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1.
China covers a vast territory harbouring a large number of aquatic plants.Although there are many studies on the β-diversity of total,herbaceous or woody plants in China and elsewhere,few studies have focused on aquatic plants.Here,we analyse a comprehensive data set of 889 aquatic angiosperm species in China,and explore the geographic patterns and climatic correlates of total taxonomic and phylogeneticβ-diversity as well as their turnover and nestedness components.Our results show that geograph...  相似文献   

2.
Species diversity of angiosperms(flowering plants) varies greatly among regions.Geographic patterns of variation in species diversity are shaped by the interplay of ecological and evolutionary processes.Here,using a comprehensive data set for regional angiosperm floras across the world,we show geographic patterns of taxonomic(species) diversity,phylogenetic diversity,phylogenetic dispersion,and phylogenetic deviation(i.e.,phylogenetic diversity after accounting for taxonomic diversity) across th...  相似文献   

3.
A total of 3 genera and 26 species of the Chinese Oretinae are represented in this paper; among them 13 species are described as new to science. All the type specimens are deposited in the Institute of Zoology. An account of the geographic distribution is given in accompanying with a distribution map. From the distribution of 23 species,of Oreta, the richest areas are ap-  相似文献   

4.
In the present paper,the origin of the fa-mily Perlidae and the distribution characters of the tribe and the subfamily were summarized and analyzed.Based on the distribution of the genera in the world,the eight distribution types of the genera were divided.In addition,the distribution characters of the Perlidae in China were also probed preliminarily.So far two subfamilies,four tribe and twenty genera have been found in China.Ten of them,of which three genera are endemic to China,are the Oriental genera;one Palaearctic genus;three Oriental-Palaearctic genera;one Oriental-Nearctic genus;four Oriental-Palaearctic-Nearctic genera and one Oriental-Palaearctic-Nearctic-Afrotropical genus.Moreover,the main distribution character of Chinese Perlidae is that most of the species distribute Central China region,South China region and Southwest China region.The Central China region centralizes the distribution and the break of the perlid species,and made the dispersal for the others regions.  相似文献   

5.
Samara (winged fruit) can be dispersed easily by wind and may be a crucial factor for angiosperm spread and diversification. In a narrow sense, a samara is an indehiscent dry fruit with wing(s) developed from fruit pericarp, while in a broad sense samaras also include all winged fruits with wings developed from both pericarp and peri-anth or bracts. According to the wing shape and growth patterns of samaras, we divided samaras into six types, i.e. single-winged, lanceolate-winged, rib-winged, sepal-winged, bract-winged, and perigynous samaras. Perigynous samaras can be further classified into two forms, i.e. round-winged and butterfly-winged samaras. Accordingly, the aerodynamic behavior of samaras can be classified into five types, autogyro, rolling autogyro, undulator, helicopter, and tumbler. The rib-winged and round-winged samaras can be found in Laurales, a basal angiosperm, and may represent the primitive type of early samaras. In the derived clades, samaras evolved enlarged but unequal wings and decreased wing loading (the ratio of fruit weight to wing size), which is likely an adaptation to gentle wind and secondary dispersal through water or ground wind. The wings of some samaras (such as sepal-winged and bract-winged samaras) may have multiple functions including wind dispersal, physical defense for the seeds, and adjust seed germination strategy. The pantropical family Malpighiaceae is extraordinarily rich in samara types, which is likely related to its multiple inter-continent dispersal in history, which is known as “Malpighiaceae Route”. Therefore, Malpighiaceae can be used as a model system for the studies on samara adaptation and evolution. We identified the following issues that deserve further examination in future studies using both ecological and evo-devo methods: 1) the adaption of different types of samaras in dispersal processes, 2) the molecular and developmental mechanism of sepal- and bract-wings, and 3) the evolution of samara types and their effects on angiosperm diversification. © 2018 Editorial Office of Chinese Journal of Plant Ecology. All rights reserved.  相似文献   

6.
The present paper deals with the coreid bugs collected by the Zoologico-BotanicalExpedition from various parts of Yunnan in 1955--1957 and from Omei-shan of Sze-chuan in the summer of 1955. The collection contains 93 species and 2 varieties dis-tributed in 41 genera of 4 subfamilies. Of these 7 genera, 27 species and one colorvariety are described as new and 5 genera and 21 species are recorded for the first time  相似文献   

7.
We review the fossil history of seed plant genera that are now endemic to eastern Asia. Although the majority of eastern Asian endemic genera have no known fossil record at all, 54 genera, or about 9%, are reliably known from the fossil record. Most of these are woody (with two exceptions), and most are today either broadly East Asian, or more specifically confined to Sino-Japanese subcategory rather than being endemic to the Sino-Himalayan area. Of the "eastern Asian endemic" genera so far known from the fossil record, the majority formerly occurred in Europe and/or North America, indicating that eastern Asia served as a late Tertiary or Quaternary refugium for taxa. Hence, many of these genera may have originated in other parts of the Northern Hemisphere and expanded their ranges across continents and former sea barriers when tectonic and climatic conditions allowed, leading to their arrival in eastern Asia. Although clear evidence for paleoendemism is provided by the gymnosperms Amentotaxus, Cathaya, Cephalotaxus, Cunninghamia, Cryptomeria, Glyptostrobus, Ginkgo, Keteleeria, Metasequoia, Nothotsuga, Pseudolarix, Sciadopitys, and Taiwania, and the angiosperms Cercidiphyllum, Choerospondias, Corylopsis, Craigia, Cyclocarya, Davidia, Dipelta, Decaisnea, Diplopanax, Dipteronia, Emmenopterys, Eucommia, Euscaphis, Hemiptelea, Hovenia, Koelreuteria, Paulownia, Phellodendron, Platycarya, Pteroceltis, Rehderodendron, Sargentodoxa, Schizophragma, Sinomenium, Tapiscia, Tetracentron, Toricellia, Trapella, and Trochodendron, we cannot rule out the possibility that neoendemism plays an important role especially for herbaceous taxa in the present-day flora of Asia, particularly in the Sino-Himalayan region. In addition to reviewing paleobotanical occurrences from the literature, we document newly recognized fossil occurrences that expand the geographic and stratigraphic ranges previously known for Dipelta, Pteroceltis, and Toricellia.  相似文献   

8.
The ostracodes were collected from the Taiyuan Formation of Xingyang, Gongxian area ,Henan. They comprise 35 species in 24 genera, of which 13 species in 7 genera are reported for the first time from China and 8 species in 2 genera are identified as planktonic elements. The discovery of planktonic ostracodes from the Taiyuan Formation is important for the reconstruction of palaeogeography and sedimentary history in this area during the  相似文献   

9.
Abundant and diverse microflora were discovered in the black shales of the Changzhougou Formation of the Changcheng System in the Pangjiabu Region of Hebei, located in the western part of the Yanshan Mountains. The microflora assemblage consists of 3 groups, 20 genera, and 75 species, including 2 new genera, 7 new species and 3 affinities. Systematic comparison of the obtained microfossils with the shale-facies  相似文献   

10.
Beta diversity(β-diversity) is the scalar between local(α) and regional(γ) diversity.Understanding geographic patterns of β-diversity is central to ecology,biogeography,and conservation biology.A full understanding of the origin and maintenance of geographic patterns of β-diversity requires exploring both taxonomic and phylogenetic β-diversity,as well as their respective turnover and nestedness components,and exploring phylogenetic p-diversity at different evolutionary depths.In this study,we ex...  相似文献   

11.
Genera Lamiophlomis and Paraphlomis were originally separated from genus Phlomis s.1. on the basis of particular morphological characteristics. However, their relationship was highly contentious, as evidenced by the literature. In the present paper, the systematic positions of Lamiophlomis, Paraphlomis, and their related genera were assessed based on nuclear internal transcribed spacer (ITS) and chloroplast rpl16 and trnL-F sequence data using maximum parsimony (MP) and Bayesian methods. and outgroup were sampled. Analyses of both separate In total, 24 species representing six genera of the ingroup and combined sequence data were conducted to resolve the systematic relationships of these genera. The results reveal that Lamiophlomis is nested within Phlomis sect. Phlomoides and its generic status is not supported. With the inclusion ofLamiophlomis rotata in sect. Phlomoides, sections Phlomis and Phlomoides of Phlomis were resolved as monophyletic. Paraphlomis was supported as an independent genus. However, the resolution of its monophyly conflicted between MP and Bayesian analyses, suggesting the need for expended sampling and further evidence.  相似文献   

12.
The results make it clear that there are total 11 families, 29 genera and 43 species of spiders in the rice field of Dong Fang Hong Farm. Among them, there are 8 families, 19 genera and 28 species in the early rice field, and 10 families, 27 genera and 36 species in the late rice field. The spatial distribution pattern of mixed spider populations in rice fields was different during different development stages of rice plant. During the prophase, metaphase and anaphase of early rice plant development, the spatial distribution pattern of mixed spider populations was aggregative, random and aggregative respectively. During the prophase, metaphase and anaphase of late rice plant development, the spatial distribution pattern was uniform, aggregative and uniform respectively.  相似文献   

13.
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15.
Yunnan is a province rich in flora.There are about 13,000 species of 1,984genera among 240 families(230 families of Angiospermae according to Hutchin-son's system and 10 families of Gymnospermae)in Yunnan.The number offamily in Yunnan is about 79.73% of 301 families in China,the number of genera64.88% of 3,058 genera in China,and the number of species 52% of 25,000species in China.The four very big families such as Orchidaceae,Compositae,  相似文献   

16.
An investigation of gamasid mites on the body surface of small mammals was carried out in Yunnan Province of China from 1990 to 2004. The small mammal hosts were captured from 25 counties which represent five geographical subregions, namely Middle Subregion of Hengduan Mountains, Southern Subregion of Hengduan Mountains, Eastern Plateau Subregion of Yunnan, Western Plateau Subregion of Yunnan and Southern Moun- tainous Subregion of Yunnan. The captured 10 803 small mammal hosts belong to nine families, 29 genera and 52 species in four orders (Rodentia, Insectivora, Scandentia and Lagomorpha). A total of 68 571 gamasid mites were collected from the body surface of the captured small mammal hosts and all the gamasid mites were identified to 10 families, 33 genera and 112 species. This paper lists all the mite species, together with their taxonomic position (genera and families) and their corresponding hosts. Much more mite species were found in the Middle Subregion of Hengduan Mountains than in other geographical subregions. The total individuals of mites and small mammals in the Middle Subregion of Hengduan Mountains are also the most plentiful in the five geographical subregions. Three dominant mite species and three dominant small mammal hosts were determined as the dominant species in the investigated areas of Yunnan Province. The dominant hosts are Rattus flavipectus (which accounts for 34.85% of the total individuals), Apodemus chevrieri (13.43%) and Rattus norvegicus (10.40%) while the dominant gamasid mite species are Laelaps nuttalli (Hirst, 1915) (27.84%), Laelaps echidninus (Berlese, 1887) (18.38%) and Laelaps guizhouensis (Gu et Wang, 1981) (14.79%). The results showed the high species diversity of gamasid mites in Yunnan Province and the uneven distribution feature in different subregions.  相似文献   

17.
Y.T.Hou 《古生物学报》1955,(3):226-244
The materials which form the subject of the present paper was collected fromthe Upper Devonian Hsiehkingssu formation of Changyang district,W.Hupeh.The majority of the ostracods are more or less ironized,and are usually wellpreserved.The specimens illustrated and described in this paper comprise 15 species in11 genera,of them 4 genera and 11 species are new.The Hsiehkingsuu formation of Changyang district of Hupeh is estimatedabout 30 meters in thickness.The ostracods obtained from the thin-bedded and  相似文献   

18.
The achene wail anatomy and surface sculpturing of 14 species representing Lactuca L. and related genera were Investigated to evaluate inter-and Intrageneric relationships. The achene wall anatomy of the studied species can be divided Into two types: winged and ribbed. The winged type is present in Lactuca L., Pterocypsela Shlh, Clcerblta Wallr., Chaetoserls Shlh and Stenoseris Shlh, and is characterized by protruding wings and costae in transverse section. Winged type achene mesocarps are composed of parenchymatous cells and fiber ceils, and the distinct fibrous strands are confined to the costae or wings of the achenes. The ribbed type is present in Notoseris Shih and Paraprenanthes Chang ex Shih, and Is characterized by only having costae In transverse section. Fiber cells are continuous in the costae and intercostae, in surface sculpturing, the ornamentation and the shape of epidermal cells are different among these genera. The results Indicate that L. altalca and L. serrlola should be conspeclfic, and that L. dollchophylla is probably an Intermediate taxon between Lactuca and Chaetoserls. The results also support the separation of Pterocypseia, Paraprenanthes, Notoseris, Chaetoseris and Stenoserls from Lactuca and Clcerblta as independent entitles. Close affinities between Pterocypsela and Lactuca, Paraprenanthes and Notoserls, and Chaetoserls and Stenoserls are also proposed.  相似文献   

19.
The elementary traits and diversity of embryonic setal patterns of 31 species of 22 genera, in three tribes of Hormaphidinae are studied. The embryonic setal patterns to every species are provided. Based on the parsimony principle and the developmental principle, these patterns are analyzed in each tribe following the terminology of Richards (1965). It is suggested that the setal patterns of abdominal tergites are the most important characters in embryonic and adult setal patterns. In conclusion, neoteny is a phylogenetic trend in the Hormaphidinae. Nipponaphidini and Hormaphidini have more typical neoteny in each genus and more diversity in different types of adult viviparous females than Cerataphidini, by showing more frequent and various protopatterns or mesopatterns.  相似文献   

20.
Cyprinidae, the largest fish family, comprises ap-proximately 210 recognized genera and 2010 species that are distributed widely in Eurasia, East Indian Is-land, Africa, and North America[1]. Species richness of this family is the greatest in East Asia, for example, China has 122 genera and more than 600 species. It is difficult to build a comprehensive phylogeny of Cy-prinidae due to the large number of genera and species. The classification of this family has been subject to revisions an…  相似文献   

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