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《Review of Palaeobotany and Palynology》2005,133(3-4):169-178
We describe here fossil leaves and fruits assignable to the family Nelumbonaceae Dumortier 1828. Fossils were collected at the Cañadón del Irupé locality, La Colonia Formation (Campanian–Maastrichtian, Upper Cretaceous), Chubut Province, Patagonia, Argentina. The fossil leaves are simple, with symmetrical and peltate lamina, orbicular in shape, and an entire margin. The venation is truly actinodromous with at least 15 primary veins, the secondary veins are poorly developed and intercalated with the primary veins, the third category vein is opposite, and the areoles are well-developed and 4- to 5-sided. These features are characteristic of the extant genus Nelumbo Adamson 1763, and the presence of these characters in the fossils allows their placement within this genus. Reproductive structures, similar to the fruit-receptacle of Nelumbo with fruits in situ, were found associated but not in organic connection with the leaves. These fossils constitute the only and oldest record for the family in the Southern Hemisphere. This record indicates that Nelumbo was more widespread in the past than today. 相似文献
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ENRIC VICENS 《Palaeontology》2012,55(2):325-339
Abstract: A new type of small, ovoid dinosaur egg, Sankofa pyrenaica oogen. nov. oosp. nov., with a prismatic type eggshell is described from upper Cretaceous (upper Campanian–Maastrichtian) deposits of the Montsec area, South Pyrenean Central Unit, Lleida, Catalonia, Spain. This egg type was sub‐vertically laid in only two rich monospecific sites of a single stratigraphic layer from coastal deposits of the Aren Formation, interpreted as an emerged beach ridge of a barrier island – lagoon depositional system. The size and shape of these eggs with their asymmetric poles are roughly similar to modern hen eggs, which is unusual in the Cretaceous fossil egg record. Its phylogenetic position clusters with bird and Troodontid eggs. A morphospace analysis of egg shapes shows the similarity of the new egg to a Campanian fossil bird egg from Argentina, both being intermediate between modern‐bird eggs and extinct nonavian theropod eggs. However, the eggshell microstructure of Sankofa pyrenaica differs from that of bird eggs in its incipient squamatic texture. It has a peculiar pattern of interlocking small crystals in the middle of the palisade layer, instead of the thick squamatic structure commonly present in modern avian eggshells. This new egg type is attributed to a small theropod, probably with a single oviduct like birds and whose mosaic distribution of features is a combination between that of birds and nonavian theropods. This enhances the arguments supporting the close phylogenetic relationships between both groups. 相似文献
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CARLOS E. M. OLIVEIRA RODRIGO M. SANTUCCI MARCO B. ANDRADE VICENTE J. FULFARO JOSÉ A. F. BASÍLIO MICHAEL J. BENTON 《Palaeontology》2011,54(2):309-321
Abstract: Compared with crocodylomorph body fossils, the record of fossil crocodiloid eggs is scarce and poorly understood, a gap partially attributed to their typically thin eggshell, which is not conducive to preservation. A remarkable new association of well‐preserved eggs and eggshells from the Adamantina Formation (Bauru Group, Upper Cretaceous) is described and compared to other known materials, while the significance of their unique oological features is discussed. These eggs constitute a new ootaxon, Bauruoolithus fragilis oogen. et oosp. nov., diagnosed by the following characteristics: elongate and elliptical egg with blunt ends; length‐to‐diameter ratio of 1:0.55; outer surface slightly undulating; shell thickness ranging from 0.15 to 0.25 mm; pore openings elliptical or teardrop‐shaped, ranging from 30 to 80 μm in diameter; and shell units wider than higher, with the interstices forming an obtuse triangle. Specimens of Bauruoolithus also show only slight signs of extrinsic degradation that, coupled with the evidence that some of them constitute hatched eggs, suggests that the egg‐laying taxon had a different pattern of egg incubation, in which the hatchling could break through the rather thin eggshell relatively easily and that the extrinsic degradation of the eggshell was not necessary. This contrasts with the pattern of incubation for all other known crocodylomorphs and crocodiloid eggs, where extrinsic degradation is a key component of the hatching process. 相似文献
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Luc te Marvelde Simone L. Webber Arnold B. van den Burg Marcel E. Visser 《Journal of Field Ornithology》2011,82(3):320-324
ABSTRACT The physiological condition of female birds during the egg‐laying and incubation periods is of considerable interest and yet is relatively understudied in wild birds, primarily due to the difficulty of catching birds during this period without causing nest desertion. We therefore developed a box‐net to capture cavity‐nesting birds using sections of a mist‐net placed around a metal cubic frame. We captured female Great Tits (Parus major) as they left nest boxes during the egg‐laying and incubation periods and measured desertion rates. Using box‐nets, we captured 108 of 119 (90%) females during egg laying and 10 of 12 (83%) during incubation. Our recapture rate over two consecutive days during incubation was 50% (5 of 10). Females not captured left nest boxes before we attempted to capture them, escaped through a hole in the mist‐net, or remained in nest boxes for more than 2 h, after which we ended capture attempts. Overall, 22% of egg‐laying females deserted, with desertion rates highest early in the egg‐laying period. Desertion rates of females captured using box‐nets did not differ from those of undisturbed females. One of 10 females captured in a box‐net deserted during the incubation period. Box‐nets are portable, can be set up and taken down quickly and easily, and could potentially be used with nest boxes or natural cavities at any height. Box‐nets are easy to construct and adaptable for use with an array of cavity‐nesting birds, and can be an important tool for studying female physiology during egg laying and incubation. 相似文献
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A new baurusuchid, Wargosuchus australis gen. et sp. nov., coming from the Bajo de La Carpa Formation, Neuquén Province (Argentina), is described. This new taxon is based on a fragment of snout and a portion of the cranial roof. Wargosuchus differs from other crocodyliforms by possessing a deep median groove on the frontals, a contact between nasals and frontals extremely reduced, a large depression for the olfactory bulbs, three large foramina surrounding the large, smooth perinarial depression, and a hypertrophied, conical last premaxillary tooth followed by a large paracanine fossa. The finding of Wargosuchus in Patagonia (Argentina), a taxon with a strong resemblance to Brazilian baurusuchids, reinforces the hypothesis of a similar biota between both regions by the Late Cretaceous. Wargosuchus and Cynodontosuchus represent the only Argentinian mesoeucrocodylians to be included within Baurusuchidae. This finding extends the number of crocodyliforms from the Bajo de la Carpa Formation, which, in turn, corresponds to the most taxonomically diverse one in Argentina. 相似文献
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Background
The ceratopsians represent one of the last dinosaurian radiations. Traditionally the only universally accepted speciose clade within the group was the Ceratopsidae. However, recent discoveries and phylogenetic analyses have led to the recognition of a new speciose clade, the Leptoceratopsidae, which is predominantly known from the Upper Cretaceous of North America.Methodology/Principal Findings
Here we report a new leptoceratopsid taxon, Zhuchengceratops inexpectus gen. et sp. nov., based on a partial, articulated skeleton recovered from the Upper Cretaceous Wangshi Group of Zhucheng, Shandong Province, China. Although Zhuchengceratops is significantly different from other known leptoceratopsids, it is recovered as a derived member of the group by our phylogenetic analysis. Furthermore, Zhuchengceratops exhibits several features previously unknown in leptoceratopsids but seen in ceratopsids and their close relatives, suggesting that the distribution of morphological features within ceratopsians is more complex than previously realized.Conclusion/Significance
The discovery of Zhuchengceratops increases both the taxonomic diversity and the morphological disparity of the Leptoceratopsidae, providing further support for the hypothesis that this clade represents a successful radiation of horned dinosaurs in parallel with the Ceratopsidae in the Late Cretaceous. This documents a surprising case of the coexistence and radiation of two closely-related lineages with contrasting suites of jaw and dental features that probably reflect adaptation to different food resources. 相似文献9.
记述了一件发现于内蒙古临河巴彦满达呼上白垩统乌兰苏海组的窃蛋龙科新材料并建立了一新属新种——戈壁乌拉特龙(Wulatelong gobiensis gen. et sp. nov.)。新属种具有以下不同于其他窃蛋龙科成员的独特特征:外鼻孔大而细长,腹端低于前上颌骨中部;上颌骨的颧骨支呈带状,并向后延伸至眶前隔之后,叠覆于颧骨外侧面;外侧视,上隅骨的前背突基部收缩。戈壁乌拉特龙具有一些其他窃蛋龙科成员不具有的近祖特征,而与更原始的窃蛋龙类接近,说明戈壁乌拉特龙代表了窃蛋龙科中一个相对原始的属种。这些近祖特征包括:下颞颥孔的背缘较窄,泪骨的前突和后突相对较长,外翼骨和外下颌孔的位置都相对靠后,肩胛骨短而纤细,肠骨的耻骨茎较坐骨茎向腹侧延伸更长并前后向更宽,坐骨较短,以及第三跖骨近端侧扁等。因此戈壁乌拉特龙的系统发育位置可能居于原始窃蛋龙类和其他窃蛋龙科成员之间。对巴彦满达呼恐龙动物群的初步分析支持巴彦满达呼红层代表了蒙古高原戈壁地区上白垩统红层中的最早沉积层位的结论。 相似文献
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W. M. Wouts 《New Zealand journal of zoology.》2013,40(3):213-216
The first paragraph of the Introduction serves as an Abstract. Specimens of an undescribed subfamily of Tylodoridae Paramonov, 1967 were found in each of 50 soil samples collected since 1951 from around the roots of native plants on Campbell Island, New Zealand. This taxon, Campbellenchinae n.subfam., its type‐genus, Campbellenchus n.gen., and 2 new species, C. poae and C. filicauda, are described. The diagnostic characters of the new subfamily include a lip region without a labial disc, a stylet of moderate length, a characteristic zone of cuticular annulation anterior to the stylet knobs, a slit‐like amphidial opening, a single ovary, and a filiform tail. 相似文献
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A new and phylogenetically suggestive morphotype ofKeratella lenzi (Rotifer,Monogononta), from Argentina 总被引:1,自引:1,他引:0
María Cristina Marinone 《Hydrobiologia》1995,299(3):249-257
The morphological characteristics ofKeratella lenzi (f.ayui) f. nov. and the phylogenetic and ecological implications of the appearance of posterolateral spines inK. lenzi Hauer, 1953 are discussed. The morphotype is described after detailed observations using light and scanning electron microscopy, and compared with otherKeratella species of the superspecies valga. The pores of the lateral antennae are described, and proposed as a new character for future comparative research. Some ecological information is also given. 相似文献
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A new egg is described from the Upper Cretaceous lacustrine deposit of the Chichengshan Formation in the Tiantai Basin, Zhejiang Province, southeast China. The new specimen shares eggshell micro-features with members of the oofamily Stalicoolithidae, Paraspheroolithus of the oofamily Spheroolithidae and Mosaicoolithus (oofamily indet.), with barrel-shaped cones, prolatocanaliculate pore system, horizontal accretion lines and light stripes throughout the eggshell. However, the new egg differs from the aforementioned ootaxa by its small size and asymmetrical shape, revealing new morphological variation among eggs with microstructure similar to that of Paraspheroolithus, Mosaicoolithus and Stalicoolithidae. We refer the new egg to a new oogenus and oospecies, thus increasing the diversity of the Tiantai Basin oofauna. The Tiantai Basin has yielded a variety of dinosaur eggs and one turtle clutch. Comparatively, the new egg is surprisingly small and ovoid, a morphology usually associated with avian eggs, although the absence of a squamatic layer excludes the egg from being referred to this group. 相似文献
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Herrerasauridae comprises a basal clade of dinosaurs best known from the Upper Triassic of Argentina and Brazil, which have yielded remains of Herrerasaurus ischigualastensis and Staurikosaurus pricei, respectively. Systematic opinion regarding the position of Herrerasauridae at the base of Dinosauria has varied. Here we describe a new herrerasaurid, Sanjuansaurus gordilloi gen. n., sp. n., based on a partial skeleton from Carnian-age strata of the the Upper Triassic Ischigualasto Formation of northwestern Argentina. The new taxon is diagnosed by numerous features, including long, band-shaped and posterolaterally oriented transverse process on the posterior cervical vertebrae; neural spines of the sixth to eighth dorsal vertebrae, at least, bearing acute anterior and posterior processes; scapula and coracoid with everted lateral margins of the glenoid; and short pubis (63% of the femoral length). Phylogenetic analysis placed Sanjuansaurus within a monophyletic Herrerasauridae, at the base of Theropoda and including Herrerasaurus and Staurikosaurus. The presence of Sanjuansaurus at the base of the Ischigualasto Formation, along with other dinosaurs such as Herrerasaurus, Eoraptor, Panphagia, and Chromogisaurus suggests that saurischian dinosaurs in southwestern Pangea were already widely diversified by the late Carnian rather than increasing in diversity across the Carnian-Norian boundary. 相似文献
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Howard J. Falcon-Lang 《Palaeontology》2004,47(2):349-366
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. 相似文献
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A fossil scorpion belonging to a new family, genus and species, Chaerilobuthus complexus gen. n., sp. n., is described from Cretaceous amber of Myanmar (Burma). This is the third species and the fourth scorpion specimen to have been found and described from Burmese amber. The new family seems quite distinct from the family Archaeobuthidae Lourenço, 2001 described from Cretaceous amber of Lebanon. 相似文献
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Victoria M. Arbour Michael E. Burns Robert M. Sullivan Spencer G. Lucas Amanda K. Cantrell Joshua Fry Thomas L. Suazo 《PloS one》2014,9(9)
A new ankylosaurid (Ankylosauria: Dinosauria), Ziapelta sanjuanensis, gen. et sp. nov., is based on a complete skull, an incomplete first cervical half ring, a possible fragment of the second cervical half ring, and additional fragmentary osteoderms. The holotype specimen is from the Upper Cretaceous (Upper Campanian, Kirtlandian Land-Vertebrate Age) Kirtland Formation (De-na-zin Member) at Hunter Wash, San Juan Basin, in northwestern New Mexico, USA. Diagnostic characters of Ziapelta include: a large, prominent triangular median nasal caputegulum; a mixture of flat and bulbous frontonasal caputegulae; ventrolaterally oriented squamosal horns with a sharp, prominent dorsal keel; and the ventral surface of basicranium with three prominent anteroposteriorly oriented fossae. A phylogenetic analysis suggests that Ziapelta is not closely related to the other ankylosaurid from the De-na-zin Member, Nodocephalosaurus, but allies it to the northern North American ankylosaurids Ankylosaurus, Anodontosaurus, Euoplocephalus, Dyoplosaurus, and Scolosaurus. 相似文献
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A new species of Bucklandia is described based on a permineralized fossil trunk that was obtained from sediments of Upper Cretaceous age from Hokkaido, Japan. The quality of preservation is exquisite, and anatomical and morphological features are preserved at the cellular level. The specimen is clearly bennettitalean because of the cycadeoidean-type arrangement of vascular bundles in the petiole. However, this specimen is unique among previously described progymnosperms and gymnosperms in possessing a unilacunar five-trace type of nodal structure. The fossil thus contributes to a more complete understanding of the variation of nodal structure in bennettitalean trunks. 相似文献
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Abstract: A new oviraptorid is described on the basis of a partial forelimb collected from the Upper Cretaceous redbeds of Bayan Mandahu, Inner Mongolia. Machairasaurus leptonychus, gen. et sp. nov. is diagnosed by slender, weakly curved manual unguals, reduced flexor tubercles, penultimate phalanges that are subequal in length to the preceding phalanges, and short, robust manual digits. Machairasaurus is found to be a member of the Ingeniinae, along with Ingenia yanshini, Heyuannia huangi, Conchoraptor gracilis, and Nemegtomaia barsboldi. Machairasaurus exhibits unusual proportions of the manus, suggesting that the manus was not primarily used to grasp prey. Instead, Machairasaurus and other oviraptorids are likely to have fed largely on plant material. The recognition of a previously unknown oviraptorid at Bayan Mandahu provides further evidence that the Bayan Mandahu dinosaur assemblage is distinct from that found at the Djadokhta Formation exposures at Bayn Dzak, Tugriken Shireh, and Ukhaa Tolgod. Given that these localities are separated by just a few hundred kilometres and represent similar palaeoenvironments, marked differences in the fauna suggest that the Bayan Mandahu Formation of Inner Mongolia is not coeval with the known Djadokhta localities in Mongolia. 相似文献
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Abstract: Patagoniaemys gasparinae gen. et sp. nov. is a new stem turtle found in central Patagonia, Chubut Province, Argentina, in outcrops of the La Colonia Formation (Campanian–Maastrichtian). This is a turtle of relatively large size (carapace length c. 70 cm), and the preserved remains of the holotype consist of skull fragments and several postcranial elements including a nearly complete vertebral column. A phylogenetic analysis shows Patagoniaemys gasparinae gen. et sp. nov. forming a monophyletic group with Otwayemys cunicularius and Mongolochelys efremovi, as a sister group to Meiolaniidae. A comprehensive review confirms that formed cervical vertebrae appeared independently several times during turtle evolution: in the clade that includes Patagoniaemys gasparinae gen. et sp. nov. and Meiolaniidae, in some baenids, in the total group Pleurodira and in crown group Cryptodira. Likewise, formed caudal vertebrae appeared several times in turtle evolution. 相似文献