Specialization of bone structure in Pachyvaranus crassispondylus Arambourg, 1952, an aquatic squamate from the Late Cretaceous of the southern Tethyan margin

The histological organization of the vertebrae of the Maastrichtian squamate Pachyvaranus crassispondylus Arambourg, 1952 , was compared to that of various extant squamates, in order to further document the causes and functional consequences of the so-called 'pachyostosis', frequently observed in Late Cretaceous squamates. The vertebrae of Pachyvaranus are composed of the same basic bone tissue types as those of extant lizards and snakes. In particular, periosteal cortices are made of a pseudolamellar (or 'parallel-fibred') tissue, with radial vascular canals, Sharpey's fibres and conspicuous cyclic growth marks that are strictly identical to that found in extant varanids. Conversely, the vertebrae of Pachyvaranus are extremely compact, whereas those of extant squamates are very cancellous and lightly built. This difference is due to the absence in Pachyvaranus of a broad internal resorption field that, in extant lizards and snakes, transforms compact cortices into loose spongy formations. This absence of inner bone resorption typically corresponds to an osteosclerotic process. In Pachyvaranus , cortical hyperplasy, or pachyostosis stricto sensu , was restricted to the walls of the neural spine. Extreme vertebral porosity is likely to be a primitive condition in squamates, because all lizards and snakes examined in this study display this feature. Therefore, the high vertebral compactness observed in Pachyvaranus would be a derived condition arising from the loss (or de-differentiation) of a morphogenetic process: the broad internal resorption of the vertebrae. Possible palaeoecological bearings of these results are discussed.     

A new anatomically preserved ginkgoalean genus from the Upper Cretaceous (Cenomanian) of the Czech Republic

A new genus of ginkgoalean woody branch, Pecínovicladus kvaceki gen. et sp. nov., is described from the Upper Cretaceous (mid to late Cenomanian) Peruc-Korycany Formation at Pecínov Quarry, near Prague, Czech Republic. Eighteen branch specimens, anatomically preserved as charcoal, the product of wildfire, occur as allochthonous assemblages in intertidal facies and as parauthochthonous assemblages in supratidal salt marsh facies. Primary branches range from 7–13 mm in diameter, and are composed of a central, parenchymatous pith, a medial pycnoxylic xylem layer, and an outer periderm layer. Closely spaced, helically arranged leaf bases and rare secondary branch scars characterize the exterior. The branches are confidently referred to the Ginkgoales on the basis of a variety of diagnostic xylem features, most notably the presence of inflated axial parenchyma containing moulds of crystals, and by the precise anatomical correspondence of the leaf bases to those of detached, but facies-associated Nehvizdya obtusa leaves of known ginkgoalean affinity. The newly described ginkgoalean, together with cheirolepidiaceous conifers, formed fire-prone vegetation in halophytic salt marsh environments under a seasonal, subtropical climate.     

A mosasaur from the Cenomanian of Russia

The premaxilla of a mosasauroid lizard from the Lysaya Gora 3 locality in Saratov (Upper Cretaceous, Cenomanian) is described. To date, the oldest known mosasaur remains have been dated Turonian. The premaxilla is most similar in morphology to that of Russellosaurus from the Turonian of the United States; however, the absence of sufficient diagnostic characters only allows its attribution to Mosasauridae indet.     

Comparative biology and the importance of cladistic classification: a case study from the sensory biology of squamate reptiles

Evolutionary taxonomy has all but succumbed to cladistic methodology, but it continues to exert considerable influence in the realm of higher classification. Some systematists accept cladistic methods in phylogeny inference, but allow paraphyly in formal classifications. Most important, however, many traditional classifications based on paraphyletic groups (e.g. 'Reptilia') remain in force, deeply entrenched in the literature. Cladists have argued that such paraphyletic classifications can mislead comparative biologists into false evolutionary generalizations, but this assertion has rarely, if ever, been supported by example. This paper provides a case study, illustrating in detail the influence of a traditional paraphyletic classification of squamate reptiles on the historical development of ideas regarding the evolution of sensory modes (chemoreception vs. vision) in the group. The paraphyletic classification is shown to have led to false generalizations and incorrect conclusions stemming directly from the fact that the classification did not reflect accurately the phylogeny of Squamata, particularly the cladistic relationships of Gekkota. This study provides direct evidence that evolutionary generalization must be rooted in the branching pattern of phylogeny and not the potentially arbitrary categorical ranks of traditional taxonomies. It further supports recent calls for a truly phylogenctic taxonomy that has as its philosophical core the concept of descent.     

Species of the water-fern megaspore genus Molaspora from a Cenomanian deposit in western France: occurrence,sporoderm ultrastructure and evolutionary relationships

The partially reticulate sculpture of Molaspora aspera sp. nov., a marsileaceous megaspore from a Cenomanian deposit in western France, distinguishes it from other species of Molaspora. An acrolamella entirely surrounds and obscures a small tetrad scar, a feature that has been demonstrated hitherto within members of the genus only in M. fibrosa. It was also encountered for the first time in M. lobata, with which the new species is associated in the same French mesofossil assemblage. The ultrastructure of the sporoderm of M. aspera is similar to that of M. lobata, but differs particularly in that the inner epispore is markedly thicker and may also contain numerous large, homogeneous spherules or, alternatively, holes of comparable dimensions and only a few small spherules. It is possible that these are a response to some hostile bacterial or other activity when the developing sporoderm was partially permeable. The cavity replacing part of the epispore in one of the specimens, and in the specimen of M. lobata examined, may be a preservational feature or have served to increase buoyancy of the spore in water. Molaspora lobata is very similar to megaspores of fossil and extant Regnellidium, but M. aspera bears some resemblance to other members of extant Marsileaceae and certain species of Cretaceous Arcellites, although there are significant differences between them. This suggests that Molaspora is a heterogeneous taxon embracing megaspores produced by water ferns of more than one natural genus, of which only Regnellidium has survived to the present day.     

Comparative morphology of the dermal palate in squamate reptiles, with comments on phylogenetic implications

The differentiation of the dermal palate and of the septomaxilla in extant squamate reptiles is reviewed in terms of Lakjer's distinctions of a palaeochoanate, incomplete neochoanate, and neochoanate condition. The differentiation of the bones surrounding the mushroom body, Jacobson's organ, and the internal naris (choana) supports a number of clades including Squamata, Scleroglossa, and Autarchoglossa, with Serpentes nested within Autarchoglossa. Dermal palate morphology and the differentiation of the septomaxilla in squamates reflect the evolution of the chemosensory system in general, and the vomeronasal system in particular, and strongly contradict a recent hypothesis of squamate phylogeny based on molecular data.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 152 , 131–152.     

白垩纪中期克钦琥珀毛蚊科(双翅目:毛蚊总科)昆虫一新属新种

毛蚊科是双翅目长角亚目的一类昆虫,其种类丰富,广布世界各地.毛蚊化石记录较为丰富,但往往都是保存于湖相沉积地层中,琥珀中的化石较为罕见.本文根据缅甸北部克钦地区产出的白垩纪中期琥珀中保存的昆虫标本建立了 1新属新种——缅甸白垩叉毛蚊(Cretpenthetria burmensis gen.et sp.nov.),归入...     

山东半岛北部沿岸岛屿蝮属一新种(爬行纲,有鳞目,蝰科)

根据对山东半岛沿岸岛屿上的13号蝮蛇标本(7♂♂,6♀♀)外部形态的详细观察,并与同属其他各种比较,均有不同,应为亚洲蝮属1新种.新种的鉴别特征:1)中段背鳞23行;2)腹鳞+尾下鳞187～198,平均191行;3)体棕褐色,背部有两行粗大、周围暗棕色而中心色浅、外侧开放的圆斑,左右圆斑彼此交错或并列;4)眶后有一较宽黑色眉纹,其下缘略呈波状且镶有一条明显的白色细纹.     

A new lizard-like reptile (Diapsida: Lepidosauromorpha) from the Middle Jurassic of England

The Middle Jurassic (Late Bathonian) Mammal Bed at Kirtlington, Oxfordshire, has yielded a rich assemblage of small vertebrates including mammals, frogs, salamanders and small reptiles. This paper describes the skull of a new diapsid reptile, Marmorelta oxoniensis, which was common within the fauna. The skull is gracile with large orbits and relatively long external nares. The frontals and parietals are single in the adult and almost separated on the roof of the skull by the postfrontals. The temporal region shows a mosaic of primitive and derived character states. The quadrate was firmly held to the skull by a large squamosal and a small, free, quadratojugal was retained. However, reduction of the anterior process of the quadratojugal and of the posterior process of the jugal left the lower temporal fenestra broadly open. Comparison with other diapsids leads to the conclusion that Marmoretta was a lepidosauromorph, most probably the sister taxon of Lepidosauria.     

A new mosasauroid (Squamata) from the Late Cretaceous (Turonian) of Morocco

Tethysaurus nopcsai gen. et sp. nov. is described on the basis of both cranial and postcranial material from the Late Cretaceous (Early Turonian) of the Goulmima region, southern Morocco. This new mosasauroid is mainly characterized by a parietal table ending posteriorly in two pointed pegs; jugal with a large ascending ramus; splenial with a large and notched dorsomedial process; surangular exposed medially ventral to the coronoid; large paracotylar and parazygosphenal foramina on vertebrae. A phylogenetic analysis shows that Tethysaurus is the sister-group of Mosasauridae. It fills the gap between the aigialosaurids (mainly Cenomanian) and the mosasaurids (known from the Middle-Late Turonian to the Latest Maastrichtian). To cite this article: N. Bardet et al., C. R. Palevol 2 (2003).     

Plant inclusions from the Cenomanian flints of Archingeay,Les Nouillers,western France

Here, we report flint nodules bearing fossil plant inclusions from the early Cenomanian of the Font‐de‐Benon sand quarry, between the villages of Archingeay and Les Nouillers, Charente‐Maritime, western France. The broken‐open surfaces of these dense siliceous rocks only partly show the whole diversity, which is established using a non‐destructive, multi‐scale approach based on propagation phase‐contrast X‐ray synchrotron microtomography. The conifer genera Brachyphyllum, Frenelopsis, Geinitzia, and Glenrosa have three‐dimensional preservation, and vegetative and reproductive organs are in connection in some cases. The flint nodules formed by silicification of Cenomanian sediments, probably as a result of an intensive period of soil alteration and leaching under warm and wet climate during the Eocene. Although the time was long between the Cenomanian sedimentation and the Eocene silicification, the fossil plants show three‐dimensional external morphology. These mineralizations are interpreted as fine silica microcrystallization over the cell walls and thus are examples of late silica permineralization. The association of foraminifers, echinoids, sponge spicules, and conifers suggests that the Cenomanian sediments were deposited in a coastal and open to the sea palaeoenvironment, near a conifer‐dominated mangrove.     

A new species of Thecadactylus from Sint Maarten, Lesser Antilles (Reptilia, Squamata, Gekkonidae)

We describe a new species of Thecadactylusfrom the Caribbean island of Sint Maarten. The new species differs from all other species in the genus by having a distinct dorsal pattern of numerous irregular but sharply deliminated black spots and blotches on an otherwise almost patternless background.     

The Cenomanian of northern Germany: facies analysis of a transgressive biosedimentary system

A facies analysis of the epicontinental marine Cenomanian sediments of northern Germany shows the presence of 17 facies types (FTs, including several subtypes) which can be assigned to three facies associations: 1) an inner shelf facies association (FT 1–8) with high amounts of terrigenous material and/or high-energy depositional features, 2) a middle shelf facies association (FT 9–15) of predominantly calcareous sediments with moderate amounts of generally fine siliciclastics, and 3) an outer shelf facies association (FT 16–17) of low-energy, fine-grained, pure limestones. These three facies associations roughly correspond to the well-known lithological units of the Cenomanian of northern Germany, i.e., the Essen Greensand/Cenomanian Marls complex, the Pläner Limestones, and the Poor rhotomagense Limestones. The sediments were deposited on a northward-dipping homoclinal ramp with more-or-less shoreline-parallel facies belts. The sediment composition on this ramp-like shelf was a function of the varying importance of three different sediment sources: 1) terrigenous input from the south (Rhenobohemia), generally fining/decreasing in a proximal–distal (i.e., S–N) direction; 2) production of skeletal grains, mainly by macrobenthic organisms; and 3) settling of planktic carbonate (mainly calcispheres and calcareous nannofossils). In response to decreasing water energy with increasing water depth, the seaward decreasing terrigenous influence, and increasing planktic carbonate production, increasingly finer and more calcareous sediments were deposited in a proximal–distal transect. This rather straightforward picture was slightly modified by highest carbonate accumulation rates (planktic and benthic) on the middle shelf, forming a mid-shelf depocenter (fossiliferous, calcisphere-rich Pläner Limestones). Time-transgressive, southward-directed onlap of this biosedimentary system during the Cenomanian caused a significant retreat of the coastline towards the south and a retrogradational stacking of facies belts, explaining the broadly similar facies development and lithology of Cenomanian successions across northern Germany. The boundaries of the lithological units, however, tend to be considerably diachronous in a distal–proximal transect. In the late Middle and early Late Cenomanian, a final drowning and facies levelling (“oceanization”) is indicated by the widespread deposition of uniform calcareous nannofossil mudstones (Poor rhotomagense Limestones).     

Plant-dominated assemblage and invertebrates from the Lower Cenomanian of Jaunay-Clan,western France

Two fossil localities are reported on the “LGV SEA” railroad from the Lower Cenomanian of Jaunay-Clan (JC), near Poitiers, western France. The laminated mudstones yielded plant fossils including ferns (Cladophlebis, Osmundophyllum, Ruffordia goeppertii, Sphenopteris), conifers (Brachyphyllum, Dammarophyllum, Pagiophyllum), and terrestrial and aquatic freshwater angiosperms (Eucalyptolaurus depreii, Ploufolia). They are associated with a coleopteran insect that shows systematic affinities to the modern subfamily Chrysomelinae (Chrysomelidae). This assemblage suggests connections with arborescent vegetation growing in calm freshwater environment. Brackish to marine invertebrates also occur and include a dakoticancroid crab (Brachyura, Podotremata, Dakoticancroidea) and a few bivalves (Brachidontes). They suggest brackish episodes during pond sedimentation in a coastal environment. Lastly, vertebrates are represented by an isolated feather.     

中国柄锈菌属一新种和酸模柄锈菌一新变种（英文）

报道了产自中国内蒙古的柄锈菌属1新种和1新变种。糙苏Phlomis umbrosa上的糙苏生柄锈菌Puccinia phlomidicola为新种;直根酸模Rumex thyrsiflorus上的酸模柄锈菌直根酸模变种Puccinia acetosae var.thyrsiflori为新变种。提供了详细的形态描述和线条图。研究标本保存在赤峰学院菌物标本室(CFSZ)和中国科学院菌物标本馆(HMAS)。     

A two-headed reptile from the Cretaceous of China

A malformed embryonic or neonate choristoderan reptile from the Lower Cretaceous Yixian Formation of northeastern China is described. The tiny skeleton exhibits two heads and two necks, with bifurcation at the level of the pectoral girdle. In a fossil, this is the first occurrence of the malformation known as axial bifurcation, which is well known in living reptiles.     

The skull and the palaeoecological significance of Labidosaurus hamatus, a captorhinid reptile from the Lower Permian of Texas

The cranial skeleton of the large captorhinid reptile Labidosaurus hamatus , known only from the Lower Permian of Texas, is described on the basis of new, undescribed specimens. Labidosaurus is distinguished from other captorhinids by the more extreme sloping of the ventral (alveolar) margin of the premaxilla, a low dorsum sellae of the parabasisphenoid, a reduced prootic, a narrow stapes, and a relatively small foramen intermandibularis medius. Despite the presence of a single row of teeth in each jaw, the skull of Labidosaurus resembles most closely those of moradisaurines, the large multiple-tooth-rowed captorhinids of the latest Early and Middle Permian. A phylogenetic analysis confirms that the single-tooth-rowed L. hamatus is related most closely to moradisaurines within Captorhinidae, a relationship that supports the hypothesis of a diphyletic origin for multiple rows of marginal teeth in captorhinids (in the genus Captorhinus and in the clade Moradisaurinae). In view of the close relationship between L. hamatus and moradisaurines, which are regarded to have been herbivorous, L. hamatus is a critical taxon for studies of the evolution of herbivory in early tetrapods. L. hamatus shares several trademark features of herbivorous adaptation with moradisaurines, which suggest that this captorhinid species was omnivorous. As such, it represents a transitional taxon between faunivorous basal reptiles and the herbivorous moradisaurines.  © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 149 , 237–262.     

Cenomanian cheilostome bryozoans from Devon,England

The Cenomanian witnessed a spectacular evolutionary radiation of cheilostome bryozoans, both in terms of species diversity and morphological disparity. However, Cenomanian cheilostome faunas are inadequately known. Twelve species of cheilostome bryozoans are here described from the Cenomanian Beer Head Limestone Formation of SE Devon, England, a nearshore facies of limestones and sands. Two of the cheilostome species are new – Wilbertopora manubriformis sp. nov. and Foratella cervisia sp. nov. – and five cannot be identified beyond genus level. Syntypes of Foratella forata (d’Orbigny, 1853), the Senonian type species of Foratella Canu, 1900, are illustrated using SEM and a lectotype is chosen. All of the species present are neocheilostomes, which were larval brooders. Compared with the non-brooding malacostegans that dominate pre-Cenomanian faunas, most species have avicularia and extensive frontal walls, features probably adaptive against small predators.