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NATHALIE BARDET XABIER PEREDA SUBERBIOLA MOHAMED IAROCHENE BAADI BOUYA MBAREK AMAGHZAZ 《Zoological Journal of the Linnean Society》2005,143(3):447-472
A new species of the basal mosasaurid Halisaurus from the Late Cretaceous (Late Maastrichtian) of the Oulad Abdoun Phosphate Basin of Morocco is described on the basis of both cranial and postcranial remains. H. arambourgi sp. nov. is characterized by unique features of the nares, frontal, parietal, girdle and limb bones. A phylogenetical analysis supports the monophyletic status of Halisaurus ; H. platyspondylus (Maastrichtian, New Jersey), H. ortliebi (Maastrichtian, Belgium) and H. arambourgi form an unresolved polytomy. This study does not support the attribution of ' Halisaurus ' sternbergii (Santonian, Kansas) to Halisaurus nor to any known genus. A new genus, Eonatator , is proposed for the reception of this species, Eonatator sternbergii comb. nov. The new taxon Halisaurinae ( Halisaurus + Eonatator ) is the sister-group of more advanced mosasaurids (Natantia). Halisaurines are defined by the shape of the lateral premaxilla–maxilla suture; an oblique contact plane between the parietal and the supratemporal; a preaxial ridge present on the distal two-thirds of the radius length; and tibia and fibula long and slender with slightly expanded extremities. © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 447–472. 相似文献
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Nathalie Bardet Xabier Pereda Suberbiola Nour-Eddine Jalil 《Comptes Rendus Palevol》2003,2(8):607-616
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). 相似文献
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Abstract: A mass occurrence, numbering tens of thousands of individuals in a single lens, belonging to a single species of asteroid, is described from the late Maastrichtian (Late Cetaceous) of Morocco. The lens of partially silicified asteroidal limestone is made up largely of fully articulated specimens of similar size and probably represents the mass mortality of a single recruitment. By comparison with mass strandings of the present‐day species Asterias rubens (Linnaeus), it can be inferred that a feeding swarm of individuals was swept into a submarine channel by either a storm or an exceptionally strong tidal current, and permanently buried. The genus and species are herein described as Cretasterias reticulatus gen. et sp. nov. The exceptional preservation of the material enables the identification of wreath organs (clusters of crossed pedicellariae set in a dermal pad around spines) for the first time in the fossil record. Comparison between extant Asteriidae, putative fossil asteriids and C. reticulatus provides ambiguous evidence of its affinities; it appears to display a combination of plesiomorphic and derived characters. It is shown that all Mesozoic forcipulatid asteroids described so far share a very simple arm construction (single row of adradial ossicles) unknown in adult extant Forcipulatida. 相似文献
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《Comptes Rendus Palevol》2014,13(2):87-95
A new genus and species of huge marine turtle (superfamily Chelonioidea, epifamily Dermochelyoidae) is described from the Maastrichtian Phosphates of the Oulad Abdoun Basin of Morocco. A new type of feeding apparatus, adapted for a powerful crushing pattern, illustrates the noteworthy diversity of fossil vertebrates of the Maastrichtian-Ypresian Phosphates of Morocco. No other crushing cryptodire or bothremydid pleurodire has this morphology. During the Maastrichtian, the known crushing pattern of chelonioids was different, close to that of modern cheloniids, as illustrated in Morocco in the Maastrichtian Ganntour Basin and the Palaeogene Oulad Abdoun Basin. This new taxon exhibits unusual cranial characters (fusion of premaxillae associated with a backward and dorsal retraction of the naris, horizontal stretching of the dorsal meatus quadrati), that are shared only with another new turtle, known also from the same Maastrichtian Phosphates of Morocco. 相似文献
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VIVIAN DE BUFFRÉNIL NATHALIE BARDET XABIER PEREDA‐SUBERBIOLA BAÂDI BOUYA 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2008,41(1):59-69
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. 相似文献
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Desiree Johnson Nigel L. Hywel-Jones Joseph F. Bischoff Joseph W. Spatafora 《Mycological Research》2009,113(3):279-289
Torrubiella is a genus of arthropod-pathogenic fungi that primarily attacks spiders and scale insects. Based on the morphology of the perithecia, asci, and ascospores, it is classified in Clavicipitaceae s. lat. (Hypocreales), and is considered a close relative of Cordyceps s. 1., which was recently reclassified into three families (Clavicipitaceae s. str., Cordycipitaceae, Ophiocordycipitaceae) and four genera (Cordyceps s. str, Elaphocordyceps, Metacordyceps, and Ophiocordyceps). Torrubiella is distinguished morphologically from Cordyceps s. lat. mainly by the production of superficial perithecia and the absence of a well-developed stipitate stroma. To test and refine evolutionary hypotheses regarding the placement of Torrubiella and its relationship to Cordyceps s. lat., a multi-gene phylogeny was constructed by conducting ML and Bayesian analyses. The monophyly of Torrubiella was rejected by these analyses with species of the genus present in Clavicipitaceae, Cordycipitaceae, and Ophiocordycipitaceae, and often intermixed among species of Cordyceps s. lat. The morphological characters traditionally used to define the genus are, therefore, not phylogenetically informative, with the stipitate stromata being gained and/or lost several times among clavicipitaceous fungi. Two new genera (Conoideocrella, Orbiocrella) are proposed to accommodate two separate lineages of torrubielloid fungi in the Clavicipitaceae s. str. In addition, one species is reclassified in Cordyceps s. str. and three are reclassified in Ophiocordyceps. The phylogenetic importance of anamorphic genera, host affiliation, and stipitate stromata is discussed. 相似文献
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The material belonging to the holotype of Rayososaurus agrioensis Bonaparte is redescribed. The great development of the acromion process, directed in a markedly posterior direction, and the ventral margin of the scapula with a strong ventrodistal expansion, interpreted as autapomorphies of the taxon, justify the validity of the species. Although the material is rather fragmentary, the racquet-shaped scapula, the distal expansion positioned at the same height as the proximal expansion, and the well-developed acromion process allow the taxon to be included within Rebbachisauridae. At the same time, the angle of less than 90? between the coracoid articulation and the scapular blade, together with the great development of the acromion process of the scapula, justify its inclusion in a clade situated as a sister group of Cathartesaura. On the basis of the stratigraphic calibration of the phylogenetic analysis, an important diversification event of the rebbachisaurids is deduced during the Hauterivian-Barremian. In this context, the presence of two monophyletic groups, one of which comprises African-European taxa and the other South American taxa, would place the definitive separation of South America and Africa within this time interval. 相似文献
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Andrej ?erňanský 《Geobios》2010,43(6):605
A revision of Chamaeleo caroliquarti Moody and Ro?ek is presented. The comparisons of the holotypic left dentary with those of specimens subsequently assigned to C. caroliquarti and of the Recent species of Chamaeleo, Furcifer and Calumma is carried out. It is shown that the type dentaries of C. caroliquarti include two different morphotypes with the absence of unique features. Within the Recent chameleons, the exact determination of the individual species merely on the basis of the dentaries is impossible. The holotypic dentary of C. caroliquarti is basically identical with that of C. calyptratus. However, the same morphology of the dentary as present in C. caroliquarti is also present in other species of different genera such as Calumma globifer and Furcifer pardalis. The paratypic dentaries of C. caroliquarti have a different morphology to the holotype and are indistinguishable from that in the Recent C. chamaeleon. On the other hand, a new species of the genus Chamaeleo, C. andrusovi, is described on the basis of isolated cranial elements, which possess clear autapomorphic features. This material comes from the Lower Miocene (Ottnangian) zone MN 4 in the Dolnice locality of the Czech Republic, and it differs from Recent and fossil chameleons in the following combination of characters: (1) its typically developed strongly pustular ornamentation and its distribution on the external surfaces of the skull roofing bones; (2) the frontoparietal suture is digitiform with a well-developed, anteriorly directed mesial spine, and (3) the parietal bone narrows posteriorly at its midlength, it is not bowed dorsally and it does not contribute posteriorly to a dorsal sagittal crest. This new material expands our knowledge of the cranial anatomy of Lower Miocene chameleons. 相似文献
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Ambrosia beetles (Coleoptera: Scolytinae) are associated with strictly entomochoric and mutualistic fungi. We studied the mycobiota associated with Scolytodes unipunctatus, ambrosia beetles that infest Cecropia trees in Central America. Isolates were characterized using morphology and rDNA sequences (ITS region, LSU, and SSU rDNA). Four species are described here: Raffaelea scolytodis sp. nov. (Ophiostomatales), Gondwanamyces scolytodis sp. nov., Custingophora cecropiae sp. nov., and Graphium sp. (Microascales). The genus Custingophora is emended to include Knoxdaviesia anamorphs of Gondwanamyces based on uniformity of DNA sequences and phenotype. 相似文献
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Several large suid cranial remains attributed to Microstonyx major are part of a new Hipparion Fauna collection from the Hezheng area, Northern China. The new material confirms the presence of Microstonyx in the late Miocene of the area. The Chinese form belongs to a small-sized eastern population with reduced premolar row and clear sexual bimodality. Statistical comparison shows that Microstonyx major was a polymorphic species and reinforces recognition of Hippopotamodon as a separate genus, defined by relatively stout premolars resulting from a different underlying pattern of allometric growth. The presence of Microstonyx in North China and the distinct suid assemblage that lived there suggest biogeographic connections between Northern China and Western Eurasia in contrast to isolation from Southern China and the Indian subcontinent. The suid fauna of the late Miocene of Northern China seems to have been restricted to the later, more humid phase represented by the Red Clay faunas. 相似文献
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Fabien Knoll 《Geobios》2008,41(6):779
A review of the historical background of the material housed in the Staatliches Museum für Naturkunde (Stuttgart) and ascribed to Procompsognathus triassicus (Upper Triassic, Germany) is provided. The systematic position of the postcranial remains is discussed. The combined results of cladistic analyses suggest that the type material, an incomplete postcranial skeleton in two pieces (SMNS 12591), is from a theropod close to Segisaurus and Coelophysis. An isolated manus (SMNS 12352a) is definitely not theropodan, but could be from any small basal archosaur. The remarkable diversity of the carnivorous guild that dwelled in southern Germany before the end-Triassic events is underlined. 相似文献
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The Abildgaardieae tribe within the family Cyperaceae comprises six or seven genera, among which Abildgaardia, Bulbostylis and Fimbristylis pose a challenge regarding their morphological delimitation. Molecular phylogenetic analyses including species of Abildgaardieae are rare, but in most of those studies, Abildgaardia and Fimbristylis appear as more closely related to each other than to the Bulbostylis genus. Duration of the style base has been one of the most widely used characters for delimiting these three genera. The style base is a persistent structure in most species of Bulbostylis and deciduous in Abildgaardia and Fimbristylis. The reasons why the style base may persist or fall off have been scarcely discussed. The assumption that abscission layers are present in the style base of all three genera and the fact that tracheids have been observed in the style base of Bulbostylis suggest that this structure might have histological complexity. In view of this, a complete ontogenetic and anatomical study of the gynoecium has been carried out for all these three genera. It turned out that the style base is histologically simple in Abildgaardia, Bulbostylis and Fimbristylis and shows similar structure and development in all three genera. The fact that the style base has a shorter duration in Abildgaardia and Fimbristylis than in Bulbostylis might be related to the lower number of sclerotised cells that make up such structures in the mature fruit of the former two genera. Abscission of the style and style base may be the result of much simpler reasons than the differentiation of an abscission layer, resulting merely from mechanical shear force effects. Differences among genera have been observed in the shape of the style base and the development of the style. The histological simplicity of the style base is consistent with the homoplastic appearance of this structure in genera that are not closely related (e.g. Rhynchospora). Because of this, while the presence of the thickened style base seems to be a synapomorphy in species of Abildgaardieae, its persistence on or detachment from the fruit might have emerged repeatedly during this clade evolution and might not be a suitable character for genera delimitation. 相似文献
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Hyaloscyphaceae is the largest family in Helotiales, Leotiomycetes. It is mainly characterized by minute apothecia with well-differentiated hairs, but its taxonomic delimitation and infrafamilial classification remain ambiguous. This study performed molecular phylogenetic analyses using multiple genes including the ITS-5.8S rDNA, the D1–D2 region of large subunit of rDNA, RNA polymerase II subunit 2, and the mitochondrial small subunit. The primary objective was to evaluate the phylogenetic utility of morphological characters traditionally used in the taxonomy of Hyaloscyphaceae through reassessment of the monophyly of this family and its genera. The phylogenetic analyses inferred Hyaloscyphaceae as being a heterogeneous assemblage of a diverse group of fungi and not supported as monophyletic. Among the three tribes of Hyaloscyphaceae only Lachneae formed a monophyletic lineage. The presence of hairs is rejected as a synapomorphy, since morphologically diversified hairs have originated independently during the evolution of Helotiales. The true- and false-subiculum in Arachnopezizeae are hypothesized to have evolved through different evolutionary processes; the true-subiculum is likely the product of a single evolutionary origin, while the false-subiculum is hypothesized to have originated multiple times. Since Hyaloscyphaceae sensu lato was not resolved as monophyletic, Hyaloscyphaceae sensu stricto is redefined and only applied to the genus Hyaloscypha. 相似文献
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An increase in clinical cases of Candidiosis globally as well as fungal resistance to drugs prompted the search for novel anti-Candida albicans agents from plant sources. Leaf extracts of Markhamia obtusifolia were screened for activity against C. albicans in vitro. An acetone extract obtained following serial exhaustive extraction contained mainly the active components with at least four active zones on the bioautogram. Bioassay guided fractionation of this extract led to the isolation of three compounds which inhibited the growth of three C. albicans strains. Based on spectroscopy studies (NMR and MS), the compounds were identified as 3β-hydroxyurs-12-en-28-oic acid, ursolic acid (1) 3β, 19α-dihydroxyurs-12-en-28-oic acid, pomolic acid (2) and 2β, 3β, 19α -trihydroxy-urs-12-en-28-oic acid, 2-epi-tormentic acid (3). The most active compound was 3β, 19α-dihydroxy-12-ursen-28-oic acid (2) with a minimum inhibitory concentration (MIC) value of 12.5 µg/mL for C. albicans isolated from dog and 25.0 µg/mL for C. albicans from cat and ATCC 90028 at 24 h following incubation. However, at 48 h of incubation MICs were > 400 µg/mL for all the three compounds isolated. This study indicated that M. obtusifolia could be a potential source of active principles against C. albicans. 相似文献
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Kenneth G.A. van Driel Bruno M. Humbel Joost Stalpers Teun Boekhout 《Mycological Research》2009,113(5):559-576
The ultrastructure of septa and septum-associated septal pore caps are important taxonomic markers in the Agaricomycotina (Basidiomycota, Fungi). The septal pore caps covering the typical basidiomycetous dolipore septum are divided into three main phenotypically recognized morphotypes: vesicular-tubular (including the vesicular, sacculate, tubular, ampulliform, and globular morphotypes), imperforate, and perforate. Until recently, the septal pore cap-type reflected the higher-order relationships within the Agaricomycotina. However, the new classification of Fungi resulted in many changes including revision of existing and addition of new orders. Therefore, the septal pore cap ultrastructure of more than 325 species as reported in literature was related to this new classification. In addition, the septal pore cap ultrastructures of Rickenella fibula and Cantharellus formosus were examined by transmission electron microscopy. Both fungi have dolipore septa associated with perforate septal pore caps. These results combined with data from the literature show that the septal pore cap-type within orders of the Agaricomycotina is generally monomorphic, except for the Cantharellales and Hymenochaetales.It appears from the fungal phylogeny combined with the septal pore cap ultrastructure that the vesicular-tubular and the imperforate type both may have arisen from endoplasmic reticulum. Thereafter, the imperforate type eventually gave rise to the perforate septal pore cap-type. 相似文献