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1.
A new species, Piceoxylon burejense sp. nov. (Pinaceae), is described from the Middle Maastrichtian (Upper Cretaceous) of the Zeya-Bureya Basin, Amur Region (Russian Far East) based on the fossil wood anatomy. The new species is characterized by a combination of anatomical wood features of the modern genera Picea and Larix. The fossil wood of Pinaceae was found in the Cretaceous deposits of the Amur Region for the first time.  相似文献   

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Linaria qartobensis, from southern Iberian Peninsula, is here newly described, illustrated and compared with its morphologically closest relatives from L. sect. Supinae: L. ricardoi and L. orbensis. The new species is characterized by longer calyx lobes, corolla and spur, violet corolla with yellow‐orangish palate, big and globose capsule, and seeds with black and prominently white‐tuberculate disc and subentire wing. Linaria qartobensis is an endemic species growing on marly deposits from the Guadalquivir river basin, in the Córdoba province (Andalusia, Spain).  相似文献   

4.
A new genus ( Protosciadopityoxylon gen nov. ) of Early Cretaceous fossil wood reported in the present paper was discovered from Liaoning Province, China, and is named as a new species:Protosciadopityoxylon liaoningense gen. et sp. nov. It is described here and this generic name, adopted by the authors, is employed for fossil wood that is believed to be nearly related to the recent genus Sciadopitys and the fossil genus Sciadopityoxylon. The new genus bears some similarities to Protophyllocladoxylon,Protocircoporoxylon and Xenoxylon in different geological ages, but it differs from them in the types of cross-field pitting.  相似文献   

5.
New species of the Pinaceae, Abies chavchavadzeae and Piceoxylon ussuriense, are described on the basis of fossil woods from the Pliocene of the Pavlovka lignite field (southern Primorye). For the first time, fossil wood of Abies is reported from the Russian Far East.  相似文献   

6.
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   

7.
Silicified coniferous wood was collected from the Lanqi Formation (late Middle Jurassic in age) at Shebudaigou Village, Liaoning Province, China. Three taxa are identified, namely Pinoxylon dacotense Knowlton, Xenoxylon phyllocladoides Gothan, and Araucariopitys sp. Based on these new data, and those of other fossil plants reported previously from the same formation, we consider the climate during the deposition of the Lanqi Formation was subtropical, humid and seasonal. In this respect the Lanqi flora differs from the coeval Shimengou and Longmen floras from North China. The Longmen flora was deposited during more humid, subtropical conditions, while the Shimengou Formation indicates that the climate was warm temperate and dry. Our data would suggest that the Late Jurassic climatic pattern was initiated as early as the late Middle Jurassic.  相似文献   

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Pinus mutoi is described as a new species on the basis of a permineralized seed cone from the Upper Cretaceous of Hokkaido, Japan. The cone is at least 20 cm long and up to 6 cm in diameter, consisting of a cone axis and numerous cone-scale complexes that are arranged helically around the axis. Two winged seeds are borne on the adaxial surface of each ovuliferous scale. Each complex receives a single trace from the vascular cylinder of the cone axis. In the scale base, all the resin canals occur abaxially to the vascular strand. The spatulate bract of the fossil is unique to the specimen among the cones of both living and fossil Pinus. The central umbo, broad sclerotic cortex of cone axis, and absence of serotinous features of the fossil cone suggest affinity with the subsection Sylvestres of the section Pinus, subgenus Pinus. This is the first record of permineralized preserved Pinus cone from the Cretaceous of Eastern Eurasia.  相似文献   

10.
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   

11.
Some problems in the taxonomy of the Juglandaceae are discussed based on wood anatomy; the identification of fossil juglandaceous wood is considered. Data on fossil wood of the Juglandaceae are summarized; a key for identification of wood anatomy in modern and fossil Juglandaceae is compiled. Wood anatomical characters in members of the family are discussed in the light of major evolutionary trends in the secondary xylem of dicots, and a comparative characterization of members of the family is developed. A hypothesis is proposed that the subfamily Engelhardioideae is the most primitive member of the Juglandaceae based on wood anatomy, the tribe Juglandeae and subfamily Platycaryoideae are slightly more highly specialized, and the tribe Hicorieae is the most advanced. Evolutionary relationships between the members of the Juglandaceae are reviewed based on wood anatomy.  相似文献   

12.
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   

13.
A new silicified wood, Sclerospiroxylon xinjiangensis Wan, Yang et Wang nov. sp., is described from the Cisuralian (lower Permian) Hongyanchi Formation in southeast Tarlong section, Turpan City, Xinjiang Uygur Autonomous Region, northwestern China. The fossil wood is composed of pith, primary xylem and Prototaxoxylon-type secondary xylem. The pith is solid, circular, heterocellular, with sclerenchyma and parenchyma. The primary xylem is endarch to mesarch, with scalariform thickenings on tracheid walls. The secondary xylem is pycnoxylic, composed of tracheids and parenchymatous rays. Growth rings are distinct. Tracheids have mostly uniseriate, partially biseriate araucarian pitting on their radial walls. Helical thickenings are always present on both the radial and the tangential walls. Rays are 2–14 cells high, with smooth walls. There are 2 to 7, commonly 2 to 4 cupressoid pits in each cross-field. Leaf traces suggest that Sxinjiangensis nov. sp. was evergreen with a leaf retention time of at least 15 years. Based on the sedimentological evidence, growth rings within the Sxinjiangensis nov. sp. could have been caused by seasonal climatic variations, with unfavorable seasons of drought or low temperature. Low percentage of latewood in each growth ring is probably due to the intensity of climatic seasonality and/or long leaf longevity.  相似文献   

14.
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   

15.
Abstract:  Previously known from the Kimmeridgian–Portlandian of Dorset (UK) only, Protocupressinoxylon purbeckensis wood is reported here from the Kimmeridgian of Asturias (Spain) and Ajoie (Switzerland). The morphospecies taxonomy and nomenclature are discussed, and new supplementary illustrations are given. The P. purbeckensis tree was growing in dry strongly seasonal (tropophilous) environments, and the new occurrences suggest that such a climate prevailed on land all over southwestern Europe at the end of the Jurassic (Kimmeridgian sensu anglico – Portlandian). The review of fossil wood data indicates that such a stressful environment may have constrained terrestrial biocoenoses and their evolution at the Jurassic/Cretaceous boundary. But wood generic diversity curves are also strikingly similar to that drawn 20 years ago for nonmarine tetrapods, implying a fossil Lagerstätte effect.  相似文献   

16.
The hot-spring waters of numerous hot springs at the Kamchatka Peninsula, Russia differ in their chemical characteristics and elemental composition. Total bacterial abundance (TBA) as well as enzymatically active and respiring bacteria was enumerated in water samples collected from the Nalychevskie, Oksinskie, Apapelskie, and Dachnye hot springs. 5-Carboxyfluorescein diacetate activity was detected in all water samples and comprised 29-65% of the TBA as determined by 4',6-diamidino-2-phenylindol staining. The respiratory activity of iron-oxidizing bacteria was assayed by 5-cyano-2,3-ditolyltetrazolium chloride reduction. Respiring cells accounted for 9-14% of the TBA, indicating a positive correlation with the number of iron-oxidizing bacteria from the hot-spring biomats. Enumeration of heterotrophic bacteria revealed a high-density bacterial population only in the water of the Apapelskie hot spring, which has a temperature of 36 degrees C. Therefore, it appears that heterotrophic and iron-oxidizing bacteria inhabiting the hot-spring waters are essential for the geochemical processes occurring in hydrothermal systems.  相似文献   

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18.
New fossil species of Piceoxylon (Pinaceae), P. talovskiense sp. nov. and P. kamtschatkiense sp. nov., are described on the basis of wood anatomy from the Cretaceous and Paleogene (respectively) of the Talovka River basin in the northwestern Kamchatka Peninsula. The Late Cretaceous P. talovskiense sp. nov. shows wood characters of modern Picea. The wood anatomy of the Paleogene Piceoxylon kamtschatkiense sp. nov. is somewhat similar to those of modern Picea sitchensis and P. jezoensis. Fossil woods of Piceoxylon have been found in the Kamchatka Peninsula for the first time.  相似文献   

19.
Comptoniaster adamsi nov. sp. (Asteroidea, Valvatida, Goniasteridae) is described from the middle Cretaceous (Cenomanian-Turonian) Britton Formation of northcentral Texas, USA. The new species provides the focus for an exploratory cladistic analysis of Mesozoic asteroids of the Comptoniaster-Tylasteria Group sensu G. Breton. The systematics of Mesozoic goniasterids has relied heavily on the morphology of marginal ossicles, which generally are the best-preserved elements of the skeleton. Unfortunately, marginal ossicular data are scanty for most species because ossicles tend to be morphologically simple yet varied even within individuals, and few even partially articulated specimens are available to provide more comprehensive information. Further, both plesiomorphy and homeomorphy have been important. Because of limited available data, phylogenetic reconstruction here is preliminary. Nevertheless, a number of taxon groupings recognized in the literature are recovered, and stratigraphic distribution provides some support for results. Data unfortunately are particularly incomplete for species of Comptoniaster, the focus of the study. Comptoniaster adamsi nov. sp. clustered with three other species assigned to the genus, including the type, all Cretaceous in age. Jurassic species of Comptoniaster are more widely distributed in the analysis, perhaps reflecting an early stage in diversification or perhaps suggesting the need for species assignment reassessment, but also reflecting the limited available data.  相似文献   

20.
Foliar cuticle of a new species of Ruflorinia, R. orlandoi Carrizo et Del Fueyo, from the Lower Cretaceous Springhill Formation in Santa Cruz province, Argentina, is herein described with light and electronic (scanning and transmission) microscopy. The fronds of R. orlandoi nov. sp. are bipinnate and imparipinnate with a conspicuous main rachis bearing alternate to sub-opposite pinnae. Cuticular striations and hairs are present in both epidermises whereas stomata are only on the abaxial cuticle. Stomata have several papillate subsidiary cells and the guard cells are sunken. Ultrastructurally the adaxial and abaxial cuticles are composed of three and two cuticular layers, respectively. The cuticular characters here described are interpreted as a response to a possible adaptation to a wet climate as well as to the fluctuating environment produced by the gradual transition from fluvial to an estuarine and marine setting that characterizes the Springhill Formation. The discovery of this new species allows expanding the previous knowledge of the paleofloristic composition of the Springhill Formation with the addition of the first pteridospermous megafossil described for this formation. Moreover, the record of Ruflorinia orlandoi nov. sp. in the Springhill Formation highlights the importance of the Caytoniales during the Cretaceous in Patagonia.  相似文献   

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