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Deming Wang Le Liu Meicen Meng Jinzhuang Xue Tuo Liu Yun Guo 《Die Naturwissenschaften》2014,101(8):615-622
Seed plants with ovules were abundant in the Late Devonian of Euramerica and they contribute significantly to our understanding of their early history. However, coeval ovules have been scarce in other regions of the world. Specimens of the seed plant Cosmosperma polyloba gen. et sp. nov. Wang et al. were recently obtained from the Upper Devonian (Famennian) Wutong Formation, at Fanwan Village, Changxing County, Zhejiang Province, China. This new seed plant has cupulate ovules, the uniovulate cupules with up to 16 distal segments and with minute spines on the outer surface, synangiate pollen organs bearing six to eight microsporangia fused only at the base, and planate and highly dissected pinnules in alternate arrangement. It differs from other Devonian seed plants mainly in the organization and position of the uniovulate and ornamented cupule, and in the highly dissected pinnules. Cosmosperma Wang et al. represents the first Devonian ovules recovered from China or eastern Asia and further illustrates the diversity of early spermatophytes. As for the Late Devonian seed plants, it is suggested that the pollen organs are synangiate and simple in organization, and the branches and leaves are generally planate. 相似文献
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A new bolosaurid parareptile, Belebey chengi sp. nov., is described from Dashankou, Gansu Province, China, a Middle Permian locality which is known mostly for its therapsid
fauna. The material consists of well-preserved mandibular and anterior skull remains and currently represents the largest
and latest surviving member of Bolosauridae. Phylogenetic analysis of bolosaurid interrelationships, the first analysis of
any clade of Early Permian parareptiles, indicates that the new taxon groups consistently with the other (Russian) members
of the genus Belebey, and forms the sister clade to the genus Bolosaurus from North America. The Early Permian Eudibamus cursoris from Germany falls into the basal most position within Bolosauridae. Our analysis also shows that the split between the main
bolosaurid lineages must have occurred near or before the Permo-Carboniferous boundary and that the paleo-equatorial region
of Laurasia probably served as the center of origination for these parareptiles. A similar pattern can be found in other clades
of Paleozoic amniotes, suggesting that this may be the general trend in early amniote evolution. 相似文献
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The Luoping fauna (Anisian, Middle Triassic) is probably the oldest of Triassic faunas in Guizhou–Yunnan area, China. The reptilian assemblage is comprised of ichthyosaurs, a number of sauropterygians (pachypleurosaur-like forms), saurosphargids, protorosaurs, and archosauriforms. Here, we report on a peculiar reptile, newly found in this fauna. Its dentition is fence or comb-like and bears more than 175 pleurodont teeth in each ramus of the upper and lower jaws, tooth crown is needle-like distally and blade-shaped proximally; its rostrum strongly bends downward and the anterior end of its mandible expands both dorsally and ventrally to form a shovel-headed structure; and its ungual phalanges are hoof-shaped. The specializations of the jaws and dentition indicate that the reptile may have been adapted to a way of bottom-filter feeding in water. It is obvious that such delicate teeth are not strong enough to catch prey, but were probably used as a barrier to filter microorganisms or benthic invertebrates such as sea worms. These were collected by the specialized jaws, which may have functioned as a shovel or pushdozer (the mandible) and a grasper or scratcher (the rostrum). Our preliminary analysis suggests that the new reptile might be more closely related to the Sauropterygia than to other marine reptiles. 相似文献
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Apesteguía S 《Die Naturwissenschaften》2004,91(10):493-497
Ornithischian and theropod dinosaurs were morphologically diverse during the Cretaceous. In contrast, sauropods were relatively more conservative. The anatomy of Bonitasaura salgadoi, a new 9-m titanosaurian sauropod from Upper Cretaceous beds of Patagonia, suggests that sauropod anatomical diversity would have included unexpected items. Its unusual, rectangular lower jaw possesses narrow, anteriorly restricted teeth and shows evidence of a sharp keratinous sheath over the non-dentigerous region that probably worked to guillotine plant material. This discovery definitely demonstrates that titanosaurs acquired a mandibular configuration similar to that of some basal diplodocoids, as had already been suggested by the lower jaw of the controversial genus Antarctosaurus. This oral configuration, plus the beak-like structure and the skull shape, resemble some traits more commonly seen in Laurasian ornithischians, mostly unexpressed in southern continents. A high sauropod morphological diversity seems to be in agreement with the poorly represented ornithischian clades of the southern hemisphere.Communicated by G. Mayr 相似文献
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Tertiary marsupial records are very scarce in Asia. A new peradectine marsupial, Junggaroperadectes burqinensis gen. et sp. nov., is reported from the Early Oligocene Keziletuogayi Formation in the Burqin region, Xinjiang, China. This
new species is based on a single right upper M2. The tooth possesses a straight centrocrista, a characteristic of peradectines.
Its main cusps lean buccally, with the paracone being smaller and lower than the metacone. The conules and stylar cusps are
weakly developed. These characters distinguish J. burqinensis from Euro-American Tertiary peradectines, but they also imply a close phylogenetic relationship to Siamoperadectes and Sinoperadectes, two Asian Early Miocene peradectines. 相似文献
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The unusual presence of long pennaceous feathers on the feet of basal dromaeosaurid dinosaurs has recently been presented as strong evidence in support of the arboreal–gliding hypothesis for the origin of bird flight, but it could be a unique feature of dromaeosaurids and thus irrelevant to the theropod–bird transition. Here, we report a new eumaniraptoran theropod from China, with avian affinities, which also has long pennaceous feathers on its feet. This suggests that such morphology might represent a primitive adaptation close to the theropod–bird transition. The long metatarsus feathers are likely primitive for Eumaniraptora and might have played an important role in the origin of avian flight.Electronic Supplementary Material Supplementary material is available for this article at 相似文献
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目前,国内针对沙氏外硫红螺菌的研究鲜见报道。为了挖掘功能光合细菌新菌源,从茂名水东湾红树林潮间带泥样分离到1株能以硫化物作为电子供体营光合自养作用的紫色光合细菌HBL-1。根据菌株的形态、细胞色素光吸收特征及自动微生物鉴定系统检测的碳源利用结果,结合系统发育分析,鉴定该菌为沙氏外硫红螺菌(Ectothiorhodospira shaposhnikovii)。该菌培养条件粗放,尤其在偏碱性、含盐、光照微氧条件下生长最快;该菌能耐受较高浓度的Na_2S,在Na_2S初始浓度为227.6 mg/L时,培养6 d后,Na_2S转化率达到66.9%。结果表明该菌在水质净化方面显示较好的应用前景。 相似文献
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Ryoko Matsumoto Shigeru Suzuki Khisigjav Tsogtbaatar Susan E. Evans 《Die Naturwissenschaften》2009,96(2):233-242
New material of the enigmatic diapsid Khurendukhosaurus is described from the Mongolian type locality, Khuren Dukh, providing additional data on the vertebral column, pelvis, and
hind limb. It confirms the choristoderan status of the genus and permits a more detailed phylogenetic analysis that supports
a relationship between Khurendukhosaurus and the long-necked Asian Hyphalosauridae. The existence of tall caudal neural spines implies that Khurendukhosaurus was a deep-tailed swimmer. This and the open sacral costocentral sutures suggest a primarily aquatic lifestyle.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Institutional abbreviations MNHN BL, Museum National d’Histoire Naturelle, Paris, France; MPC, Mongolian Paleontological Center; PIN, Paleontologicheski
Institut, Akademii Nauk, Moscow; HMNS, Hayashibara Museum of Natural Sciences, Okayama, Japan. 相似文献
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Ulysse Lefèvre Andrea Cau Aude Cincotta Dongyu Hu Anusuya Chinsamy François Escuillié Pascal Godefroit 《Die Naturwissenschaften》2017,104(9-10):74
Genuine fossils with exquisitely preserved plumage from the Late Jurassic and Early Cretaceous of northeastern China have recently revealed that bird-like theropod dinosaurs had long pennaceous feathers along their hindlimbs and may have used their four wings to glide or fly. Thus, it has been postulated that early bird flight might initially have involved four wings (Xu et al. Nature 421:335–340, 2003; Hu et al. Nature 461:640–643, 2009; Han et al. Nat Commun 5:4382, 2014). Here, we describe Serikornis sungei gen. et sp. nov., a new feathered theropod from the Tiaojishan Fm (Late Jurassic) of Liaoning Province, China. Its skeletal morphology suggests a ground-dwelling ecology with no flying adaptations. Our phylogenetic analysis places Serikornis, together with other Late Jurassic paravians from China, as a basal paravians, outside the Eumaniraptora clade. The tail of Serikornis is covered proximally by filaments and distally by slender rectrices. Thin symmetrical remiges lacking barbules are attached along its forelimbs and elongate hindlimb feathers extend up to its toes, suggesting that hindlimb remiges evolved in ground-dwelling maniraptorans before being co-opted to an arboreal lifestyle or flight. 相似文献
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从理论到实践的美国排污交易 总被引:9,自引:2,他引:9
阐述了排污交易产生的背景,排污权与排放许可证的概念,TDP的理论研究和实践应用,排污交易政策在美国的发展等。美国的排污交易政策由补偿政策、气泡政策、净得政策和排污银行4项组成,以美国酸雨计划为例说明了排污交易的巨大环境经济效益,并给出了建议。 相似文献
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A skull from the Barstovian of South Dakota has typical leptarctine characteristics, including robust zygomatic arches, double sagittal crests, grooves on the lingual side of the lower canines, and bony projections from the tympanic bullae. The robust mandibles and expanded masseteric fossa of this specimen indicate that it had large jaw muscles. Dental morphology and other characters lead us to agree with earlier suggestions that Hypsoparia is a valid genus. The morphology of Hypsoparia suggests that leptarctines were more herbivorous than most other Carnivora. 相似文献
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de Bonis L Peigné S Likius A Mackaye HT Vignaud P Brunet M 《Die Naturwissenschaften》2007,94(7):575-580
We report on the oldest fox (Canidae) ever found in Africa. It is dated to 7 Ma based on the degree of evolution of the whole
fauna. It belongs to a new species. Its overall size and some morphological characteristics distinguish the Chadian specimen
from all the other foxes. The presence of Vulpes and of the genus Eucyon in slightly younger African locality, as well as in southwestern Europe in the late Miocene, may indicate that canids migrated
in Europe from Africa through a trans-Mediterranean route. 相似文献