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1.
The fossil leaf flora from the Shanwang Formation, Linqu County, Shandong Province, eastern China, is diverse, abundant, well preserved and discretely spaced, all of which make it suitable for the recognition and application of leaf physiognomic characters. This article is the first study of Chinese Tertiary floras using the CLAMP (Climate Leaf Analysis Multivariate Program) approach. Numerous bedding planes yield leaf assemblages through over 20 m thickness of diatomaceous shales within the Middle Miocene Shanwang Formation. The diatomaceous shales, containing abundant fossils, have been divided into 19 units. A working platform (3×3 m) in the Diatomite Quarry of Shanwang was studied for about 3 months in 1998 and as many fossils as possible were recorded layer by layer. This collecting method, used for the first time in the history of Shanwang research, enabled us to record the presence or absence of megafossils in distinct units so that we could investigate leaf physiognomic characteristics and palaeoclimate for each time interval. Leaf fossils from six units (5, 6, 7, 13, 15 and 16) have been used to estimate palaeoclimate parameters of the Shanwang area using the CLAMP 3B dataset. The predicted climate is that of a lakeside setting, at over 1000 m above sea level and within the 17–15-Ma time interval. Meteorological factors have been estimated using the CLAMP approach, including mean annual temperature (MAT; 9.5–11.2°C), warmest month mean temperature (20.2–22.5°C), growing season length (5.9–6.8 months), mean growing season precipitation (83–165 cm) and relative humidity (73–79%). MAT estimates from leaf margin analysis (LMA) range from 12.5 to 15.2°C, which are a maximum of 4° higher than those from our CLAMP analyses and from previous results of LMA studies of the Shanwang flora (10–13°C). Nearest living relatives (NLR) of other biota (pollen, fish, insects, diatoms, microthyriaceous fungi, etc.) indicate warm and moist temperate to subtropical conditions in the Shanwang area during the Miocene. CLAMP predictions are similar to the climate predicted from NLRs although the MAT prediction is a few degrees cooler. The fact that the Shanwang leaf flora is from a lacustrine sequence may have biased the CLAMP analysis towards cooler (and possibly wetter) climates. The modern Yangtze River valley is a reasonable environmental analogue for the Shanwang Middle Miocene, though Shanwang may have had cooler summers, cooler MAT and less seasonality in rainfall. The climate was essentially constant during deposition of the sequence studied, with possible minor variations in precipitation.  相似文献   

2.
In this paper two adjacent (Bo and Potamos) sections from the Early Tortonian of the island of Gavdos, Eastern Mediterranean, are extensively studied and compared as for their lithology and micropaleontological content with final aim their paleoecological and paleoenvironmental interpretation. These two sections are composed of clayey sediments and reefal limestones and of marls and sands of turbiditic origin, respectively. The qualitative and quantitative micropaleontological analyses that were realised in the contained benthic microfauna showed that the two sections are characterized by a shallowing upwards-general trend. However, the combined lithological and micropaleontological data suggest that, although adjacent, the two sections underwent different paleoenvironmental evolutions during the early Late Miocene: on the one hand, reef growth at the Bo shelf is suggestive of a current, providing warm, clear and low-nutrient waters to the shelf, and on the other hand, benthic foraminiferal assemblages from the Potamos shelf indicate cooler and eutrophic conditions, induced by enhanced river runoff and upwelling, impeding reefal promotion. This difference may be due to the separation of Bo and Potamos shelf by an island acting as a local oceanographic and biogeographic barrier.  相似文献   

3.
A new conodont species, Antognathus vjatsheslavi sp. nov., is described from the Famennian shallow-water carbonate deposits of the Bolshoi (Greater) Karatau Range in southern Kazakhstan.  相似文献   

4.
Eric Delson 《Geobios》1979,12(5):725-733
Prohylobates simonsi n. sp. is described on the basis of a partial mandible with M2–3 from the region of GebelZelten. It is nearly twice the size of the penecontemporaneous P. tandyi and has a relatively longer M3, but otherwise is nearly identical in morphology. Prohylobates is the most conservative known cercopithecid, presenting incomplete bilophodonty, possible cingulum remnants, high relative width of M2 and robust mandibular corpus. The variation in M3 length is comparable to that within some later cercopithecid species and between the species of Propliopithecus, the Oligocene catarrhine suggested to be nearest the ancestry of the Cercopithecidae. Parapithecus (including Simonsius) is not a cercopithecid ancestor  相似文献   

5.
Five new genera, Turononemonyxn. gen. (type species: Turononemonyxsamsonovin. sp.) (Nemonychidae: ? Cretonemonychinae: ? Cretonemonychini), Falsotanaosn. gen. (type species: Falsotanaos convexusn. sp.), Pretanaosn. gen. (type species: Pretanaosocularisn. sp.), Longotanaosn. gen. (type species: Longotanaosrasnitsynin. sp.) from Brentidae: Apioninae: Tanaini) and Turonerirhinusn. gen. (type species: Turonerirhinuskaratavensisn. sp.) from Curculionidae (Erirhininae: Erirhinini), and seven new species, Falsotanaosconvexusn. sp., Paratanaos samsonovin. sp., Pretanaos ocularisn. sp., Longotanaos rasnitsynin. sp., Turonerirhinus karatavensisn. sp., Turonerirhinuspunctatusn. sp. and Turonerirhinus poinarin. sp., are described from Kzyl-Dzhar locality (Kazakhstan, Upper Cretaceous, Turonian).http://www.zoobank.org/urn:lsid:zoobank.org:pub:13E0316E-C229-471A-90AA-2D71253B12F9  相似文献   

6.
The Madjars are a previously unstudied population from Kazakhstan who practice a form of local exogamy in which wives are brought in from neighboring tribes, but husbands are not, so the paternal lineages remain genetically isolated within the population. Their name bears a striking resemblance to the Magyars who have inhabited Hungary for over a millennium, but whose previous history is poorly understood. We have now carried out a genetic analysis of the population structure and relationships of the Madjars, and in particular have sought to test whether or not they show a genetic link with the Magyars. We concentrated on paternal lineages because of their isolation within the Madjars and sampled males representing all extant male lineages unrelated for more than eight generations (n = 45) in the Torgay area of Kazakhstan. The Madjars show evidence of extensive genetic drift, with 24/45 carrying the same 12‐STR haplotype within haplogroup G. Genetic distances based on haplogroup frequencies were used to compare the Madjars with 37 other populations and showed that they were closest to the Hungarian population rather than their geographical neighbors. Although this finding could result from chance, it is striking and suggests that there could have been genetic contact between the ancestors of the Madjars and Magyars, and thus that modern Hungarians may trace their ancestry to Central Asia, instead of the Eastern Uralic region as previously thought. Am J Phys Anthropol 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

7.
Abstract

The author reports the results of the herborizations carried out on the island Piana (northeastern Sardinia) located between Cape Ceraso and Cape Coda Cavallo. The flora consists of 250 entities distributed in 154 genera, inclusive of 54 families. The author gives information regarding the mail features of the vegetal coverage, and points out the presence of two species: Limonistrum monopetalum (L.) Boiss. and Omithoga-lum arabicum L., which are extremely rare in the little islands.  相似文献   

8.
Early Miocene fossils from Rusinga Island, Kenya, provide some of the best evidence for catarrhine evolution and diversification, and, together with more than eighty-five other mammalian species, form an important comparative reference for understanding faunal succession in East Africa. While there is consensus over the stratigraphic position of most of Rusinga's volcaniclastic deposits, the lacustrine Kulu Formation has been placed in various parts of the geological sequence by different researchers. To resolve this discrepancy, we conducted detailed geological analyses which indicate that the Kulu Formation was formed in the Early Miocene during a period of volcanic inactivity and subsidence following the early, mainly explosive hyper-alkaline phase of the Kisingiri complex and prior to the final eruptions of nephelinitic lavas. The underlying Hiwegi and older formations were locally deformed and deeply eroded before sedimentation began in the Kulu basin, so that the Kulu sediments may be significantly younger than the 17.8 Ma Hiwegi Formation and not much older than the overlying Kiangata Agglomerata-Lunene Lava series, loosely dated to ca. 15 Ma. The overall similarities between Kulu and Hiwegi faunas imply long-term ecological stability in this region. Our stratigraphic interpretation suggests that the Kulu fauna is contemporaneous with faunas from West Turkana, implying that differences between these assemblages—particularly in the primate communities—reflect paleobiogeographic and/or paleocological differences. Finally, the position of the Kulu Formation restricts the time frame during which the substantial faunal turnover seen in the differences between the primate and mammalian communities of Rusinga and Maboko Islands could have occurred.  相似文献   

9.
Among the 14 small mammal species from the early Miocene locality of the northern area of the Junggar basin (northern Xinjiang, China), four species are cricetids (Rodentia): unnamed species of Cricetodon and Eumyarion, and two new species, Karydomys debruijni nov. sp. and Megacricetodon beijiangensis nov. sp. Some aspects of the morphology of Cricetodon sp. are shared by Eucricetodon from the late Oligocene, suggesting that these specimens could be of intermediate form between Eucricetodon and Cricetodon. One tooth of Eumyarion sp. was found, making its determination uncertain, but its morphology is clearly differentiated from the one of Cricetodon sp. The species K. debruijni nov. sp. is established based on its primitive features compared to the species known in Europe and Anatolia, and its specific association of characters compared to Karydomys dzerzhinskii. M. beijiangensis nov. sp. shows many plesiomorphic features compared to the species already described in the middle Miocene of China. Based on both the whole assemblage of rodents and the species of cricetids, the biochronologic position and the age of the locality are discussed. The locality appears to be biochronologically very close to the fauna from the Chul’adyr Formation in Aktau Mountains, but we propose an age slightly older than the one proposed for this fauna, probably equivalent to the MN3 biozone in Europe.  相似文献   

10.
Abstract

Three species within the genus Calophyllum collected from middle Miocene Fotan Group sediments in Zhangpu County, Fujian, southeastern China are described in this paper. These fossils include Calophyllum zhangpuensis sp. nov., Calophyllum striatum, and Calophyllum suraikholaensis. The new fossil species C. zhangpuensis sp. nov. is oval, possesses entire leaves with closely spaced parallel secondary veins and has a round, or slightly retuse, apex. These specimens represent the first known fossil records of this relative wide leaf-type form of Calophyllum from China and have a length:width (L:W) ratio less than 3:1. In combination with the known modern geographic distribution and habitats of this wide leaf-type Calophyllum and other plants, data suggest that the middle Miocene Fotan flora is indicative of a warm climate. Thus, based on available fossil data, we speculate that this genus probably originated in India during the Paleocene before spreading from India to Bangladesh and into China, Sumatra, Malaysia, Indonesia, and Java during the Neogene, leading to its modern distribution. At least, the 3 fossil species in this region can explain floristic exchange between India, Fujian, and South China, which is consistent with previous studies; the occurrence of these 3 species indicates that Calophyllum began to diversity in China no later than the Miocene.  相似文献   

11.
Neeru Prakash   《Palaeoworld》2008,17(3-4):253
The Jabalpur Formation of Jabalpur series, named after Jabalpur city in Central India, is exposed along the Narbada River, in Satpura Basin. The series is divided into the lower Chaugan and the upper Jabalpur stages. The Jabalpur beds occur between Mahadevas and Lametas at Mahadeva Hills, exhibit highest Gondwanan strata, and embody diversified flora. These beds also extend laterally to Bairam and Belkher areas in western part of central India. The highest diversity of the floral assemblage is recorded in the central portion of the basin (Sehora and Hasnapur) whereas the lowest diversity is recorded in Morand River, Parsapani and Tilaksindoor areas. The diversity in floral assemblage indicates the dominance of conifers and pteridophytes along with cycadophytes and certain pteridosperms. The palynofloral assemblage from this formation contains pollen and spores of bryophytic, pteridophytic and gymnospermic groups. The palaeovegetational diversity, biostratigraphic correlation and phytogeographic distribution of the Jabalpur flora are discussed in comparison with various coeval floras of Indian peninsula along with contemporaneous deposits of the other Gondwanan regions. The palaeogeographic analysis suggests that the flora was thriving as mixed vegetation during Early Cretaceous under seasonally hot and dry or alternating with wet and dry condition.  相似文献   

12.
To date, there is no report on the genetic diversity of ticks in these regions. A total of 370 representative ticks from the south and east regions of Kazakhstan (SERK) and Xinjiang Uygur Autonomous Region (XUAR) were selected for molecular comparison. A fragment of the mitochondrial cytochrome c oxidase subunit I (cox1) gene, ranging from 631 bp to 889 bp, was used to analyze genetic diversity among these ticks. Phylogenetic analyses indicated 7 tick species including Hyalomma asiaticum, Hyalomma detritum, Hyalomma anatolicum, Dermacentor marginatus, Rhipicephalus sanguineus, Rhipicephalus turanicus and Haemaphysalis erinacei from the SERK clustered together with conspecific ticks from the XUAR. The network diagram of haplotypes showed that i) Hy. asiaticum from Almaty and Kyzylorda Oblasts together with that from Yuli County of XUAR constituted haplogroup H-2, and the lineage from Chimkent City of South Kazakhstan was newly evolved; and ii) the R. turanicus ticks sampled in Israel, Almaty, South Kazakhstan, Usu City, Ulugqat and Baicheng Counties of XUAR were derivated from an old lineage in Alataw City of XUAR. These findings indicate that: i) Hy. asiaticum, R. turanicus and Ha. erinacei shared genetic similarities between the SERK and XUAR; and ii) Hy. marginatum and D. reticulatus show differences in their evolution.  相似文献   

13.
中国蓼族(蓼科)植物区系的研究   总被引:1,自引:2,他引:1  
王珂  侯元同  高召兰  张璞  王小芬  李法曾   《广西植物》2007,27(2):197-202
根据蓼族植物的生境及分布状况,在全国范围内进行多年的野外考察和标本采集,同时参考前人的研究成果对中国蓼族植物区系进行深入研究。结果表明,中国蓼族植物有12属、170余种及变种,包括发现的多个新种(其中3新种已正式发表,1新种已被植物分类学报接受);同时揭示了其区系特点:(1)分布广泛,在全国各省区从低海拔到高海拔的区域内均有分布;(2)区系具温带性质,以北温带成分为主;(3)全国范围内,四川拥有该族在中国分布的全部12属,种及变种数占全国的51.7%,特有种数占全国的44.4%;云南分布11属占全国的91·7%,种及变种数占全国的62.2%,特有种数占全国的55.6%。这表明西南地区的云南、四川是中国蓼族植物的现代分布中心和多样化中心;(4)中国有该族植物12属,170余种及变种,分别占世界属种数的85.7%和48.0%~58.2%。可见中国(尤其是四川、云南)是世界蓼族植物的现代分布中心和多样化中心。  相似文献   

14.
Fossil fruits of Palaeocarya (Juglandaceae) are described from late Miocene sediments of southeastern Yunnan, China. The fruits present a tri-lobed wing consisting of an intact oblong-ovate middle lobe and two lateral lobes. The lobes are apically obovate, and have pinnate venation. The middle lobe is thicker at the base and gradually tapers to the apex. The nutlet, located at the base of the winged fruit, is round and hispid, and is subdivided by a septum into two compartments. Based on extensive morphological comparisons to previously documented fossil fruits, we found that the fossil fruits align most closely with members of the genusPalaeocarya, but have a unique combination of characters. Thus, we describe the fossils as a new species, Palaeocarya hispida sp. nov. This species represents an important range expansion for low-latitude occurrences of Palaeocarya in the late Miocene and therefore substantially improves our understanding of the biogeographic history of the genus. We propose that the wide distribution of Palaeocarya and relatively narrow distributions of close relatives, Engelhardia, Alfaropsis, and Oreomunnea, might be associated with a stepwise cooling and a major ice sheet expansion in the Antarctic and Arctic from the late middle Miocene to early Pliocene. In particular, the climatic oscillations during the Quaternary, such as the last glacial maximum, might have led to a decrease in the geographic distribution of Engelhardieae.  相似文献   

15.
The Miocene Santacrucian sloths are a very important assemblage because they represent the first major radiation among sloths and, therefore, they could provide many insights about sloth evolution and diversity. Based on other studies, the hearing capabilities of Pleistocene sloths were identified. For a deeper understanding of these capabilities from an evolutionary point of view, in this article we study the hearing capabilities of Santacrucian sloths. We estimate the frequency range and the best frequency of hearing of six species of stem-megatherines and one species of mylodont. In most cases, the best frequency of hearing is much lower than the expected value for the estimated body mass of the species. This general shift towards low values of frequency is different than the pattern observed in mammals where sound localisation is improved by an increased sensitivity to high frequencies. In this article, we also propose some palaeobiological inferences of the low-frequency shift of hearing range in Miocene Santacrucian sloths.  相似文献   

16.
A new jewel beetle genus, with one species (Cretofrontolina kzyldzharica gen. et sp. nov.) from the Upper Cretaceous of Kazakhstan is described based on a body; and three new species of the formal genus Metabuprestium are described based on isolated elytra: Metabuprestium sibiricum sp. nov. and M. arkagalense sp. nov. come from the Arkagala locality (Upper Cretaceous of Russia) and M. ichbogdense sp. nov. is from the Shar Tologoi locality (Lower Cretaceous of Mongolia).  相似文献   

17.
Here we report, for the first time, a very rich and diversified sponge assemblage from late Early Miocene deposits of a central part of the Vienna Basin (Paratethys) in Slovakia. Bodily preserved sponges are described as a new genus and species Paracinachyrella fossilis (Tetiliidae, Demospongiae). Dissociated spicules reveal the presence of the “soft” demosponges that belong to families Tetillidae, Theneidae, Geodiidae, Samidae, Thrombidae, Thoosidae, Agelasidae, Myxillidae, Bubaridae, and Tedaniidae, the lithistid family Pleromidae, and an undetermined rhizoclone-bearing lithistid. Fragments of dictyonal skeleton indicate the presence of hexactinellid sponges that belong to the families Farreidae and Euretidae, and lychniscosan sponges. We estimate that at least 16–19 different species of siliceous sponges inhabited this region of the Central Paratethys during the latest Burdigalian. Most of these sponges are reported for the first time from the Miocene of the Paratethys. This sponge fauna has clear Tethyan affinities and indicates the existence of connection between Paratethys and Tethys during the latest Burdigalian, as well as the presence of open marine, deep-water, bathyal conditions in this part of the Vienna Basin.  相似文献   

18.
The Miocene carbonate deposits of Scontrone (Abruzzo, Central Italy) are well known among palaeontologists because of their fossil vertebrate content that exhibits striking similarities to those of the remarkable “Terre Rosse” faunal complex of the Gargano region, defining the existence of the Miocene Central Mediterranean Apulia paleobioprovince. The main goal of this paper is to establish the age and environment of the Scontrone vertebrate bonebeds. The vertebrate remains are embedded in the basal portion of the Lithothamnion Limestone, a widespread carbonate-ramp lithosome representative of the Tortonian-early Messinian transgression over the entire Apulia Platform. The bonebeds belong to marginal-marine deposits (here called “Scontrone calcarenites”) preserved in a small area below transgressive ravinement surfaces. The rapid vertical and lateral facies variations displayed by the “Scontrone calcarenites”, together with paleoenvironmental considerations deriving from the vertebrate association, document a complex wave-dominated river-mouth depositional setting developed over a large, flat and semi-arid carbonate ramp. The “Scontrone calcarenites” have been split herein into five facies associations representing the stratigraphic response to a discontinuous or punctuated transgression within an overall rise of the relative sea level. Because of the absence of age-diagnostic fossils, the age of the “Scontrone calcarenites” cannot be directly defined through their paleontological content. However, a regional stratigraphic correlation between the Lithothamnion Limestone of Scontrone and the Lithothamnion Limestone of northern Majella, which is biostratigraphically well constrained, allows the attribution of the “Scontrone calcarenites” to the Tortonian.  相似文献   

19.
根据紫金山的自然条件和植被特点 ,对该区蕨类植物的区系和分布特点作重点分析 ,结果表明 :1)本区有蕨类植物 95种 (含亚、变种隶属 34科、6 0属 ,其中水龙骨科、鳞毛蕨科等 6科的种类占优 ;2 )本区蕨类植物中热带、亚热带属占总属数 88 33% ,具有典型的热带、亚热带性质 ;3)古老植物成分丰富 ,单种分布的种类较多 ;4 )本区系成分与海南最为密切 ,与江西、浙江密切 ,与河北、东北较为疏远 ;5)分布特点表现为具有 5种生态类型 ,种类集中在海拔 340~ 6 50m区域 .  相似文献   

20.
《Palaeoworld》2014,23(3-4):357-369
The analysis of fossil palynomorh assemblages in the Late Miocene freshwater sediments of the Sofia Basin (West Bulgaria) was done to collect data on the vegetation and climate dynamics during the Late Miocene. On the basis of pollen data, we described the main palaeocomunities developed in the region. The mixed mesophytic forests dominated the vegetation in which species of Quercus, Ulmus, Zelkova, Fagus, Carpinus, Betula, Castanea, Corylus, Pterocarya, Carya, Juglans, and Eucommia played important roles. Swamp forests were also recorded, including Taxodiaceae, Alnus, Glyptostrobus, Nyssa, and Myrica. Herbaceous vegetation was distributed in the middle part of the section, with a maximum of 35.5%. The vegetation dynamic passes through several phases, which were associated with changes in paleoclimate and palaeoecological conditions. Coexistence Approach (CA) was applied to palynological data to calculate four climatic parameters. The values of coexistence intervals for mean annual temperatures are 13.6–16.6 °C, with winter temperatures being 3.7–6.6 °C and summer temperatures being 23.6–27.8 °C. Mean annual precipitation ranged most frequently between 828 and 1308 mm. The palaeoclimatic reconstruction illustrates existence of a warm-temperate and relatively humid climate with higher mean annual temperature than the present day climate.  相似文献   

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