A new Semionotid (Actinopterygii,Neopterygii) from the Late Jurassic–Early Cretaceous of Thailand

A new semionotid fish, Lepidotes buddhabutrensis n. sp., is described from the continental Late Jurassic–Early Cretaceous Phu Kradung Formation, Phu Nam Jun, Kalasin Province. L. buddhabutrensis is characterized notably by the pattern of its cheek bones, by its short preorbital region, and by its numerous and well-developed premaxillary teeth. L. buddhabutrensis is provisionally placed in the genus Lepidotes; it shares, however, derived characters with other semionotids, such as Araripelepidotes and Pliodetes. To cite this article: L. Cavin et al., C. R. Palevol 2 (2003).     

Ecology,Systematics and Biogeographical Relationships of Dinosaurs,Including a New Theropod,from the Santana Formation (?Albian,Early Cretaceous) of Brazil

Although rare, dinosaurs are well preserved in calcareous nodules of the Santana Formation (Early Cretaceous, ?Albian) of the Araripe Basin, in northeastern Brazil. So far, including only a spinosauroid and three coelurosaurs, the dinosaur fauna appears depauperate. High theropod diversity in assemblages where other dinosaurs are rare or absent is not unique to the Santana Formation. It is seen also in several other assemblages, including Solnhofen and the Maevarano Formation of Madagascar. We consider several factors, including the occurrence of intraguild predation, the possibility that small theropods could subsist in marginal environments, and reliance on coastal resources, that may have been responsible for this apparent ecological imbalance. A new coelurosaur from the Santana Formation, here formally named Mirischia asymmetrica, is shown to be distinct from Santanaraptor placidus [Kellner, A.W.A. () “Short note on a new dinosaur (Theropoda, Coelurosauria) from the Santana Formation (Romualdo Member, Albian) northeastern Brazil”, Boletim do Museu Nacional, Nova Serie, Rio de Janeiro, Brasil 49, 1–8]. Other theropods from the Santana Formation are briefly reviewed. Mirischia is a compsognathid, more similar to the European Compsognathus than to the Asian Sinosauropteryx.     

Raunsgaardispermum lusitanicum gen. et sp. nov., a new seed with in situ pollen from the Early Cretaceous (probably Berriasian) of Portugal: Further support for the Bennettitales‐Erdtmanithecales‐Gnetales link

Assemblages of Recent and sub-Recent dinoflagellate cysts are described from the southern Beaufort Sea, offshore Mackenzie Delta region, Canadian Arctic, and include the new taxa Spiniferites frigidus Harland &; Reid, Multispinula minuta Harland &; Reid, and Rottnestia amphicavata Dobell &; Norris. These assemblages, which appear to be unique to Arctic waters, are dominated by Operculodinium centrocarpum, and compared to assemblages found in north-temperate seas, also dominated by Operculodinium centrocarpum, are ten times less diverse. The three new species described herein may prove to be indicators of the Arctic environment. Several genera of Recent cysts that were not originally supplied with Latin diagnoses are validated.     

A new peirosaurid (Crocodilyformes) from the Late Cretaceous (Turonian–Coniacian) of Patagonia,Argentina

Peirosauridae is composed of mid- to large-sized terrestrial mesoeucrododylian crocodyliforms distributed throughout Gondwanan landmasses. Here we describe a new peirosaurid that comes from the upper levels of the Portezuelo Formation (Turonian–Coniacian, Upper Cretaceous) from Loma de la Lata, Neuquén Province, Argentina. This specimen consists of some associated bones belonging to a single individual. In order to facilitate comparisons, we recognise two different peirosaurid morphotypes based on skull shape: broad- and narrow-snouted taxa. The new taxon may be related to broad-snouted taxa, especially Gasparinisuchus peirosauroides. The new taxon here reported has strong heterodont dentition when compared with other peirosaurids. As in related forms, the fourth dentary tooth is caniniform, very large, acute and transversely compressed (much more than other peirosaurids), and the anterior dentary teeth have less globular, sharp serrated crowns. Large interalveolar spaces are present between both mandibular and maxillary teeth, a trait only observed on the new taxon. With this addition, we elevate the number of Patagonian peirosaurids to four. Moreover, it represents together with Lomasuchus palpebrosus the second peirosaurid species described for the Portezuelo Formation.     

Draconyx loureiroi,a new camptosauridae (Dinosauria,Ornithopoda) from the Late Jurassic of Lourinhã, Portugal

A new ornithopod dinosaur is described here under the name of Draconyx loureiroi n. gen., n. sp. on teeth, caudal vertebrae, forelimb, hindlimb, and foot material that were found in association in the Late Jurassic-Tithonian of Lourinhã, Portugal. Draconyx is a Camptosauridae related to Camptosaurus.     

Seed Size and Dispersal Systems of Early Cretaceous Angiosperms from Famalicão, Portugal

Seeds and fruits of Early Cretaceous (Barremian-Aptian) angiosperms from the Famalic?o locality in Portugal were analyzed to establish seed and fruit size (volume) distributions and to infer the proportion of animal-dispersed fruits. On the basis of a sample of 106 angiosperm fruit and seed taxa, the average seed size was 0.78 mm3 (range 0.02-6.86 mm3), whereas the average fruit size was 2.06 mm3 (range 0.12-8.34 mm3). Variation in seed size among taxa is smaller than in modern plant communities, but within-taxon variation is similar to that known for extant plants. No significant difference in the size of "fleshy" versus other fruits was observed. The proportion of fleshy fruits was 24.5%. This high figure was surprising and indicates that the significance of animal dispersal during an early stage in angiosperm evolution has been underestimated. We suggest that reptiles and multituberculates, and perhaps other mammals and birds as well, were the likely seed dispersers and that the early angiosperms from Famalic?o probably were herbs or small shrubs that inhabited a semiopen coniferous woodland.     

Planktic foraminifera from the mid-Cretaceous (Barremian–Early Albian) of the North Sea Basin: Palaeoecological and palaeoceanographic implications

A marine Cretaceous succession (Barremian–Albian) of a cored borehole (BGS 81/40), located in the Central North Sea Basin, has been examined with respect to its planktic and benthic foraminiferal content, as well as for calcareous nannofossils. The distribution patterns of foraminifera and calcareous nannofossils allow for a two fold division of the investigated interval. (1) The Barremian–earliest Aptian interval, which reflects a marine, temporary restricted setting. This is indicated by sporadic occurrences of planktic foraminifera with very rare planispiral forms suggesting short-term connections of the Boreal and Tethyan Realms. The benthic foraminiferal assemblages indicate aerobic, sometimes dysaerobic bottom-water conditions. High abundances of nannoconids in the Barremian suggest enhanced stratification and/or warm, oligotrophic surface water. (2) The late Aptian–early Albian interval, which was characterised by an open-oceanic environment with cool and aerobic surface water conditions. Planktic foraminifera are more abundant and diverse than in the lower interval. Trochospiral hedbergellids dominate the foraminiferal assemblages. The episodic occurrences of planispiral, clavate and trochospiral-flattened planktic morphotypes indicate the existence of a seaway between the Boreal and the Tethyan Realms. Aerobic to dysaerobic bottom-water conditions are suggested by the composition of the benthic foraminiferal assemblages. High abundances of cool-water taxa within the calcareous nannofossil assemblages indicate a cooling trend across the latest Aptian and earliest Albian.     

The forgotten remains of a leptocleidid plesiosaur (Sauropterygia: Plesiosauroidea) from the Early Cretaceous of Gronau (Münsterland, Westphalia, Germany)

Gronausaurus wegneri n. gen. n. sp. represents a newly discovered leptocleidid sauropterygian based on one individual from the Early Cretaceous (Berriasian) of Gronau in Westphalia, Germany. The holotype and only known specimen consists of a skeleton, which lacks most of the dermal skull bones, a large number of cervical vertebrae and distal limb elements. Gronausaurus wegneri is unique in having distinct cavities, the subdiapophyseal fossae, below the transverse processes of the pectoral and anterior dorsal vertebrae, that probably stabilised the bones against tensile forces of the rotator and levator muscles in the living animal.     

Cretaceous (Albian to Turonian) radiolarians from chert blocks of the Moni Mélange (Southern Cyprus)

Well-preserved Cretaceous (Albian–Turonian) radiolarians were extracted from radiolarian-bearing chert olistoliths of the Monagroulli Member within the Moni Mélange (Campanian-Maastrichtian, Southern Cyprus). Four assemblages were distinguished: Middle Albian–Lower Cenomanian (Thanarla spoletoensis Zone), Upper Albian–Lower Cenomanian (Thanarla spoletoensis Zone, Dorypyle? anisa Subzone), lowermost Turonian (base of Alievium superbum Zone) and Lower Turonian (Alievium superbum Zone). The radiolarian assemblages are diverse and have taxonomic composition similar to coeval assemblages of Italy and Spain. The sediments of the Monagroulli Member differ from coeval rocks of the Mamonia Complex (western Cyprus) by the more common presence of radiolarian cherts and may have been formed in the distal part of a continental margin with less input of clastic material. A new spicular radiolarian genus Cyprothamnus with 2 new species (C. multifurcatus and C. moniensis) is described from the Lower Turonian strata.     

Plants of Leptostrobus Heer （Czekanowskiales） from the Early Cretaceous and Late Triassic of China, with Discussion of the Genus

Investigation of the Mesozoic seed plant Leptostrobus Heer from the Yangcaogou Formation of the Late Triassic and the Yixian Formation of the Early Cretaceous, Liaoning Province, China, provides new Insight Into Its general morphology and geographical distribution. The materials of L. cancer from the Yixian Formation described herein are later than all the past findings of this species and add to the record of L. cancer during the Early Cretaceous. Based on well-preserved specimens, the specific diagnosis Is slightly emended and the reconstructlon of L. cancer Is perfected. The materials from the Yangcaogou Formation of the Late Triassic are placed in L. spheericus, in addition, we review the history of investigation of the genus Leptostrobus since its establishment in 1876 and discuss the main characteristics of each species.     

An Ornithopod-Dominated Tracksite from the Lower Cretaceous Jiaguan Formation (Barremian–Albian) of Qijiang,South-Central China: New Discoveries,Ichnotaxonomy, Preservation and Palaeoecology

The historically-famous Lotus Fortress site, a deep 1.5–3.0-meter-high, 200-meter-long horizonal notch high up in near-vertical sandstone cliffs comprising the Cretaceous Jiaguan Formation, has been known since the 13th Century as an impregnable defensive position. The site is also extraordinary for having multiple tetrapod track-bearing levels, of which the lower two form the floor of part of the notch, and yield very well preserved asseamblages of ornithopod, bird (avian theropod) and pterosaur tracks. Trackway counts indicate that ornithopods dominate (69%) accounting for at least 165 trackmakers, followed by bird (18%), sauropod (10%), and pterosaur (3%). Previous studies designated Lotus Fortress as the type locality of Caririchnium lotus and Wupus agilis both of which are recognized here as valid ichnotaxa. On the basis of multiple parallel trackways both are interpreted as representing the trackways of gregarious species. C. lotus is redescribed here in detail and interpreted to indicate two age cohorts representing subadults that were sometimes bipedal and larger quadrupedal adults. Two other previously described dinosaurian ichnospecies, are here reinterpreted as underprints and considered nomina dubia. Like a growing number of significant tetrapod tracksites in China the Lotus Fortress site reveals new information about the composition of tetrapod faunas from formations in which the skeletal record is sparse. In particular, the site shows the relatively high abundance of Caririchium in a region where saurischian ichnofaunas are often dominant. It is also the only site known to have yielded Wupus agilis. In combination with information from other tracksites from the Jiaguan formation and other Cretaceous formations in the region, the track record is proving increasingly impotant as a major source of information on the vertebrate faunas of the region. The Lotus Fortress site has been developed as a spectacular, geologically-, paleontologically- and a culturally-significant destination within Qijiang National Geological Park.     

Revision of the lower Aptian (Lower Cretaceous) ammonite species Cheloniceras cornuelianum (d’Orbigny, 1841)

The aim of the present work is to determine the morphological characteristics of the lower Aptian (lower Cretaceous) ammonite species Cheloniceras cornuelianum (d’Orbigny, 1841) (Douvilleiceratinae, Douvilleiceratidae) on the basis of 32 specimens from the Paris Basin (France), including the lectotype of the species and 23 topotype specimens. It is generally admitted that this species occurs in the Deshayesites forbesi-Dufrenoyia furcata zones interval (lower Aptian). Our study has lead to several unexpected results. First, the study sample of C. cornuelianum is very probably younger and has more primitive traits than expected: it is probably dated around the limit between the Deshayesites forbesi and Deshayesites deshayesi zones and is morphologically close to the earlier genus Procheloniceras Spath, 1923. Secondly, the lectotype is an extreme specimen with much derived traits compared to its original population. It constitutes an example of type-specimen not morphologically representative of its original population, responsible of a risk of misinterpretation of the species. Finally, the intraspecific variability and the proportion of asymmetric specimens of the study sample of C. cornuelianum are very important but there is no evidence of sexual dimorphism.     

Evidence of plant–insect interaction in the Early Cretaceous Flora from the Crato Formation,Araripe Basin,Northeast Brazil

The analysis of insect-plant interaction can be provide paleoecological and paleoenvironmental important data for understanding the co-evolution between plants and insects. Since the appearance of the first evidence of leaves damaged by insects, these organisms have evolved together. In the Araripe Basin, the Crato Formation stands out by having abundance and diversity of fossils species of plants and insects. In this work they are documented interaction records in specimens of ferns, gymnosperms and angiosperms, showing a wide variety of types of interactions. Here we analyze 56 fossil specimens from the collections of the Museum of Paleontology and the Laboratory of Paleontology of the Universidade Regional do Cariri. The types of damage identified in this study is insect galls, leaf margin feeding (herbivory), leaf mines, oviposition of insects and skeletonization, which are present in 19 specimens. This analysis in search for evidences of plant–insect interaction contributes with new interaction patterns for the Crato Formation. Although the low sample rate, the new registers for plant-insect association were compared to records from different cretaceous basins. This suggests new possibilities in the studies for ecological relations and coevolutionary plant-insect during the Cretaceous. In addition, a new type of damage is identified in a pteridophyte.     

A new genus and species of fossil scorpion (?Euscorpiidae) from the Early–Middle Eocene of Pesciara (Bolca,Italy)

Fossil scorpions are among the oldest terrestrial arthropods known from the fossil record. They have a worldwide distribution and a rich fossil record, especially for the Paleozoic. Fossil scorpions from Mesozoic and Cenozoic deposits are usually rare (except in amber-deposits). Here, we describe the only fossil scorpion from the Early to Middle Eocene Pesciara Lagerstätte in Italy. Eoeuscorpius ceratoi gen. et sp. nov. is probably a genus and species within the family Euscorpiidae. This may be the first fossil record of the Euscorpiidae, which are so far only known from four extant genera. Eoeuscorpius ceratoi gen. et sp. nov. was found in the “Lower Part” of the Pesciara Limestone, which is actually dated Late Ypresian stage (between 49.5 and 49.7 Ma). Besides a possible pseudoscorpion, the here-described fossil scorpion is the second arachnid species known from the Bolca Locality.