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A new family, genus and species of damselfly, Burmaphlebia reifi gen. et sp. nov. (Burmaphlebiidae fam. nov.), is described as the second fossil odonate from Early Cretaceous Burmese amber. Its phylogenetic position is discussed and the fossil is attributed to a new family at the base of the anisozygopteran grade, probably closely related to the Recent relict group Epiophlebiidae. It is the first record of the ‘anisozygopteran’ grade from amber and the smallest known representative of this group.http://zoobank.org/6EFE7288-BD89-42F9-BFA5-804CE6B904A6  相似文献   

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Protomonimia kasai-nakajhongii gen. et sp. nov., is an angiosperm fructification with numerous helically arranged follicles attached to a concave receptacle. It was obtained from the mid-Cretaceous (Turonian) of Hokkaido, Japan. Each follicle is a conduplicate carpel with an adaxial stigmatic crest. It shows many primitive features of early angiosperms, especially of the Magnoliales.Protomonimia is thought to represent a member of a mid-Cretaceous group of magnolioid ancestors from which a major part of Recent Magnoliales may have been derived. Contributions from the Laboratory of Phylogenetic Botany, Chiba University, no. 118.  相似文献   

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Recent discoveries of fossil reproductive structures from deposits of the Raritan Formation in New Jersey (Turonian, Upper Cretaceous, ~90 million years BP) include a previously undescribed representative of the Order Capparales. The fossils are usually charcoalified with three-dimensional structure and excellent anatomical details. In the present contribution, we introduce a taxon represented by fossil flowers that have a combination of characters now found in the families of the Order Capparales sensu Cronquist. The fossil species is characterized by an unique suite of characters, such as the presence of a gynophore, arrangement of the sepals, unequal petal size, monothecal anthers, and a bicarpellate gynoecium, that are found in extant families of the Order Capparales. This new taxon constitutes an important addition to our understanding of Cretaceous angiosperm diversity and represents the oldest known fossil record for the Capparales. Heretofore, the oldest known capparalean was from the Late Tertiary sediments of North America.  相似文献   

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A new genus and species of Cretaceous Cyatheacean tree fern, Heilongjiangcaulis keshanensis gen. et sp. nov., is erected for several permineralized stems collected at the Keshan County in Songliao Basin, Heilongjiang Province, Northeast China. The new taxon is characterized by a dictyostelic, erect stem with dense multicellular scales and surrounded by persistent petiole bases and adventitious roots. The stem contains a central pith lacking medullary bundles, which is surrounded by a dictyostele, and the cortex externally. Each meristele of the dictyostelic ring is enclosed by a sclerenchyma sheath. The pith and cortex are parenchymatous. The proximal petiole bases present a frond trace composed of numerous meristeles, arranged in 1 abaxial and 2 adaxial arcs, with internally projecting bundles on the upper and lateral sides. The feature combination of the new genus is nearly identical to the anatomical structures of modern scaly genera of the Cyatheaceae apart from the absence of medullary bundles. It is interpreted as a primitive representative of early Cyatheaceae, that closely resembles the modern scaly genera, which suggests that in the Cretaceous, the tree ferns in this family were already in possession of most of the anatomical characteristics observed in extant taxa. The fossil records of the stems, petioles, and spores indicate that during the Jurassic and Cretaceous, the Northeastern region of Asia may have been one of the distribution centers of early Cyatheaceae.  相似文献   

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Abstract: The Spanish town of Galve (Teruel) is notable because of the abundance of Upper Jurassic and, especially, Lower Cretaceous vertebrates recorded there. Although most groups have been studied in detail, information on turtles is very limited even though the material is relatively abundant. So far, no turtle taxa have been identified at the generic level. The only Lower Cretaceous articulated specimen from Galve is analysed here. It is identified as a representative of Cryptodira, Galvechelone lopezmartinezae gen. et sp. nov. Galvechelone lopezmartinezae is determined as a taxon belonging to the node that groups the turtles traditionally assigned to ‘Macrobaenidae’ and ‘Sinemydidae’, and other taxa such as the members of Panchelonioidea. This node, very abundant in the Lower Cretaceous of Asia, and with a broad subsequent distribution, has recently been recognized in the Lower Cretaceous of Europe. The diversity of basal members of Eucryptodira in the European Late Jurassic (represented by Thalassemydidae, Plesiochelyidae and Eurysternidae) was high. Owing to a relative scarcity of well‐preserved early Cretaceous turtles from Europe, the knowledge of this group of reptiles is limited. The study of the new turtle from Galve, together with the recently described Hoyasemys jimenezi, and the recently completed review of the enigmatic Chitracephalus dumonii demonstrate that members of the cryptodiran node grouping ‘Macrobaenidae’, ‘Sinemydidae’ and Panchelonioidea were also very diverse in this period.  相似文献   

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An Early Cretaceous angiosperm, Sinocarpus decussatus gen. et sp. nov., is described from the Yixian Formation in Liaoning, China, based on an infructescence fragment. It is probably ebracteate, consisting of one terminal fruit and two pairs of pedicellate lateral fruits arranged decussately. Carpels are probably borne on a small convex receptacle. There are no distinct remnants of a perianth although fragments observed at the base of immature fruits may represent perianth parts. No remnants of androecial parts have been observed, and it is unknown whether the flowers were unisexual or bisexual. The basally syncarpous ovary is superior and composed of 3 or 4 carpels. Each carpel contains about 10 anatropous ovules/seeds borne along the linear placentae. Seeds are flattened and embedded in a thick amorphous material. The character combination of Sinocarpus indicates a systematic position among the basal grade of eudicots or the basal core eudicots, and particularly shows similarities to extant Ranunculaceae, Buxaceae, and Myrothamnaceae, but based on the available data the fossil cannot unambiguously be placed in any modern family.  相似文献   

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A single, permineralized ascoma resembling a pseudothecium assignable to the Pleosporales is described from the Eocene Appian Way fossil locality on Vancouver Island, British Columbia. The ascoma is globose, ostiolate, and erumpent on a fragment of the bark from an unidentified seed plant. Basally arranged asci contain large, multicelled, obovate ascospores within a single cavity or locule enclosed by a two-layered pseudoparenchymatous tissue that ostensibly represents ascostroma. Given this interpretation of the specimen's morphological features, Margaretbarromyces dictyosporus gen. sp. nov. represents the first report of a corticolous pleosporalean ascoma in the fossil record.  相似文献   

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We describe the new agglutinated foraminiferal genus and species Rectogerochammina eugubina nov. gen., nov. sp. from the Upper Cretaceous Scaglia Rossa Formation of the Umbria-Marche Basin in Italy. The genus differs from Gerochammina (Neagu, 1990) in the presence of a terminal uniserial part.  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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A fossil flower with affinities to the modern families of the saxifragalean complex is described. Fossils were collected at Old Crossman Pit, Raritan Formation, New Jersey, USA. These sediments are dated on the basis of palynology as Turonian (Upper Cretaceous, ~90 million years before present). Fossils are charcoalified and preserved with exceptional three- dimensional detail. The characters observed in these flowers, when compared with those of extant flowers of several families of the saxifragalean complex, suggest a close relationship with extant members of the Saxifragaceae and Hydrangeaceae. Hypotheses on the origin of petals and staminodes and a possible mechanism of pollination are discussed. This new taxon provides additional characters in the floral morphology of the fossil saxifragoids and extends their geographical distribution in the Cretaceous to North America.  相似文献   

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A new species, Keteleerioxylon kamtschatkiense, is described from the Cretaceous of the northwestern Kamchatka Peninsula on the basis of wood anatomy. Fossil wood showing anatomical characters of the modern genus Keteleeria is described from the Cretaceous of the Russian Far East for the first time.  相似文献   

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The first stag beetle found in Cretaceous Myanmar amber,Electraesalopsis beuteli Bai,Zhang & Qiu gen.& sp.nov.,is described and illustrated on the basis of one well-preserved specimen.This specimen provides more detailed morphological characters compared with compression fossils,e.g.the highly setose antennae and the punctured elytra.However,the systematic position of the new genus is still questionable and we provisionally place it as Lucanidae incertae sedis.In addition,the discovery ofElectraesalopsis Bai,Zhang & Qiu gen.nov.also indicates that there is very high biodiversity in Burmese amber.The new discoveries in future studies on Burmese amber will provide more information and improve our knowledge of biogeography and early evolution of the Lucanidae.  相似文献   

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A new fossil flower, Kajanthus lusitanicus gen. et sp. nov, is described from the Early Cretaceous (late Aptian–early Albian) Chicalhão site near the village of Juncal, western Portugal, based on a single coalified specimen. The flower is small, actinomorphic, trimerous and bisexual, slightly compressed and with floral organs tightly adhering. The perianth is organised in more than two whorls. The inner two whorls consist of six bulky, apparently fleshy parts. The outer perianth whorls consist of narrow parts. There are six stamens, arranged in two whorls. The filaments are thick and anthers tetrasporangiate. The pollen sacs are protruding with extrorse dehiscence. Pollen observed in situ is tricolpate, tectate, finely punctate-perforate, compressed and more or less spherical in polar view with a diameter of about 15 µm. The gynoecium is superior and composed of three free carpels. Non-destructive virtual sectioning of the single flower using synchrotron radiation X-ray tomographic microscopy revealed the presence of several curved ovules in each carpel, arranged in two longitudinal rows on marginal placentae. The character suite of the Kajanthus flower is only found in extant Lardizabalaceae (Ranunculales), where it is particularly close to Sinofranchetia, a monotypic genus that is now endemic to China.  相似文献   

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A new genus and species of fossil angiosperm (Appomattoxia ancistrophora) is established based on well-preserved fruiting units and associated pollen from the Early Cretaceous (Early or Middle Albian) Puddledock locality in the Potomac Group sequence of Virginia, eastern North America. Fruiting units are small, unilocular, and with a single, pendulous, orthotropous seed. The fruit surface is characterized by densely spaced unicellular spines with hooklike tips, which probably functioned in biotic dispersal. Pollen grains adhering to the stigmatic area of many specimens are monocolpate and tectate with granular to columellate infratectal structure, and are similar to dispersed grains assigned to Tucanopollis and Transitoripollis. Comparison of fossil Appomattoxia ancistrophora with extant plants reveals an unusual combination of characters that includes similarities with some magnoliid taxa, particularly Piperales (Piperaceae, Saururaceae) and Laurales (Chloranthaceae), as well as the monotypic ranunculid family Circaeasteraceae. Appomattoxia ancistrophora differs from extant Piperales in having a pendulous rather than erect ovule, and differs from extant Circaeaster in details of the fruit wall, as well as the presence of monosulcate rather than tricolpate pollen.  相似文献   

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The microsoroid ferns make up a large group in the family Polypodiaceae, easily characterized by the combination of at least partly clathrate rhizome scales and anastomosing reticulate venation. The diversification of this clade is poorly known, both because of unresolved generic delimitations and the lack of fossil records. In this work, we describe the first microsoroid macrofossil: Palaeosorum ellipticum sp. nov. F. M. B. Jacques & Z. K. Zhou. The fossil specimen, represented by part and counterpart, was found in the middle Miocene sediment of the Dajie Formation in Ailsohan, central Yunnan, southwest China. Epiphytic ferns belonging to Drynariaare found in different locations in Yunnan during the Pliocene. The fossil described in this study deepens the occurrence of epiphytic ferns in Yunnan back to the middle Miocene. It demonstrates that forests with complex ecological relationships have existed in southwest China for more than 10 million years.  相似文献   

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A new horned dinosaur, Gobiceratops minutus gen. et sp. nov. (Bagaceratopidae, Neoceratopsia), from the Upper Cretaceous Baruungoyot Formation of the Khermin Tsav locality (southern Mongolia) is described based on a 3.5-cm-long skull. The nasal included in the orbital border suggests relationship between the new taxon and Bagaceratops rozdestvenskyi. It is proposed that, unlike other neoceratopsian families, the family Bagaceratopidae is of Paleoasiatic origin.  相似文献   

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