协同系统发生的研究方法

协同系统发生研究生态上相关群体的系统发生间的关系,其研究方法主要分为两类：基于事件法和整体拟合法.基于事件法包括布鲁克斯简约分析、组分分析、协调树分析等,此类方法考虑进化情境,逻辑性强,但分析结果过多,较难选择;整体拟合法考虑了系统发生的误差,提供较好的关系一致性,但缺乏联系进化情境.本文详细比较了两类方法下各种分析软件的优劣,提出了整合两类方法的可能性,以便更好地理解协同系统发生.     

Species richness and complementarity of beetle faunas in a mediterranean-type biodiversity hotspot

Regions of mediterranean-type climate represent most extra-tropical biodiversity hotspots, being both highly diverse and highly endangered. Though renowned for their plant richness, these regions’ insects constitute the bulk of their alpha diversities. Data on insect distribution and rarity are generally lacking for such regions, and are often considered unattainable. Intensive field inventories combined with statistical extrapolation methods can provide a sufficient understanding of alpha, beta, and gamma diversity components for application to conservation planning. These are essential to assessing the adequacy of a regional reserve network for the conservation of insect diversity. Here the beetle faunas of three protected areas spanning three major ecoregions in the California Floristic Province were inventoried and analyzed for species richness, complementarity, and uniqueness. These surveys produced collectively nearly 1,200 species from all three sites, estimated to be about 80% of their total faunas. Diversity was highly partitioned among sites, no one site containing more than 60% of the species. Dissimilarity was moderate to high for all comparisons, and all sites contained >40% unique species. Comparison of these results with those based on species of co-occurring plants reveal incongruent species richness but congruent similarities among sites. These results provide quantitative support to the perception that mediterranean insect faunas show high spatial variability. Along with online specimen level data on distribution, rarity, and seasonality, these results will help speed the incorporation of insect data into serious conservation planning.     

Species richness and endemism in the Western Australian flora

Aim Estimates of endemic and non‐endemic native vascular plant species in each of the three Western Australian Botanical Provinces were made by East in 1912 and Beard in 1969. The present paper contains an updated assessment of species endemism in the State. Location Western Australia comprises one third of the continental Australian land mass. It extends from 13° to 35° S and 113° to 129° W. Methods Western Australia is recognized as having three Botanical Provinces (Northern, Eremaean and South‐West) each divided into a number of Botanical Districts. Updated statistics for number of species and species endemism in each Province are based on the Census of Western Australian Plants data base at the Western Australian Herbarium ( Western Australian Herbarium, 1998 onwards). Results The number of known species in Western Australia has risen steadily over the years but reputed endemism has declined in the Northern and Eremaean Provinces where cross‐continental floras are common. Only the isolated South‐West Province retains high rates of endemism (79%). Main conclusions With 5710 native species, the South‐West Province contains about the same number as the California Floristic Province which has a similar area. The Italian mediterranean zone also contains about this number but in a smaller area, while the much smaller Cape Floristic Region has almost twice as many native species. The percentage of endemic species is highest at the Cape, somewhat less in south‐western Australia and less again in California. Italy, at 12.5%, has the lowest value. Apart from Italy, it is usual for endemism to reach high values in the largest plant families. In Western Australia, these mainly include woody sclerophyll shrubs and herbaceous perennials with special adaptations to environmental conditions. While those life forms are prominent in the Cape, that region differs in the great importance of herbaceous families and succulents, both of which are virtually absent from Western Australia. In California and Italy, most endemics are in families of annual, herbaceous perennial and soft shrub plants. It is suggested that the dominant factor shaping the South‐West Province flora is the extreme poverty of the area’s soils, a feature that emphasizes sclerophylly, favours habitat specialization and ensures relatively many local endemic species.     

秦岭和黄土高原地区锦鸡儿属的表征,分支和生物地理学的探讨

选用锦鸡儿属在秦岭和秦岭以北的２０余种和５９个形态性状作为分析基础。表征图和分支图共同提示出羽状和掌状叶类群形成两大类。分支图说明了树锦鸡儿Ｃ．ａｒｂｏｒｅｓｃｅｎｓ和柄荚锦鸡儿Ｃ．ｓｔｉｐｉｔａｔａ等为原始类群。沿树锦鸡儿的分布区,本属植物向西和西南方向适应辐射成以温度和降水为主导因子的生态序列：（１）森林种→森林草原种→草原种→荒漠种,森林种→高寒山地种;（２）湿润地带→亚湿润地带→半干旱地带     

Phylogeography of the piranha genera Serrasalmus and Pygocentrus: implications for the diversification of the Neotropical ichthyofauna

The phylogenetic relationships within the piranhas were assessed using mitochondrial sequences with the aim of testing several hypotheses proposed to explain the origin of Neotropical diversity (palaeogeography, hydrogeology and museum hypotheses). Sequences of the ribosomal 16S gene (510 bp) and control region (980 bp) were obtained from 15 localities throughout the main South American rivers for 21 of the 28 extant piranha species. The results indicate that the genus Serrasalmus is monophyletic and comprises three major clades. The phylogeographical analyses of these clades allowed the identification of five vicariant events, extensive dispersal and four lineage duplications suggesting the occurrence of sympatric speciation. Biogeographical patterns are consistent with the prediction made by the museum hypothesis that lineages from the Precambrian shields are older than those from the lowlands of the Amazon. The vicariant events inferred here match the distribution of the palaeoarches and several postdispersal speciation events are identified, thereby matching the predictions of the palaeogeography and hydrogeology hypotheses, respectively. Molecular clock calibration of the control region sequences indicates that the main lineages differentiated from their most recent common ancestor at 9 million years ago in the proto Amazon-Orinoco and the present rate of diversification is the highest reported to date for large carnivorous Characiformes. The present results emphasize that an interaction among geology, sea-level changes, and hydrography created opportunities for cladogenesis in the piranhas at different temporal and geographical scales.     

河南省水生种子植物的生物多样性及区系特征

论述了河南省水生种子植物的生物多样性及区系组成。结果表明,河南水生种子植物有30科、61属、125种、1亚种、9变种及2变型,其中以挺水植物为主,有75种、1亚种、5变种、2变型;浮水植物次之,有33种2变种;沉水植物较少,有17种2变种。河南省水生植物的区系成分中,以泛热带、北温带和旧世界热带3种成分为主,其次是东亚和东亚北美间断成分和旧世界温带成分,植物区系中热带成分和温带成分几乎并重。     

A new species of Sanicula L. (Umbelliferae/Apiaceae) endemic to Baja California, Mexico

A new species of the genusSanicula (sect.Sanicoria) endemic to the southern Sierra Juárez of Baja California, Mexico, is described and illustrated.Sanicula moranii resemblesS. deserticola andS. bipinnatifida, but has thicker basal leaves, with broader petioles and rachises, and shorter fruit prickles that are confined to the apical part of the mericarps. The taxonomic relationships of these species are discussed, along with aspects of their distribution and habitat.

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Resumen  Una neuva especie del géneroSanicula (secciónSanicoria) endémica de la Sierra Juárez de Baja California, México, es descrita e ilustrada.Sanicula moranii presenta similitud conS. deserticola yS. bipinnatifida, no obstante tiene gruesas hojas basales con pecíolos y raquis anchos, y espínulas del fruto más cortas que se distribuyen únicamente en la parte apical de los mericarpos. Además, se comentan las relaciones taxonómicas de las tres especies, así como algunos aspectos de sus distribuciones y hábitats.