The systematic position of the Triassic ornithischian dinosaur Lycorhinus angustidens

A topotype of the poorly known reptile Lycorhinus angustidens Haughton (1924) is described. This specimen demonstrates that Lycorhinus is a genuine ornithischian dinosaur of late Triassic age and not, as previously supposed, a therapsid. The generic term 'Heterodonto-saurus' Crompton & Charig (1962) is regarded as an invalid junior synonym for Lycorhinus and is discarded–though the species tucki (now referred to Lycorhinus) is retained as distinct from angustidens on the basis of slight differences in tooth structure. Lycorhinus is included within the family Hypsilophodontidae of the suborder Ornithopoda.     

A primitive ornithischian dinosaur from the Late Triassic of South Africa, and the early evolution and diversification of Ornithischia

Although the group played an important role in the evolution of Late Mesozoic terrestrial ecosystems, the early evolutionary history of the ornithischian dinosaurs remains poorly understood. Here, we report on a new primitive ornithischian, Eocursor parvus gen. et sp. nov., from the Late Triassic (?Norian) Lower Elliot Formation of South Africa. Eocursor is known from a single specimen comprising substantial cranial and postcranial material and represents the most complete Triassic member of Ornithischia, providing the earliest evidence for the acquisition of many key ornithischian postcranial characters, including an opisthopubic pelvis. A new phylogenetic analysis positions this taxon near the base of Ornithischia, as the sister taxon to the important and diverse clade Genasauria. The problematic clade Heterodontosauridae is also positioned basal to Genasauria, suggesting that an enlarged grasping manus may represent a plesiomorphic ornithischian condition. This analysis provides additional phylogenetic support for limited ornithischian diversity during the Late Triassic, and suggests that several major ornithischian clades may have originated later than generally believed. There are few morphological differences between Late Triassic and Early Jurassic ornithischians, supporting previous suggestions that the Early Jurassic ornithischian radiation may simply represent the filling of vacant ecological space following Late Triassic terrestrial extinctions.     

Biometric and morphometric approaches on Lower Hettangian dinosaur footprints from the Rodez Strait (Aveyron,France)

Along the southern crystalline border of the Rouergue, the detrital Sandstones-variegated Mudstones Formation and the Dolomitic Formation yields numerous dinosaur footprints from the Earliest Hettangian. Among the 25 sites distributed along the 40 km-long transect between Marcillac-Vallon and Saint-Geniez-d’Olt, two of them, Puech de Castres and Le Bouyssou, have yielded abundant ichnites in various well-defined stratigraphic units. The combined analysis of these footprints with biometric and morphometric methods (Fourier analysis) warrants their identification to Grallator, Eubrontes and Dilophosauripus. The dual methodological approach also reveals two new morphotypes previously unknown in the Causses Basin. Moreover, the footprints assigned to Grallator and Eubrontes tend to be morphologically similar, suggesting that they might correspond to a same taxon of Coelophysoidea theropod at different growth stages. This dinosaur fauna was living in a vast floodplain, in which fluvial channels carried southward the detrital material coming from the Rouergue substratum. The Dolomitic Formation was deposited in the context of a northward marine transgression during which shallow and aerial environments prevailed in the area.     

OnStaurikosaums pricei,an early saurischian dinosaur from the Triassic of Brazil,with notes on the Herrerasauridae and Poposauridae

The anatomy of the saurischian dinosaurStaurikosaums pricei Colbert from the Santa Maria Formation (Middle or Upper Triassic) of Rio do Sul, Brazil is redescribed.Staurikosaurus has 9 (or possibly 10) short cervicals, 15 dorsals and 2 sacral vertebrae, a modified brachyiliac pelvic girdle and an elongate hindlimb with the tibia longer than the femur. The new family Staurikosauridae is erected, the Herrerasauridae is redefined, and both families are considered to be Saurischia incertae sedis. The distal part of the “femur” ofPoposaurus gracilis Mehl (Upper Triassic, North America) is the ventral part of the pubes with a footed distal end but, because some members of the Poposauridae have an imperforate acetabulum, this family is transferred from the Saurischia (Theropoda, Carnosauria) to the Thecodontia (Pseudosuchia).     

Structure of fossil dinosaur eggshell from the Aix Basin,France

At least four types of dinosaur eggshell are distinguished among samples of fossil eggshell from Late Cretaceous deposits of southern France. Recognition is based on shell microstructure, porosity, and shell thickness. Estimated values of water vapour conductance for these dinosaur eggshells are much greather than predicted for avian eggs, suggesting that the eggs were incubated under conditions of high humidity, such as would occur underground.     

A new heterodontosaurid dinosaur (Reptilia: Ornithischia) from the Upper Triassic Red Beds of Lesotho

A new species of ornithischian dinosaur ( Lycorhinus consors sp. nov.) is established on a skull from the Upper Triassic Red Beds of Lesotho. This ornithischian is assigned to the family Heterodontosauridae of the suborder Ornithopoda. The dinosaurs of the family Heterodonto-sauridae are reviewed: Geranosaurus atavus Broom (1911) is considered a nomendubium and the genus name Heterodontosaurus Crompton & Charig (1962) is held to be a junior synonym for Lycorhinus Haughton (1924).
Functional and palaeoecological implications of the heterodontosaurid dentition are discussed. The pattern of tooth wear may reflect a highly specialized jaw action which involved protraction and retraction of the mandible to produce a grinding effect between upper and lower cheek teeth. Lycorhinus consors is presumed to be a female heterodontosaurid because it differs from all other heterodontosaurids in lacking caniniform tusks. It is suggested that the tusks of heterodontosaurids were functionally analogous to those of tayassuids and tragulids and that they were employed as weapons for intra-specific combat and defence. Dental peculiarities indicate that tooth replacement processes were suppressed in heterodontosaurids; replacement of the teeth seems to have been restricted to a brief period each year (presumably when heterodontosaurids underwent aestivation or hibernation).
A new diagnosis is formulated for the family Heterodontosauridae. The relationships of early ornithopod dinosaurs are briefly reviewed and a new classification is proposed. Ten families of ornithopod dinosaurs are recognized; these are ranked in two grades-one (named Dolichopoda) representing the conservative main stem of the ornithischian phylogenetic tree and the other (named Brachypoda) comprising the several more advanced lines of ornithopod evolution.     

The Kuehneotheriidae (Mammaliaformes) from Saint-Nicolas-de-Port (Upper Triassic,France): a Systematic Review

The origin and first diversification of mammals in the Upper Triassic remain poorly understood, in part because many fossil discoveries are not fully studied, and in part because the material remains poor. The Saint-Nicolas-de-Port quarry (Rhaetian, France) is the second most important locality that yielded remains of Kuehneotherium, after the fissure-fillings of the Glamorganshire (Lower Jurassic, Wales). This study identifies one new species of Kuehneotherium, K. stanislavi, sp. nov., and a new genus of Kuehneotheriidae, Fluctuodon necmergor, gen. et sp. nov. For these two new species, lower and upper molars are described and the first reconstructions of the postcanine row are proposed. Comparisons with material of Kuehneotherium from other Upper Triassic sites (Syren in Luxembourg, Emborough in England, and Jameson Land in Greenland) suggest two distinct Upper Triassic specific kuehneotheriid assemblages, respectively, west and east of the London Brabant Massif. They also suggest that the extinction event during the Triassic/Jurassic transition did not have a great impact on Kuehneotherium.     

On an Ornithomimid dinosaur (Saurischia, Ornithomimosauria) from the Cenomanian of Fergana

A fragmentary coracoid of Ornithomimidae indet. from the Lower Cenomanian of the Abshir River (Kyrgyzstan) is described. This is the first record of this group in a Cenomanian locality of Fergana. The coracoid from the Abshir locality is similar in the lateral deflection of the glenoid to an endemic group of Asiatic Ornithomimidae that includes Anserimimus, Gallimimus, and taxa from the Cenomanian and Turonian of western Uzbekistan. It is most similar to the unnamed ornithomimid from the Cenomanian of Karakalpakia in having a distinct vertical crest that borders anteriorly a depression for the coracobrachialis brevis muscle. Dinosaurs recorded in the Cenomanian of Fergana are reviewed.     

Firewood management and woodland exploitation during the late Neolithic at Lac de Chalain (Jura,France)

The paper presents results of the charcoal analysis from the lakeshore settlement of Chalain 4 in the French Jura (Dép. Franche-Comté), dated by dendrochronology from 3040 to 3000 bc. The investigated material comes from waterlogged organic layers (excluding fire events) where charcoals are assumed to be the residues of domestic fires only. The anthracological (charcoal) analysis reveals a complex domestic firewood management in balance with the social organisation and the technical and economic systems of the settlement. This firewood economy is characterised by the avoidance of wood species intended for other activities, such as building or foddering, and by the preferential use of wood less than 10 cm in diameter. The areas from which firewood was obtained are also connected to woodland clearance for cultivated land, which suggests that firewood was gathered along the paths, which were travelled daily.     

Two new ornithischian dinosaurs (Hypsilophodontia,Ornithopoda) from the Late Jurassic of Russia

Two new dinosaurs, Kulindapteryx ukureica gen. et sp. nov. (Jeholosauridae) and Daurosaurus olovus gen. et sp. nov. (Hypsilophodontidae) from the Ukureisk Formation (?Tithonian, Upper Jurassic) of the Kulinda locality in Transbaikalia (Russia) are described and assigned to Ornithopoda (Ornithischia). The origin and homology of the so-called obturator process of the ischium of Ornithopoda and Theropoda are discussed. The families Jeholosauridae and Hypsilophodontidae as well as Lesothosauridae are considered to belong to the infraorder Hypsilophodontia (Ornithopoda, Ornithischia). It is shown that hypsilophodontians had skin scales divided into bristles.     

Triassic magnetic overprints related to albitization in granites from the Morvan massif (France)

The Morvan massif, located in the northern part of the French Massif Central, shows widespread unusual deep alteration profiles in the Palaeozoic basement rocks (gneisses, granites and rhyolites). They are characterised by overall albitization, chloritisation and haematisation. Albite and chlorite constitute their characteristic mineral paragenesis. Haematite pigmentation comes with this paragenesis and gives an overall pink coloration to the weathered rocks.A paleomagnetic analysis was conducted after detailed petrographical and mineralogical studies of the alteration that lead to the albitized profiles. Special attention was devoted to the occurrence of haematite, the main paleomagnetism carrier, with the though to date this palaeoweathering event. Petrographical checking after heating treatments showed that deshydroxylation of chlorite also led to the formation of secondary haematite. This haematite formed by recrystallization acquired remanence properties and thus superimposed and hided the original magnetic signal. This problem has prevented the extraction of the original magnetic signal especially in the sections made up of rhyolites.Virtual Geomagnetic Poles (VGPs) obtained from the characteristic directions carried by haematite have been compared to the European Apparent Polar Wander Path (APWP). An Early Triassic magnetic overprint has been recorded in the albitized basement rocks of the Morvan massif. The age obtained for this albitization phenomena, strengthens the hypothesis that albitization developed in relation with palaeoweathering processes linked with the Triassic palaeosurface. Therefore, large scale continental weathering could be the main mechanism for Late Permian/Early Triassic remagnetizations which are widespread throughout the Palaeozoic formations of western Europe.As far as we know, this is the first time that deep palaeoweathering phenomena affecting hard and non-disaggregated weathered rocks of the basement have been directly dated. Palaeomagnetism appears as a precious tool to date alteration events developed in widely and long-lasting emerged areas of the basement.     

Integument structure in ornithischian dinosaurs (Hypsilophodontia,Ornithopoda) from the Late Jurassic of Transbaikalia

Integumentary structures of ornithischain dinosaurs of the taxon Hypsilophodontia (Ornithopoda) from the Ukureiskaya Formation (Upper Jurassic) of the Kulinda locality (Transbaikal Region, Russia) are described in detail. It is shown that members of this group had so-called bristle scales, integumentary appendages previously unknown in ornithischian dinosaurs. These are relatively small horn plates embedded in the skin, the distal margin of which has several long, flat, and probably constantly growing bristles. The monobristle variant of bristle scale is probably homologous to the protofeather of theropods; if this is the case, it is possible to reconstruct the protofeather as an elongated and constantly growing scale.     

Paleosols,trace fossils,and precipitation estimates of the uppermost Triassic strata in northern New Mexico

This study provides a detailed pedogenic evaluation of two Upper Triassic (Late Norian through Rhaetian) stratigraphic intervals in New Mexico in order to assess the climate and ecology of the Latest Triassic, which ended in a mass extinction. The two study areas are located in north–central and east-central New Mexico and are separated by 200 km. Each section contains abundant paleosols of varying maturity with features that reflect an arid to semiarid climate. There is little pedogenic variation throughout the strata at each location, and a typical paleosol profile is about 1 m thick and has an AB–Bw–Bk–BC horizon succession. Bkm, Bss, Bssk, or Bssg horizons are present in some paleosols. Micromorphological features suggest dominantly well-drained sola (e.g., abundant carbonate nodules, illuviated clay) with minor periods of moist or saturated conditions (e.g., FeMn concretions, FeMn coatings and hypocoatings, sepic-plasmic fabrics). Trace fossils are abundant in these strata and are dominated by Taenidium serpentinum and root traces. Depth-to-carbonate functions estimate that mean annual precipitation was between 200 and 450 +/? 95 mm. Relative to location 1 (eastern New Mexico), location 2 (north–central New Mexico) produced higher paleo-precipitation estimates and has stronger and more abundant sepic-plasmic fabrics in thin sections. The presence of a gleyed paleosol, Camborygma eumnkenomos, and slickensides at location 2 also suggests conditions wetter than at location 1. Taxonomically, all of the paleosols in this study appear to be Entisols or Aridisols and can be grouped into seven representative pedotypes of varying maturity. By comparing these paleosols to modern soils, this study demonstrates that the Late Triassic Western Interior during the Late Norian to Rhaetian was arid to semiarid and supported a desert shrub environment that had localized and periodic moist or saturated soil conditions.     

Thyreophoran vertebrae from the Callovian (Middle Jurassic) of the Vaches Noires cliffs (Normandy,France), with remarks on the dinosaur assemblage from the Vaches Noires

Two associated incomplete thyreophoran dorsal vertebrae from the Callovian Marnes de Dives Formation of the Vaches Noires cliffs, on the Normandy coast, are referred to an indeterminate stegosaur that appears to be different from Lexovisaurus, previously reported from the Callovian of western France. These vertebrae are the first evidence of thyreophorans from the Vaches Noires and complement the dinosaur assemblage from this locality, which hitherto consisted of several theropod taxa and an indeterminate sauropod. The dinosaur record from the Vaches Noires is heavily dominated by theropods and this imbalance is difficult to explain. A possible explanation may be that the dinosaur sample from the Vaches Noires is too small to be statistically significant and representative of the original faunal assemblage from which it is derived.     

Epidemiology of canine babesiosis in relation to the activity ofDermacentor reticulatus in southern Jura (France)

Dates of onset of canine babesiosis within a hyperendemic focus in France (Rhone Valley, south of Jura and north of the Alps) were compared to the seasonal population level of the adult stage ofDermacentor reticulatus over a 12-month period (December 1982–November 1983). Cases of babesiosis occurred in spring and fall when adultD. reticulatus were active. The fluctuations of the vector tick population and the onsets of canine babesiosis were also correlated with climatic changes: no tick activity or clinical cases of disease were detected in winter (low temperature) or in summer. The slight disparities observed between both distributions might be explained by various factors such as the development of immunity against the parasites, the intervals between tick bites and appearance of symptoms of the disease, or the asynchrony between different biotopes.     

On the anatomy and relationships ofEfraasia diagnostica (Huene) n. gen., a prosauropod dinosaur (Reptilia: Saurischia) from the Upper Triassic of Germany

Palaeosaurus (?) diagnosticus Huene from the Stubensandstone (Upper Triassic, Norian) of Nordwürttemberg, Germany is made the type species of a new genus of prosauropod dinosaurEfraasia, which is referred to the family Anchisauridae. The anatomy ofEfraasia diagnostica is conservative and it was an ideal ancestor for the later and more specializedAnchisaurus polyzelus of North America. The slenderness of the manus and pes ofEfraasia andAnchisaurus is matched amongst prosauropods only by the feet ofGyposaurus capensis andThecodontosaurus antiquus. Staurikosaurus pricei Colbert from the Upper Triassic of Brazil is probably a very primitive theropod dinosaur.     

Anachronistic and unusual carbonate facies in uppermost Lower Triassic rocks of the western Balkanides,Bulgaria

Anachronistic and unusual carbonate facies (AUCFs) are identified in four localities with exposed Spathian strata in the western Balkanides. These include thin-bedded micritic limestone, flat-pebble breccia/conglomerate, mud-chip conglomerate, limestone-marl ribbon rock, vermicular limestone, and microbial oolite. Their depositional and/or early diagenetic origin is interpreted on the basis of petrographic characteristics, results from previous studies, and comparison with analogues from the geological record. Various controlling factors are distinguished in the context of their relative influence on global, regional, or local scale, i.e., environmental conditions (high degree of CaCO₃ supersaturation, fluctuations in oxygen levels and salinity), biological controls (bioturbation, microbial blooms, scarcity or abundance of metazoans), and uniformitarian sedimentary processes (wave agitation, storm action, terrigenous input, seismic shocks). Most of the AUCFs are assigned to features associated with enhanced CaCO₃ precipitation, while the vermicular limestones belong to fabrics that formed due to limited biologic activity. The thin-bedded micritic limestones, flat-pebble breccias/conglomerates, and limestone-marl ribbon rocks represent anachronistic facies, while the remaining AUCFs are regarded as unusual sedimentary features and fabrics. This study reports a new occurrence of diverse Spathian AUCFs formed in subtidal settings besides those described from the southwestern USA and south China. The results show that anomalous paleoceanographic conditions for carbonate sedimentation persisted locally in the shallow Western Tethys until late Early Triassic time.     

Fabrosauridae,the basal family of ornithischian dinosaurs (Reptilia: Ornithopoda)

In fabrosaurids the upper jaw is flat and the lower jaw is slender so the ’cheek’ teeth are marginal and not inset as is the case in all other ornithischian dinosaurs. The ’cheek’ teeth of fabrosaurids have anteroposteriorly expanded crowns but lack wear surfaces formed by tooth to tooth contact. Two genera are recognized from the Triassic-Jurassic boundary of Lesotho with good material previously referred toFabrosaurus as a new genus that represents the most conservative ornithopod described to date. The anatomy ofNanosaurus (Upper Jurassic, U.S.A.) andEchinodon (Jurassic-Cretaceous boundary, England) is redescribed; in both genera the tooth bearing bone of the lower jaw is deepened posteriorly and inEchinodon there is a true canine tooth in the upper jaw.