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1.
The Vernonieae is one of the major tribes of the largest family of flowering plants, the sunflower family (Compositae or Asteraceae), with ca. 25,000 species. While the family's basal members (the Barnadesioideae) are found in South America, the tribe Vernonieae originated in the area of southern Africa/Madagascar. Its sister tribe, the Liabeae, is New World, however. This is the only such New/Old World sister tribe pairing anywhere in the family. The Vernonieae is now found on islands and continents worldwide and includes more than 1500 taxa. The Vernonieae has been called the "evil tribe" because overlapping character states make taxonomic delimitations difficult at all levels from the species to the subtribe for the majority of taxa. Juxtaposed with these difficult-to-separate entities are monotypic genera with highly distinctive morphologies and no obvious affinities to any other members of the tribe. The taxonomic frustration generated by these contrary circumstances has resulted in a lack of any phylogeny for the tribe until now. A combined approach using DNA sequence data from two chloroplast regions, the ndhF gene and the noncoding spacer trnL-F, and from the nuclear rDNA ITS region for 90 taxa from throughout the world was used to reconstruct the evolutionary history of the tribe. The data were analyzed separately and in combination using maximum parsimony (MP), minimum evolution neighbor-joining (NJ), and Bayesian analysis, the latter producing the best resolved and most strongly supported tree. In general, the phylogeny shows Old World taxa to be basal and New World taxa to be derived, but this is not always the case. Old and New World species are found together in two separate and only distantly related clades. This is best explained by long-distance dispersal with a minimum of two trans-oceanic exchanges. Meso/Central America has had an important role in ancient dispersals between the Old and New World and more recent movements from South to North America in the New World.  相似文献   

2.
Temperate forests of southern South America are globally important because of their high level of endemism. I argue here that within southern South America, rainforests of the Chilean Coastal Range should be the primary target for new conservation efforts. Historically, most protected areas in southern South America have been designated to preserve forests above 600 m, mainly in the Andes. However, Coastal Range forests have higher species richness and are under greater threat than Andean forests at similar latitudes. Coastal forests are characterized by the presence of numerous narrow-range endemics, among them two monotypic plant families. The higher frequency of endemic species in Coastal Range forests is attributed to its more stable biogeographic history compared to the Andes, particularly during the glacial events of the Quaternary. Due to the extent of human impact, the remaining fragments of coastal forests are quite distant from one another, and are disconnected from the larger protected areas of Andean forests. Only 439000 ha of Valdivian coastal forest still remain, including some remnants of primary forest. New private or public reserves should be created to protect the last remnants of continuous forest remaining on the Coastal Range of the Valdivian region (40–42° S). A different conservation strategy should be applied north of 40° S, where protected areas are too small and fragments are too scattered to maintain viable populations of most vertebrates. In this latter area, I recommend expanding existing reserves, restoring native forests, and interconnecting remnant forests through a corridor network.  相似文献   

3.
Seven species and one sub-species of Mecoptera are aquatic as larvae and pupae. All aquatic species are classified in two genera of the family Nannochoristidae and have very restricted geographic ranges, with three species confined to extreme southern South America, three species and one sub-species confined to New South Wales or Tasmania in Australia, and one species confined to the South Island of New Zealand. Guest editors: E. V. Balian, C. Lévêque, H. Segers & K. Martens Freshwater Animal Diversity Assessment  相似文献   

4.
Molecular phylogenetic analyses of 26 of the 28 species of Ourisia , including eight of ten subspecies and two purported natural hybrids, are presented and used to examine the biogeography of the genus, which is distributed in subalpine to alpine habitats of South America, New Zealand and Tasmania. Gondwanan vicariance, often cited as the cause of this classic austral biogeographical pattern, was rejected by parametric bootstrapping of our combined dataset. Alternatively, various lines of evidence are presented in favour of a South American origin of Ourisia and subsequent dispersal to Australasia. Specifically, the genus likely arose in the Andes of central Chile and spread to southern Chile and Argentina, to the north-central Andes, and finally to Tasmania and New Zealand. The ancestor of the New Zealand species probably first arrived on the South Island, where the New Zealand species of Ourisia are most diverse, and migrated to the North and Stewart Islands. Because the Tasmanian and New Zealand species are sister to one another, the direction of dispersal between these two areas is equivocal. These results agree with other molecular phylogenetic studies that show that past dispersal between southern hemisphere continents has played an important role in the evolutionary history of many high-elevation austral plants. Our data also show that within South America, many of the geographical barriers (with the exception of the Atacama Desert) that have played a role in the evolution of other plant groups have not affected Ourisia species. Within New Zealand, the phylogeny and biogeography of species of Ourisia coincide with the geological history of the country and patterns of other alpine plants. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 87 , 479–513.  相似文献   

5.
Three new species of Notidobiella Schmid (Insecta: Trichoptera) are described from South America: Notidobiella amazonianasp. n. (Brazil), Notidobiella brasilianasp. n. (Brazil), and Notidobiella ecuadorensissp. n. (Ecuador). In addition, the 3 previously described species in the genus, Notidobiella chacayana Schmid, Notidobiella inermis Flint, and Notidobiella parallelipipeda Schmid, all endemic to southern Chile, are redescribed and illustrated, including the females of each species for the first time, and a key to males of the species in the genus is provided. The occurrence of Notidobiella in Brazil and Ecuador represents a significant extension of the range of the genus beyond southern Chile where it previously was thought to be endemic. The biogeography of Sericostomatidae and other austral South American Trichoptera is reviewed. The presence of the family in South America may not be part of a "transantarctic" exchange, but instead may represent an earlier occurence in the region. The distribution of Notidobiella in tropical South America likely represents recent dispersal from southern South America to the north.  相似文献   

6.
The distribution patterns of many fishes between the three continents (Africa, Australia, and South America) in the Southern Hemisphere have been uncovered to be influenced by mostly vicariance or historical dispersal. Although some demersal fishes with intercontinental distribution are suggested to be more influenced by current/recent dispersal, few genetic studies have been made for demersal fishes so far. To provide more information for such fishes, genetic divergence was analyzed for two pairs of gadiform species and subspecies distributed around Australasia and South America: the blue grenadier, Macruronus novaezelandiae (from New Zealand) and the Patagonian grenadier, M. magellanicus (from South America) as well as two subspecies of the southern blue whiting, Micromesistius australis pallidus (from New Zealand) and M. a. australis (from South America). The sequence analyses of two mitochondrial DNA regions showed no divergence between Australasian and South American populations of the grenadiers and the southern blue whiting. The microsatellite DNA analysis also indicated significant but very minimal genetic differentiation between the two geographic populations of each pair. These results imply rather recent separation of the two geographic populations. Current/recent dispersal may be an important common factor for determining the distribution of demersal fishes in the Southern Hemisphere. Nonetheless, low but significant genetic differentiation observed requires treating the two populations of the economically important grenadiers and southern blue whiting, respectively, as different stocks for proper resource management.  相似文献   

7.
Aim The aim of this paper is to analyse the biogeography of Nothofagus and its subgenera in the light of molecular phylogenies and revisions of fossil taxa. Location Cooler parts of the South Pacific: Australia, Tasmania, New Zealand, montane New Guinea and New Caledonia, and southern South America. Methods Panbiogeographical analysis is used. This involves comparative study of the geographic distributions of the Nothofagus taxa and other organisms in the region, and correlation of the main patterns with historical geology. Results The four subgenera of Nothofagus have their main massings of extant species in the same localities as the main massings of all (fossil plus extant) species. These main massings are vicariant, with subgen. Lophozonia most diverse in southern South America (north of Chiloé I.), subgen. Fuscospora in New Zealand, subgen. Nothofagus in southern South America (south of Valdivia), and subgen. Brassospora in New Guinea and New Caledonia. The main massings of subgen. Brassospora and of the clade subgen. Brassospora/subgen. Nothofagus (New Guinea–New Caledonia–southern South America) conform to standard biogeographical patterns. Main conclusions The vicariant main massings of the four subgenera are compatible with largely allopatric differentiation and no substantial dispersal since at least the Upper Cretaceous (Upper Campanian), by which time the fossil record shows that the four subgenera had evolved. The New Guinea–New Caledonia distribution of subgenus Brassospora is equivalent to its total main massing through geological time and is explained by different respective relationships of different component terranes of the two countries. Global vicariance at family level suggests that Nothofagaceae/Nothofagus evolved largely as the South Pacific/Antarctic vicariant in the breakup of a world‐wide Fagales ancestor.  相似文献   

8.
The biogeography of Gunnera L.: vicariance and dispersal   总被引:2,自引:1,他引:1  
Aim The genus Gunnera is distributed in South America, Africa and the Australasian region, a few species reaching Hawaii and southern Mexico in the North. A cladogram was used to (1) discuss the biogeography of Gunnera and (2) subsequently compare this biogeographical pattern with the geological history of continents and the patterns reported for other Southern Hemisphere organisms. Location Africa, northern South America, southern South America, Tasmania, New Zealand, New Guinea/Malaya, Hawaii, North America, Antarctica. Methods A phylogenetic analysis of twenty‐six species of Gunnera combining morphological characters and new as well as published sequences of the ITS region, rbcL and the rps16 intron, was used to interpret the biogeographical patterns in Gunnera. Vicariance was applied in the first place and dispersal was only assumed as a second best explanation. Results The Uruguayan/Brazilian Gunnera herteri Osten (subgenus Ostenigunnera Mattfeld) is sister to the rest of the genus, followed sequentially upwards by the African G. perpensa L. (subgenus Gunnera), in turn sister to all other, American and Australasian, species. These are divided into two clades, one containing American/Hawaiian species, the other containing all Australasian species. Within the Australasian clade, G. macrophylla Blume (subgenus Pseudogunnera Schindler), occurring in New Guinea and Malaya, is sister to a clade including the species from New Zealand and Tasmania (subgenus Milligania Schindler). The southern South American subgenus Misandra Schindler is sister to a clade containing the remaining American, as well as the Hawaiian species (subgenus Panke Schindler). Within subgenus Panke, G. mexicana Brandegee, the only North American species in the genus, is sister to a clade wherein the Hawaiian species are basal to all south and central American taxa. Main conclusions According to the cladogram, South America appears in two places, suggesting an historical explanation for northern South America to be separate from southern South America. Following a well‐known biogeographical pattern of vicariance, Africa is the sister area to the combined southern South America/Australasian clade. Within the Australasian clade, New Zealand is more closely related to New Guinea/Malaya than to southern South America, a pattern found in other plant cladograms, contradictory to some of the patterns supported by animal clades and by the geological hypothesis, respectively. The position of the Tasmanian G. cordifolia, nested within the New Zealand clade indicates dispersal of this species to Tasmania. The position of G. mexicana, the only North American species, as sister to the remaining species of subgenus Panke together with the subsequent sister relation between Hawaii and southern South America, may reflect a North American origin of Panke and a recolonization of South America from the north. This is in agreement with the early North American fossil record of Gunnera and the apparent young age of the South American clade.  相似文献   

9.
The Southern Hemisphere has traditionally been considered as having a fundamentally vicariant history. The common trans-Pacific disjunctions are usually explained by the sequential breakup of the supercontinent Gondwana during the last 165 million years, causing successive division of an ancestral biota. However, recent biogeographic studies, based on molecular estimates and more accurate paleogeographic reconstructions, indicate that dispersal may have been more important than traditionally assumed. We examined the relative roles played by vicariance and dispersal in shaping Southern Hemisphere biotas by analyzing a large data set of 54 animal and 19 plant phylogenies, including marsupials, ratites, and southern beeches (1,393 terminals). Parsimony-based tree fitting in conjunction with permutation tests was used to examine to what extent Southern Hemisphere biogeographic patterns fit the breakup sequence of Gondwana and to identify concordant dispersal patterns. Consistent with other studies, the animal data are congruent with the geological sequence of Gondwana breakup: (Africa(New Zealand(southern South America, Australia))). Trans-Antarctic dispersal (Australia <--> southern South America) is also significantly more frequent than any other dispersal event in animals, which may be explained by the long period of geological contact between Australia and South America via Antarctica. In contrast, the dominant pattern in plants, (southern South America(Australia, New Zealand)), is better explained by dispersal, particularly the prevalence of trans-Tasman dispersal between New Zealand and Australia. Our results also confirm the hybrid origin of the South American biota: there has been surprisingly little biotic exchange between the northern tropical and the southern temperate regions of South America, especially for animals.  相似文献   

10.
鄱阳湖南矶山湿地自然保护区的外来入侵植物调查与分析   总被引:2,自引:1,他引:1  
为了解鄱阳湖南矶山自然保护区外来入侵植物的状况, 从2010 年至2014 年对外来入侵植物的物种种类、分布、传播等进行了调查。结果表明, 南矶山湿地保护区共有外来入侵植物32 种, 隶属于l8 科28 属, 其中菊科最多, 有8 种6 属;其次是苋科, 有4 种3 属, 绝大多数是草本植物;以原产地为美洲的最多, 有15 种, 其中来自北美的有9 种。对保护区造成严重危害的外来入侵植物有5 种, 分别为野燕麦(Avena fatua)、小飞蓬(Conyza canadensis)、野胡萝卜(Daucus carota)、裸柱菊(Soliva anthemifolia)和空心莲子草(Alternanthera philoxeroides), 危害较强的主要有7 种, 危害较轻的有20 种。对外来植物的入侵途径、规律与成因以及对生态环境造成的影响进行了讨论, 并提出了防治对策与建议。  相似文献   

11.
Peterson KR  Pfister DH 《Mycologia》2010,102(6):1398-1416
Cyttaria species (Leotiomycetes, Cyttariales) are obligate, biotrophic associates of Nothofagus (Hamamelididae, Nothofagaceae), the southern beech. As such Cyttaria species are restricted to the southern hemisphere, inhabiting southern South America (Argentina and Chile) and southeastern Australasia (southeastern Australia including Tasmania, and New Zealand). The relationship of Cyttaria to other Leotiomycetes and the relationships among species of Cyttaria were investigated with newly generated sequences of partial nucSSU, nucLSU and mitSSU rRNA, as well as TEF1 sequence data and morphological data. Results found Cyttaria to be defined as a strongly supported clade. There is evidence for a close relationship between Cyttaria and these members of the Helotiales: Cordierites, certain Encoelia spp., Ionomidotis and to a lesser extent Chlorociboria. Order Cyttariales is supported by molecular data, as well as by the unique endostromatic apothecia, lack of chitin and highly specific habit of Cyttaria species. Twelve Cyttaria species are hypothesized, including all 11 currently accepted species plus an undescribed species that accommodates specimens known in New Zealand by the misapplied name C. gunnii, as revealed by molecular data. Thus the name C. gunnii sensu stricto is reserved for specimens occurring on N. cunninghamii in Australia, including Tasmania. Morphological data now support the continued recognition of C. septentrionalis as a species separate from C. gunnii. Three major clades are identified within Cyttaria: one in South America hosted by subgenus Nothofagus, another in South America hosted by subgenera Nothofagus and Lophozonia, and a third in South America and Australasia hosted by subgenus Lophozonia, thus producing a non-monophyletic grade of South American species and a monophyletic clade of Australasian species, including monophyletic Australian and New Zealand clades. Cyttaria species do not sort into clades according to their associations with subgenera Lophozonia and Nothofagus.  相似文献   

12.
Aim The ectomycorrhizal (ECM) mushroom family Inocybaceae is widespread in north temperate regions, but more than 150 species are encountered in the tropics and the Southern Hemisphere. The relative roles of recent and ancient biogeographical processes, relationships with plant hosts, and the timing of divergences that have shaped the current geographic distribution of the family are investigated. Location Africa, Australia, Neotropics, New Zealand, north temperate zone, Palaeotropics, Southeast Asia, South America, south temperate zone. Methods We reconstruct a phylogeny of the Inocybaceae with a geological timeline using a relaxed molecular clock. Divergence dates of lineages are estimated statistically to test vicariance‐based hypotheses concerning relatedness of disjunct ECM taxa. A series of internal maximum time constraints is used to evaluate two different calibrations. Ancestral state reconstruction is used to infer ancestral areas and ancestral plant partners of the family. Results The Palaeotropics are unique in containing representatives of all major clades of Inocybaceae. Six of the seven major clades diversified initially during the Cretaceous, with subsequent radiations probably during the early Palaeogene. Vicariance patterns cannot be rejected that involve area relationships for Africa–Australia, Africa–India and southern South America–Australia. Northern and southern South America, Australia and New Zealand are primarily the recipients of immigrant taxa during the Palaeogene or later. Angiosperms were the earliest hosts of Inocybaceae. Transitions to conifers probably occurred no earlier than 65 Ma. Main conclusions The Inocybaceae initially diversified no later than the Cretaceous in Palaeotropical settings, in association with angiosperms. Diversification within major clades of the family accelerated during the Palaeogene in north and south temperate regions, whereas several relictual lineages persisted in the tropics. Both vicariance and dispersal patterns are detected. Species from Neotropical and south temperate regions are largely derived from immigrant ancestors from north temperate or Palaeotropical regions. Transitions to conifer hosts occurred later, probably during the Palaeogene.  相似文献   

13.
Four major austral continental distribution patterns are evident in pteridophytes. Twenty-two species are completely circum-Antarctic. Another 39 species are partially circum-Antarctic, occurring in Australasia (Australia and New Zealand) and Africa (including Madagascar) but not South America, while 29 are in Africa and South America but not Australasia, and 13 are in South America and Australasia but not Africa. Two hypotheses are considered as explanations for the patterns: continental drift following the breakup of Gondwana and long-distance dispersal. Fossil evidence indicates that the majority of pteridophyte families involved appeared after the southern continents had drifted apart, so long-distance dispersal is likely to explain the distribution of species in these families on now widely separated continents. For those families extant before the break-up, there is no indication in the fossil record that the species involved were present in Gondwana. Aspects of the ecology of the species that are partly or completely circum-Antarctic indicate that long-distance dispersal, rather than continental drift, is a likely explanation for the patterns.  相似文献   

14.
Nuclear ITS sequences and ISSR profiles provide evidence that Raoulia rubra is endemic to the Tararua Range in the southern part of the North Island of New Zealand. Populations in the South Island previously ascribed to R. rubra are better ascribed to R. eximia. Our findings suggest that glaciation of the central mountains of the South Island during the last ice age have had a major impact on the evolution of the South Island cushion Raoulia species in New Zealand. However, simple hypotheses accounting for the effect of Pleistocene climate change are insufficient to explain patterns of endemism in the group.  相似文献   

15.
Aim To reconstruct the biogeographical history of New World emballonurid bats (tribe Diclidurini). Although bats are the second most species‐rich order of mammals, they have not contributed substantially to our understanding of the historical biogeography of mammals in the Neotropics because of a poor fossil record. In addition, being the only group of mammals that fly, bats typically have large distributions with relatively few species endemic to restricted areas that are amenable to vicariant biogeographical approaches. Location Central and South America. Methods Phylogenetic analysis for comparing trees (PACT) is a new algorithm that incorporates all spatial information from taxon area cladograms into a general area cladogram. There were nine biogeographical areas identified in Central and South America for New World emballonurid bats. Molecular dating was used to incorporate the temporal aspect of historical biogeography. This method was compared with dispersal–vicariance analysis (DIVA), which assumes vicariance as the default mode of speciation. Results Of the 45 speciation events in a fully resolved phylogeny, eight that were hypothesized by DIVA as vicariance were considered by PACT as two peripheral isolations and six within‐area events. DIVA was less parsimonious because it required six more post‐speciation dispersal events in addition to the 73 hypothesized by PACT. DIVA reconstructed a widely distributed ancestor, suggesting that most dispersal events occurred earlier, whereas the ancestral area for PACT based on character optimization was the Northern Amazon, suggesting that dispersal events were more recent phenomena. Main conclusions The general area cladogram from PACT indicated that within‐area events, and not vicariance, provide the major mode of speciation for New World emballonurid bats. There was no biological evidence supporting or rejecting sympatric speciation in New World emballonurid bats. However, the geological history, combined with fluctuations in temperature and sea level, suggested within‐area speciation in a changing and heterogeneous environment in the Northern Amazon during the Miocene. This scenario is similar to the taxon‐pulse hypothesis of biotic diversification, which posits repeated episodes of range expansions and contractions from a stable core area such as the Guiana Shield within the Northern Amazon.  相似文献   

16.
Lingulate brachiopods are described from the Upper Cambrian - Lower Ordovician (Tremadoc-Arenig) of Scandinavia (Sweden, Denmark, and Norway), South Ural Mountains, northeastern Central Kazakhstan, and the southern Kendyktas Range in southern Kazakhstan. The faunas comprise a total of 56 species of which 20 are new these are assigned to 40 genera, of which the lingulids Agalatassia and Keskentassia , the siphonotretid Siphonotrerella. and the acrotretids Galinella, Longipegma, Ottenbyella, Akmolina, Mamatia, Sasyksoria , and Otariella are new. The new Subfamily Elliptoglossinae is proposed. The poorly known Cambrianardovician stratigraphy of the South Urals. northeastern Central Kazakhstan, and the southern Kendyktas Range is reviewed. Many sequences in these areas that were previously referred to the Upper Cambrian and Tremadoc can now be correlated with the lower Arenig Hunneberg Stage in Baltoscandia. Three main types of faunal assemblages can be distinguished: (1) the Broeggeria assemblage; (2) several microbrachiopod assemblages; and (3) the Leptembolon-Thysanotos assemblage. The Broeggeria assemblage is distributed world-wide in the Tremadoc of the southern Kendyktas Range, Scandinavia, Belgium, Great Britain, Canada, and Argentina, while the Leptembolon-Thysanotos assemblage is confined to the Arenig of an area surrounding the East European platform, including northern Estonia, Poland, Germany, Bohemia, Serbia, and the South Urals. The microbrachiopod assemblages are known mainly from the Upper Cambrian - Arenig of Scandinavia, South Ural Mountains, northeastern Central Kazakhstan, and the southern Kendyktas Range.  相似文献   

17.
The grass genus Hordeum (Poaceae, Triticeae), comprising 31 species distributed in temperate and dry regions of the world, was analysed to determine the relative contributions of vicariance and long-distance dispersal to the extant distribution pattern of the genus. Sequences from three nuclear regions (DMC1, EF-G and ITS) were combined and analysed phylogenetically for all diploid (20 species) and two tetraploid Hordeum species and the outgroup Psathyrostachys. Ages of clades within Hordeum were estimated using a penalized likelihood analysis of sequence divergence. The sequence data resulted in an almost fully resolved phylogenetic tree that allowed the reconstruction of intrageneric migration routes. Hordeum evolved c. 12 million years ago in South-west Asia and spread into Europe and Central Asia. The colonization of the New World and South Africa involved at least six intercontinental exchanges during the last 4 million years (twice Eurasia-North America, North America-South America, twice South America-North America and Europe-South Africa). Repeated long-distance dispersal between the northern and southern hemisphere were important colonization mechanisms in Hordeum.  相似文献   

18.
19.
The phylogeny of the Giant Pill-Millipedes, order Sphaerotheriida, is investigated using a new morphological character matrix comprising 89 characters. The majority of these characters are employed for the first time in millipedes. All trees obtained agree on the monophyletic status of the Sphaerotheriida and several of its tribes, each restricted to a modern land mass. The species from Madagascar displaying island gigantism do not form a monophyletic group. The classic division of Giant Pill-Millipedes into two families, Sphaerotheriidae and Zephronidae, was not reflected in the analysis. The genus Procyliosoma is the sister-group to all other Sphaerotheriida, rendering the family Sphaerotheriidae paraphyletic. A new family-level classification of Giant Pill-Millipedes, based on the current phylogeny, is introduced. The new family Procyliosomatidae contains only the genus Procyliosoma , distributed in Australia and New Zealand. The family Zephronidae remains unchanged, while the family Sphaerotheriidae now incorporates only the African Giant Pill-Millipede genera. All genera from southern India and Madagascar form a monophyletic group and are placed in the new family Arthrosphaeridae. The Malagasy genus Sphaeromimus is more closely related to the Indian Arthrosphaera species than to other genera from Madagascar. A biogeographical analysis identifies the group as a Gondwana taxon (with a notable absence from South America). The current phylogeny of Giant Pill-Millipede families mirrors perfectly the suggested break-up of Gondwana fragments 160–90 Ma. No evidence for a dispersal event could be found, highlighting the importance of Giant Pill-Millipedes as a potential model taxon.  相似文献   

20.
中国种子植物特有属起源的探讨   总被引:70,自引:9,他引:70  
本文根据文献和调查资料,对于中国种子植物特有属(包括半特有属)进行了统计分析,着重根据现知化石资料和一些代表科属的系统发生,结合它们的地理分布探讨了中国特有属的起源问题,初步获得6点结论。主要是中国植物区系的特有性很高,种子植物中含有321个特有属和10个特有科(皆包括半特有的),约占全国同类属数的10%。包括系统发生和地理分布的各种类群。裸子植物特有属多发生于白垩纪或更早,被子植物古特有属主要发生于晚白垩纪及第三纪各时期,新特有属多发生于新第三纪及其以后,秦岭以南亚热带至热带山地是大多数特有属的分布和分化中心或发源地。即各特有属科主要起源于华南古陆和古地中海东岸,喜马拉雅造山运动和青藏高原的隆起,对于中国特有属的形成、发展和分布有重要影响。  相似文献   

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