30/04/2014

Keywords: Chattian; Elasmobranchii; North Sea Basin; Scyliorhinidae; Scyliorhinus

https://doi.org/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. 


  PV article infos

Published in Vol.38-1 (2014)

PDF
New Squalicorax species (Neoselachii: Lamniformes) from the Lower Maastrichtian of Ganntour phosphate deposit, Morocco
Henri Cappetta Logo, Sylvain Adnet Logo, Driss Akkrim and Mohammed Amalik
Published online: 05/12/2014

Keywords: Anacoracidae; Chondrichthyes; Maastrichtian; Morocco; New taxa

https://doi.org/10.18563/pv.38.2.e3

  Abstract

    Two new Squalicorax species, S. benguerirensis nov. sp. and S. microserratus nov. sp. are described from the Lower Maastrichtian of the Benguérir phosphate open mine, Ganntour deposit, Morocco. The species S. benguerirensis nov. sp. was classically assigned to S. yangaensis since Arambourg (1952) and has been also recognized in coeval deposits from eastern USA to Mid-East. The species S. microserratus nov. sp. correspond to the lateral teeth of S. kaupi as reported by Arambourg (1952) and which is now referred in fact to S. bassanii. The comparison of these two new species with other Anacoracids, known in Moroccan or elsewhere, allows highlighting the great taxonomic and ecological diversities of this family during the Cretaceous.
      


  PV article infos

Published in Vol.38-2 (2014)

PDF
Les Pseudosciuridae (Mammalia, Rodentia) de l'Eocène moyen de Bouxwiller, Egerkingen et Lissieu.
Jean-Louis Hartenberger
Published online: 30/10/1969

Keywords: Bouxwiller; cranium; Egerkingen; Middle Eocene; Rodents

https://doi.org/10.18563/pv.3.2.27-64

  Abstract

    The description of new material from three classic middle Eocene localities of western Europe permits the addition of details to the systematics of primitive Pseudosciurids. The cranial anatomy of Protadelomys cartieri (STEHLIN and SCHAUB) from Egerkingen is described here and compared to that of the Adelomyines from the late Eocene, until now the only ones known. The morphologic and biometric study of the dentition of P. cartieri compared to that of P. alsaticus n. sp. from Bouxwiller and P. Iugdunensis n. sp. from Lissieu, forms respectively older and younger than P. cartieri, permits the evolutionary tendencies of the group to be demonstrated and shows that notable differences in age exist between these localities. This ensemble of forms can constitute a valuable guide lineage in the establishment of a fine stratigraphy of the period. Other less well known lineages are present at Egerkingen along with P. cartieri. They can be related to genera that have been noted int he late Eocene. In conclusion, a criticism of recent zonation proposals, made by divers authors, completes this article. 


  PV article infos

Published in Vol. 03, Fasc. 2 (1969)

PDF
Avant-propos
Marc Godinot Logo and Phillip D. Gingerich Logo
Published online: 16/12/1996

Keywords: D.E.Russell

  Abstract

    Le présent volume est l'aboutissement d'un projet né il y a presque cinq ans. En décembre 1991, l'un d'entre nous (MG) prenait des contacts en vue de proposer un symposium sur les mammifères fossiles, dédié à D.E. Russell, dans le programme du 4e Congrès de la European Society for Evolutionary Biology. Ce congrès, baptisé "Evolution 93", devait se tenir à Montpellier en août 1993. Son Comité d'Organisation, animé par F. Catzeflis, recherchait des organisateurs de symposiums. L'idée fut acceptée avec enthousiasme par le second d'entre nous (PDG), et le titre de notre Symposium fut précisé: " Palaeobiology and Evolution of Early Cenozoic Mammals - A Symposium in Honor of D.E. Russell". Le projet fut formellement accepté par le Comité d'Organisation en avril 1992. 


  PV article infos

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

PDF
A new vertebrate locality in the eifelian of the khush-yeilagh formation, Eastern Alborz, Iran
Alain Blieck, Farrokh Golshani, Daniel Goujet, Amir Hamdi, Philippe Janvier Logo, Elga Mark-Kurik and Michel Martin
Published online: 01/02/1980

Keywords: Devonian; Iran; khush-yeilagh formation; Vertebrate

https://doi.org/10.18563/pv.9.5.133-154

  Abstract

    A new Devonian vertebrste locality has been discovered in 1976 in the basal part of the Khush-Yeilagh Formation in the eastern Alborz Mountains of Iran. The fossils occur in a band one centimeter thick which is identifiable at other outcrops in the area. A preliminary study of the remains has yielded the following faunal list : Placodermata (Phlyctaeniida indet.. Groenlandaspididae indet.. Coccosteidae indet., Holonema sp., Ptyctodontida indet., Antiarcha indet., Bothriolepis cf. kwangtungensis), Elasmobranchii (Ctenacanthidae indet.), Acanthodii (Gyracanthus sp., « Onchus » overathensis, Ischnacanthiforme indet.), Dipnoi (? Dipteridae indet.), « Crossopterygii ›› (Onychodus cf. sigmoides, Holoptychiidae indet., Osteolepididae indet.). This fauna is older than the Middle Givetian and probably of Middle or Lower Eifelian age. Owing to its diversity, it may prove possible to use it in the future as a reference fauna for the study of the Devonian vertebrates in Central Asia and the Middle East. 


  PV article infos

Published in Vol. 09, Fasc. 5 (1980)

PDF
L'anatomie de Lyrocephaliscus euri (wiman), Trématosaure du Trias inférieur du Spitsberg : arrière-crâne, squelette axial et ceinture scapulaire.
Jean-Michel Mazin Logo and Philippe Janvier Logo
Published online: 30/06/1983

Keywords: skull anatomy; Spitsbergen; Trematosaurs; Trias

https://doi.org/10.18563/pv.13.1-2.13-31

  Abstract

    The formic acid preparation of a nodule collected from the Lower Triassic of Spitsbergen, and containing a skull with some associated postcranial elements of Lyrocephaliscus euri (WIMAN), precises and enriches previous descriptions of the reputedly well-known trematosaur. lt permits more detailed descriptions of the occipital region, of the course of the carotid arteries and collateral vessels, and refutes the previous description of a stapedial foramen in trematosaurs. The discovery of pleurocentres associated with the other vertebral components confirms the primitive rhachitomy of trematosaurs. 


  PV article infos

Published in Vol. 13, Fasc. 1-2 (1983)

PDF
Les Gruiformes (Aves) des phosphorites du Quercy (France). 1. sous-ordre cariamae (Cariamidae et Phorusrhacidae), systématique et biostratigraphie.
Cécile Mourer-Chauviré Logo
Published online: 30/11/1983

Keywords: Aves; Biostratigraphy; Birds; Cariamae; gruiformes; Quercy Phosphorites; Systematics

https://doi.org/10.18563/pv.13.4.83-143

  Abstract

    The revision of the old collections of fossil birds from the “Phosphorites du Quercy” and the study of new material give the following results (Gruiformes, Cariamae) :  The humeri and most of the carpometacarpi described under the name Filholornis belong in Elaphrocnemus. The ulnae ascribed to Fïlholornis belong in Idiornis. Most of the post-cranial elements of the genera Elaphrocnemus and Idiornis are described and show great similarities with recent Cariamidae and Opisthocomidae, and fossil Bathornithinae.  A new genus and a new species, Oblitavis insolitus, are created in the sub-family Idiornithinae; two new species are described in the genera Elaphrocnemus (E. brodkorbz) and Idiornis (I. itardiensis), and the species Elaphrocnemus gracilis is transferred to the genus Idiornis.  The genus Propelargus Lydekker is transferred from the family Ciconiidae to Cariamidae.  A new generic name, Occitaniavis, is created for the species Geranopsis elatus, which belong in Cariamidae, while the type-species of the genus, Geranopsis hastingsiae, is a member of the Gruidae.  The affinities between the Quercy avifauna and the Neotropical one is emphasized by the occurrence of Phorusrhacidae, previously known only from the Cenozoic of South America and the Late Pliocene or Early Pleistocene of North America. Thanks to the material collected during the new excavations, the stratigraphical position of most of the species is stated precisely, and evolutionary lineages are outlined. This study shows that the suborder Cariamae, presently restricted to two South American genera, was already extremely diversified during the Eocene, and widespread in Europe and North America. 


  PV article infos

Published in Vol. 13, Fasc. 4 (1983)

PDF
Fossil mammals and the age of the changxindian formation, Northeastern China
Spencer G. Lucas
Published online: 16/12/1996

Keywords: Changxindian Formation; China; Eocene; Fossil mammals

  Abstract

    Re-evaluation of the small collection of mammal fossils from the Changxindian Formation near Beijing, China indicates the following taxa are present: Eutheria, Hypsimilus beifingensis, cf. Miacis sp., Anthracotheriidae and Forstercooperia grandis. The presence of Forstercooperia grandis indicates an Irdinmanhan age and does not support previous assignment of a Sharamurunian age to the Changxindian Formation. 


  PV article infos

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

PDF
Crivadiatherium iliescui n. sp., nouvel Embrithopode (Mammalia) dans le Paléogène ancien de la dépression de Hateg (Roumanie).
Constin Radulesco and Jean Sudre
Published online: 30/12/1985

Keywords: Embrithopods; Late Eocene; Paleobiogeography; Romania

https://doi.org/10.18563/pv.15.3.139-157

  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. 


  PV article infos

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

PDF
The endocranial cast and encephalization quotient of Ptilodus (Multituberculata, Mammalia)
David W. Krause Logo and Zofia Kielan-Jaworowska Logo
Published online: 11/02/1993

Keywords: encephaIization quotient; endocranial cast; Montana; Multituberculata; olfactory bulbs; Paleocene; Ptilodus

https://doi.org/10.18563/pv.22.2-3.99-112

  Abstract

    Simpson (1937a) reconstructed the brain of the Paleocene multituberculate Ptilodus as having the olfactory bulbs widest anteriorly, an unusual condition among mammals. Slight preparation and reexamination of the endocast specimens of Ptilodus reveals that the olfactory bulbs in fact taper anteriorly, as in the recently-described endocranial casts of three multituberculate species from the Late Cretaceous of Asia, and as in those of other mammals. The brain of Ptilodus was therefore essentially of the same general pattem as in other multituberculates. Ptilodus differs, however, in having the vermis more deeply inserted between the cerebral hemispheres. Other details concerning the endocast morphology of Ptilodus are clarified.

    The encephalization quotient (EQ) of Ptilodus is recalculated from revised estimates of both endocranial volume and body mass to fall somewhere within a broad range of values; from 0.41 to 0.62 if the olfactory bulbs are included and from 0.37 to 0.55 if they are not. In any case, the relative brain size of Ptilodus is roughly equivalent to that of Chulsanbaatar, the only other multituberculate for which EQ has been calculated, but considerably smaller than that of an average extant mammnal. 


  PV article infos

Published in Vol. 22, Fasc. 2-3 (1993)

PDF
Dilambodont Molars :a functional interpretation of their evolution
Percy M. Butler
Published online: 16/12/1996

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. 


  PV article infos

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

PDF
Un Haplobunodontidae nouveau Hallebune krumbegeli nov.gen. nov.sp. (Artiodactyla, Mammalia) dans l'Eocène moyen du Geiseltal près Halle (Sachsen-Anhalt, Allemagne)
Jorg Erfurt and Jean Sudre
Published online: 14/06/1995

Keywords: Artiodactyla; Geiseltal; Germany; Mammal; Middle Eocene; new gen.; new sp.

  Abstract

    A new genus and species of haplobunodontid artiodactyl, Hallebune krumbiegeli nov. gen. nov. sp., is described from the middle Eocene Geiseltal Fauna (Saxon-Anhalt, Germany). Its stratigraphic range is restricted to the MP 13 ("obere Mittelkohle") of the Geiseltalian. The material consists of seven fragments, representing both upper and lower jaws. It is indicated, that H. krumbiegeli was a small bunodont herbivore. The size and primitive character of the teeth suggest that the genus possibly is directly derived from Diacodexeidae.The new material forms the basis for reinterpreting the haplobunodontid phylogeny. 


  PV article infos

Published in Vol. 24, Fasc. 1-2 (1995)

PDF
A primitive Emballonurid bat (Chiroptera, Mammalia) from the Earliest Eocene of England
Jerry J. Hooker
Published online: 16/12/1996

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. 


  PV article infos

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

PDF
Artiodactyla from the early Eocene of Kyrgyzstan
Alexander Averianov Logo
Published online: 16/12/1996

Keywords: Artiodactyla; Asia; Diacodexeidae; Eocene; Kyrgyzstan

  Abstract

    Isolated upper cheek teeth of the primitive artiodactyl Diacodexis sp., upper molars of Eolantianius russelli gen. et sp. nov. (Diacodexeidae), two lower molars tentatively referred to Eolantianius russelli gen. et sp. nov., and astragali of Diacodexeidae indet. are described from the early Eocene (late Ypresian) of locality Andarak 2 in Kyrgyzstan. 


  PV article infos

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

PDF
Une nouvelle espèce de Steneosaurus (Thalattosuchia, Teleosauridae) dans le Callovien du Poitou (France) et la systématique des Steneosaurus longirostres du Jurassique moyen d'Europe Occidentale.
Patrick Vignaud Logo
Published online: 15/09/1998

Keywords: middle Jurassic; nov. sp.; phylogenetic relationships; skulls; Steneosaurus pictaviensis; Systematics; thalattosuchian crocodile

  Abstract

    The study of all the available skulls allows us to review the systematic relationships of the longirostrine Steneosaurus from the Middle Jurassic of western Europe. Up to now, Aalenian and Bajocian deposits have not yielded any significant Steneosaurus remain. In the Bathonian, the only valid longirostrine species, S. megistorhynchus, is known in the Britain-Normandy Basin, the Poitou and the Lorraine. In the Callovian, most of the longirostrine Steneosaurus remains can be attributed to the species S. leedsi. Nevertheless, some remains from the Middle Callovian of Poitou (France) show important differences with S. leedsi. A new Steneosaurus species, only known in Poitou, is created and named S. pictaviensis. The specific characters are carried by the skull (preorbital pit well marked, orbit and ptetygoid fossae shapes), by the mandible (symphysis shape) and by the teeth (ornamentation). S. megistorhynchus is probably situated near the stem of the Callovian species but remains from the Bathonian and Lower Callovian are very scarce and it is very difficult to precise the phylogenetic relationships between the longirostrine species of the Middle Jurassic.
      


  PV article infos

Published in Vol. 27, Fasc. 1-2 (1998)

PDF

Page 13 of 19, showing 20 record(s) out of 365 total