The Phytogeography of Caprifoliaceae s. str. with Its Implications for Understanding Eastern Asiatic Flora

The Caprifoliaceae s. str. as here defined consists of 4 tribes and 12 genera: Caprifolieae (Lonicera, Leycesteria), Linnaeeae (Symphoricarpos, Abelia, Zabelia, Linnaea, Dipelta, Kolkwitzia, Heptacodium ), Diervilleae (Diervilla, Weigela ), Triosteae (Triosteum). Based on chorology, fossil records and dominant woody habit, the family may be considered as a fairly old one and probably originated in the Late Cretaceous or the Early Tertiary. In the light of facts, such as a number of phylogenetic series of Abelia, Triosteum and Weigela occurring in east Asia, Heptacodium, endemic to East Asia, as a link between the tribe Caprifolieae and the tribe Linnaeeae, and existence in East Asia of a high percentage of both palaeoendemic genera and some neoendemics, East Asia seems to be the centerof diversity of the family. Six Eastern Asiatic endemic genera might be grouped under three categories, Heptacodium, Dipelta and Kolkwitzia as palaeoendemics, Weigela as active epibiotics, and Zabelia and Leycesteria as neoendemics. The above inferences are made only on the basis of three main attributes, systematic position of genera isolated or not, their geographical distribution continuous or discontinuous with the closest relatives and the degree of diversification of forms or distinction between species within a genus, without consideration of insufficient fossil records and cytological data.     

忍冬科(狭义)植物地理及其对认识东亚植物区系的意义

本文所谓狭义的忍冬科,包含4族、12属即忍冬族(忍冬属、鬼吹箫属),北极花族(毛核属,糯米条属、六道木属、北极花属、双盾木属、猬实属、七子花属),锦带花族(德维花属、锦带花属)和莛子？族(莛子？属)。基于它们的分布、化石资料和以木本为主的特性,忍冬科可认为是一个古老的科,可能起源于晚白垩纪或早第三纪。又基于以下事实：在东亚糯米条属、莛子？属和锦带花属中,可见到一系列的系统发育列;东亚特有的七子花属,是联系忍冬族和北极花族的一个中间纽带;东亚不但有较高比例的古特有属,还有一些新特有属;由此,我们认为东亚是该科的多样化中心。在化石和细胞学资料不充分的情况下,我们仅根据三个主要特征,如属的系统位置是否孤立,与近缘属的分布区是否间断及属内的分化类型的多寡和种间的区别是否明显,试图将6个东亚特有属归为三类：七子花属、双盾木属和猬实属作为古特有属,锦带花属作为活化了的古特有属,六道木属和鬼吹箫属作为新特有属。     

First fossil record of an East Asian endemic genus Sladenia (Sladeniaceae) from its modern range: Implications for floristic evolution and conservation biology

Fossil records of endemic plants play an important role in recognizing the floristic history of East Asia and thereby facilitate the conservation of plant diversity in the region. However, the fossil record of many extant East Asian endemic genera remains poorly documented thus far. Here, we report an infructescence fossil of an East Asian endemic genus, Sladenia (Sladeniaceae), from the early Miocene of southeastern Yunnan, China. The fossil is characterized by: (i) dichasial cymes; and (ii) flask‐shaped ovary with dense subparallel ribs on the surface extending from the base to the distal end of the united style. It represents the first fossil record of Sladenia in Asia, showing that the genus was established in the region at least by the early Miocene. Given that a much older fossil record of Sladeniaceae has been reported from Africa and the sister group of Sladenia is distributed only in Africa, Sladenia is not likely of East Asian origin. The present endemic status of Sladenia was possibly achieved by regional extirpation in Africa and taking refuge in East Asia. This case thus supports the “Museum” rather than “Cradle” hypothesis for the genesis of high plant species in the flora of East Asia. A comparison of the present fossil with extant Sladenia infructescence shows morphological stasis from the early Miocene to present. Such evolutionary tardiness might have resulted in the reduced fitness of the genus, which further caused its current endangered situation.     

中国蔷薇科绣线菊亚科的演化、分布——兼述世界绣线菊亚科植物的分布

绣线菊亚科是蔷薇科最原始的亚科,共有22属260余种, 包括常绿和落叶两大类群,前者是 原始类型。我国有8属100种,全都为落叶性。本文着重讨论中国各属的起源、演化和分布等 ,同时也概述全亚科植物在世界各植物区的分布等问题。绣线菊属Spiraea是该亚科落叶类群中最原始的属,它在早期发生趋异进化,衍生出形态各异而亲缘关系密切 的不同属,本文阐明了中国各属的系统位置和属间的亲缘关系。通过对我国各属地理分布的 分析对比,属的分布区可归纳为5个类型。对全球绣线菊亚科植物在世界各植物区中的属、种数统计表明,东亚区有8属105种,其中有96个特有种,是该亚科植物分布最多而又最集中 地区,具有在系统发育上处于各主要演化阶段的落叶类型,因此,东亚区是全球绣线菊亚科植 物的现代分布和分化中心,也是落叶类群发生和发展的关键地区。在北美洲,从马德雷区至落基山区一带分布着11属46种,均为特有种,显然北美洲西部也是该亚科植物的现代分布中心,但可能是第二分布中心。南美洲至今保存2个较古老的常绿属,即Quillaja和K ageneckia,基于此,南美洲可能是绣线菊亚科某些常绿属早期分化和发展的关键地区 。中国绣线菊亚科植物在东亚区占绝对优势,有8属82种,其中有62个特有种,分别占该区属 、种和 特有种数的100%、82%、和65%, 这些类群分布最密集地区是在中国喜马拉雅森林植物亚区 中的横断山脉地区和中国日本森林植物亚区的西部,这一带是中国绣线菊亚科的现代分布和多样性中心,很可能是某些属的发源地。由此看来,绣线菊亚科的落叶属可能起源于劳亚古陆。据化石记载,该亚科植物的起源时间可以追溯到白垩纪早白垩世。     

Regional environmental breadth predicts geographic range and longevity in fossil marine genera

Background

Geographic range is a good indicator of extinction susceptibility in fossil marine species and higher taxa. The widely-recognized positive correlation between geographic range and taxonomic duration is typically attributed to either accumulating geographic range with age or an extinction buffering effect, whereby cosmopolitan taxa persist longer because they are reintroduced by dispersal from remote source populations after local extinction. The former hypothesis predicts that all taxa within a region should have equal probabilities of extinction regardless of global distributions while the latter predicts that cosmopolitan genera will have greater survivorship within a region than endemics within the same region. Here we test the assumption that all taxa within a region have equal likelihoods of extinction.

Methodology/Principal Findings

We use North American and European occurrences of marine genera from the Paleobiology Database and the areal extent of marine sedimentary cover in North America to show that endemic and cosmopolitan fossil marine genera have significantly different range-duration relationships and that broad geographic range and longevity are both predicted by regional environmental breadth. Specifically, genera that occur outside of the focal region are significantly longer lived and have larger geographic ranges and environmental breadths within the focal region than do their endemic counterparts, even after controlling for differences in sampling intensity. Analyses of the number of paleoenvironmental zones occupied by endemic and cosmopolitan genera suggest that the number of paleoenvironmental zones occupied is a key factor of geographic range that promotes genus survivorship.

Conclusions/Significance

Wide environmental tolerances within a single region predict both broad geographic range and increased longevity in marine genera over evolutionary time. This result provides a specific driving mechanism for the spatial and temporal distributions of marine genera at regional and global scales and is consistent with the niche-breadth hypothesis operating on macroevolutionary timescales.     

Fossil preservation and the stratigraphic ranges of taxa

The incompleteness of the fossil record hinders the inference of evolutionary rates and patterns. Here, we derive relationships among true taxonomic durations, preservation probability, and observed taxonomic ranges. We use these relationships to estimate original distributions of taxonomic durations, preservation probability, and completeness (proportion of taxa preserved), given only the observed ranges. No data on occurrences within the ranges of taxa are required. When preservation is random and the original distribution of durations is exponential, the inference of durations, preservability, and completeness is exact. However, reasonable approximations are possible given non-exponential duration distributions and temporal and taxonomic variation in preservability. Thus, the approaches we describe have great potential in studies of taphonomy, evolutionary rates and patterns, and genealogy. Analyses of Upper Cambrian-Lower Ordovician trilobite species, Paleozoic crinoid genera, Jurassic bivalve species, and Cenozoic mammal species yield the following results: (1) The preservation probability inferred from stratigraphic ranges alone agrees with that inferred from the analysis of stratigraphic gaps when data on the latter are available. (2) Whereas median durations based on simple tabulations of observed ranges are biased by stratigraphic resolution, our estimates of median duration, extinction rate, and completeness are not biased.(3) The shorter geologic ranges of mammalian species relative to those of bivalves cannot be attributed to a difference in preservation potential. However, we cannot rule out the contribution of taxonomic practice to this difference. (4) In the groups studied, completeness (proportion of species [trilobites, bivalves, mammals] or genera [crinoids] preserved) ranges from 60% to 90%. The higher estimates of completeness at smaller geographic scales support previous suggestions that the incompleteness of the fossil record reflects loss of fossiliferous rock more than failure of species to enter the fossil record in the first place.     

亚洲土著类群硅藻鼠科的演化

硅藻鼠科是仅分布于亚洲的啮齿类类群,头骨具豪猪型咬肌结构,下颌则为松鼠型。该类群代表了一个从梳趾鼠类分化出的区域性支系,虽与豪猪次目相近,但并不是它的成员。最早的硅藻鼠化石记录发现于Baluchistan渐新世陆相地层中,稍晚的记录发现于南业晚渐新世。印度次大陆连续的地层为该科的演化历史提供了主要的化石依据。早中新世晚期至中中新世,硅藻科化石也发现了泰国、中国以及日本。其后的硅藻鼠种类少且鲜有化石记录。晚中新世早期在巴基斯坦有一个种,中国南部晚中新世也可能有一个种。尽管在最早的化石地点发现的标本较多,但其后的时段内除泰国李盆地外化石并不丰富,这指示了其特殊的生活习性或其生活区域化石保存的偏差。已知的化石记录并没有指示出该类群的多样性,也可能是缺少石化作用的结果。硅藻鼠类在水系外围区域延续生存与最近在老挝中部多岩石地带发现的现生Laonastes也是一个硅藻鼠的假设相一致。     

The Palaearctic centers of taxonomic diversity of fleas (Siphonaptera)

The Palaearctic flea fauna includes 921 species and 479 subspecies from 96 genera of 10 families. Of them, 858 species (94%) from 43 genera are endemic to the Palaearctic; they comprise 40% of the Palaearctic Hystrichopsyllidae, 24% of Ceratophyllidae, and 20% of Leptopsyllidae. Ranges of 581 species (63% of the Palaearctic fauna) are situated within one province or subregion of the Palaearctic. Species with ranges including a part of Asia (592) comprise 87% of the total fauna; 72% of the species (517) are endemic to the Palaearctic. The largest centers of taxonomic diversity of Palaearctic fleas are situated in the East Asian, Central Asian, and Turano-Iranian Subregions: 320 species of fleas (214 of them endemic) from 59 genera (8 endemic) are known from the East Asian Subregion; 270 species (over 120 endemic) from 54 genera (5 endemic) are distributed in the Central Asian Subregion. The Turano-Iranian fauna comprises 213 species (103 endemic) from 47 genera (3 endemic); about 160 species occur in the Turanian Subprovince closest to the Russian borders, one-third of them (52 species, or 33%) are endemic; 69 species more are endemic to the entire Asian part of the Palaearctic. Extra-Asian and extra-Siberian ranges are known in 190 flea species. In the western Palaearctic, 76 species are endemic to the European Province, and 57 species, to the Mediterranean Province; 36 species have Euro-Mediterranean distribution. The fauna of the Saharo-Arabian Subregion comprises 30 species (12 endemic), 6 species have ranges of the Mediterranean-Saharo-Arabian type. Scenarios of the origin of the Siphonaptera at the Triassic-Jurassic boundary are hypothesized. Formation of the Palaearctic flea fauna was mostly supported by the Asian-Indo-Malayan and East Asian-Western American palaeofaunal centers of taxonomic diversity. The long history of faunal exchange between the east Palaearctic and the west Nearctic is manifested by the distribution of the parasites of rodents and insectivores, fleas of the genera Stenoponia, Rhadinopsylla, Nearctopsylla, and Catallagia, belonging to several subfamilies of the Hystrichopsyllidae, as well as members of a number of other flea families. A great number of endemic species in the genera Palaeopsylla and Ctenophthalmus (Hystrichopsyllidae), both in the European and Asian parts of the Palaearctic, can be explained by the junction of the European and Asian continental platforms in the late Cretaceous and their subsequent isolation during the Paleocene. A considerable contribution to the flea fauna in the Russian territory was made by the East Asian-Nearctic center of taxonomic diversity, with a smaller role of the European palaeofauna. Immigration of species of the family Pulicidae from the Afrotropical Region is restricted to the southern territories of Russia.     

Geographical distribution and extinction risk: lessons from Triassic–Jurassic marine benthic organisms

Aim To evaluate the influence of geographical distribution on the extinction risk of benthic marine invertebrates using data from the fossil record, both during times of background extinction and across a mass‐extinction episode. Total geographical range is contrasted with proxies of global abundance to assess the relationships between the two essential components of geographical distribution and extinction risk. Location A global occurrence data base of fossil benthic macro‐organisms from the Triassic and Jurassic periods was used for this study. Methods Geographical distributions and biodiversity dynamics were assessed for each genus (all taxa) or species (bivalves) based on a sample‐standardized data set and palaeogeographical reconstructions. Geographical ranges were measured by the maximum great circle distance of a taxon within a stratigraphic interval. Global abundance was assessed by the number of localities at which a taxon was recorded. Widespread and rare taxa were separated using median and percentile values of the frequency distributions of occurrences. Results The frequency distribution of geographical ranges is very similar to that for modern taxa. Although no significant correlation could be established between local abundance and geographical range, proxies of global abundance are strongly correlated with geographical range. Taxon longevities are correlated with both mean geographical range and mean global abundance, but range size appears to be more critical than abundance in determining extinction risk. These results are valid when geographical distribution is treated as a trait of taxa and when assessed for individual geological stages. Main conclusions Geographical distribution is a key predictor of extinction risk of Triassic and Jurassic benthic marine invertebrates. An important exception is in the end‐Triassic mass extinction, which equally affected geographically restricted and widespread genera, as well as common and rare genera. This suggests that global diversity crises may curtail the role of geographical distribution in determining extinction risk.     

云南哀牢山国家级自然保护区蕨类植物区系地理研究

通过野外调查和资料整理分析,哀牢山国家级自然保护区共有蕨类植物48科,118属,446种(包括变种和变型)。优势科为鳞毛蕨科、水龙骨科和蹄盖蕨科,优势属为耳蕨属、蹄盖蕨属、鳞毛蕨属和卷柏属。区系分析结果表明:该蕨类区系是亚热带性质的区系;热带亚洲成分随着海拔的升高,比例逐渐降低,而中国-喜马拉雅成分随着海拔的升高逐渐增加;地理成分的东西坡差异不明显;该蕨类区系与喜马拉雅地区和热带亚洲的关系较密切,而与日本的关系较疏远;该蕨类区系具有较丰富的中国特有成分;哀牢山明显处于滇西北、滇东南这两大中国特有多样性中心之间,成为联系的纽带。     

Diverse fossil Onagraceae pollen from a Miocene palynoflora of north-east China: early steps in resolving the phytogeographic history of the family

The origin and evolution of angiosperms can be unravelled by using fossil records to determine first occurrences and phytogeographic histories of plant families and genera. Many angiosperm families, for example the Onagraceae, have a poor macrofossil record, but are more common in palynological records. Modern Onagraceae produce pollen clearly distinct from that of other angiosperms. Combined morphological features obtained by use of light and scanning electron microscopy have enabled assignment of fossil Onagraceae pollen to extant genera, and therefore tracing of the origin and past distributions of extant Onagraceae lineages. We studied a Miocene palynoflora from the Daotaiqiao Formation of north-east China. Using the single-grain technique, we examined individual Onagraceae pollen/tetrads using both light and scanning electron microscopy. Fossil Onagraceae pollen is more frequent than macrofossil remains, but is still rare, and usually represented by a single taxon in palynological samples. Remarkably, samples from the Miocene of north-east China contain five different species: two of Circaea, one of Epilobium, and two of Ludwigia. Such a large number of Onagraceae taxa from a single palynoflora is unknown elsewhere. Whereas Ludwigia pollen is known from Cenozoic sediments of the northern hemisphere, the Circaea pollen is the first fossil pollen assignable to this extant genus. This is also the first fossil record of Epilobium from China. Although the young geological age of this sample does not enable consideration of time of origin for the genera encountered, the co-occurrence of Circaea, Epilobium, and Ludwigia in the mid to late-Miocene of East Asia sheds some light on their phytogeographic histories.     

Curtisia (Cornales) from the Eocene of Europe and its phytogeographical significance

Fossil remains of Curtisia Aiton (Cornales) are recognized for the first time from the Tertiary of Europe, based on early Eocene anatomically preserved fruits from the London Clay and Poole Formations of southern England. The modern distribution of this monotypic genus is limited to the cape of South Africa. Curtisia quadrilocularis (Reid & Chandler) comb. nov. fruits have globose tetralocular endocarps composed of isodiametric sclereids with a single seed per locule, a prominent axial vascular canal, apical placentation, and four germination valves. All of these characters, as well as size, correspond to extant Curtisia . Although many fossil taxa from the Eocene of Europe have been shown to have their closest extant relatives in Asia, this occurrence of Curtisia highlights Tertiary floristic exchange between Europe and Africa. The newly recognized fossil occurrences suggest a Laurasian origin for Curtisia , in conformity with the fossil record for several other genera of the Cornales. In addition, our rejection of the former assignment of this species to Leucopogon causes us to question whether Epacridaceae were present in the Tertiary of Europe.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 127–134.     

The first Loranthaceae fossils from Africa

An ongoing re-investigation of the early Miocene Saldanha Bay (South Africa) palynoflora, using combined light and scanning electron microscopy (single grain method), is revealing several pollen types new to the African fossil record. One of the elements identified is Loranthaceae pollen. These grains represent the first and only fossil record of Loranthaceae in Africa. The fossil pollen grains resemble those produced by the core Lorantheae and are comparable to recent Asian as well as some African taxa/lineages. Molecular and fossil signals indicate that Loranthaceae dispersed into Africa via Asia sometime during the Eocene. The present host range of African Loranthaceae and the composition of the palynoflora suggest that the fossil had a range of potential host taxa to parasitise during the early Miocene in the Saldanha Bay region.     

试论中国种子植物特有属的分布区类型

中国种子植物特有属是局限分布于中国行政区域范围内的植物成分,就其分布特点看,集中分布于中国南部亚热带广阔区域。由于中国地域广袤,虽然大多数特有属分布在东亚自然地域范围内,但南部特有属的分布范围已进入古热带植物区的马来亚森林植物亚区的北部,而西部的特有属的分布范围已进入青藏高原地区。局限于不同地域分布的特有属,各自的起源发生、所经历的地质历史过程存在一定差别。本文以自然地理区划作为研究中国种子植物特有属分布区类型的依据,将中国特有属分布区类型划分为中国东部和中部特有分布变型、中国南部特有分布变型、中国西部特有分布变型和中国北部特有分布变型4类。其中中国南部特有分布变型所含特有属为热带区系成分,其它3个特有分布变型所含特有属为温带区系成分。这样能较客观地反映中国特有属的自然地理特征,有利于研究局部地区植物区系的地质历史演变过程。     

Biogeography of Old World emballonurine bats (Chiroptera: Emballonuridae) inferred with mitochondrial and nuclear DNA

Extant bats of the genus Emballonura have a trans-Indian Ocean distribution, with two endemic species restricted to Madagascar, and eight species occurring in mainland southeast Asia and islands in the western Pacific Ocean. Ancestral Emballonura may have been more widespread on continental areas, but no fossil identified to this genus is known from the Old World. Emballonura belongs to the subfamily Emballonurinae, which occurs in the New and Old World. Relationships of all Old World genera of this subfamily, including Emballonura and members of the genera Coleura from Africa and western Indian Ocean islands and Mosia nigrescens from the western Pacific region, are previously unresolved. Using 1833 bp of nuclear and mitochondrial genes, we reconstructed the phylogenetic history of Old World emballonurine bats. We estimated that these lineages diverged around 30 million years ago into two monophyletic sister groups, one represented by the two taxa of Malagasy Emballonura, Coleura and possibly Mosia, and the other by a radiation of Indo-Pacific Emballonura, hence, rendering the genus Emballonura paraphyletic. The fossil record combined with these phylogenetic relationships suggest at least one long-distance dispersal event across the Indian Ocean, presumably of African origin, giving rise to all Indo-Pacific Emballonura species (and possibly Mosia). Cladogenesis of the extant Malagasy taxa took place during the Quaternary giving rise to two vicariant species, E. atrata in the humid east and E. tiavato in the dry west.     

Sandstone rockhouses of the eastern United States,with particular reference to the ecology and evolution of the endemic plant taxa

Rockhouses are semicircular recesses extending far back under cliff overhangs that are large enough to provide shelter for humans. The largest sandstone rockhouses in the eastern United States are at the heads of gorges, and they are in stream valleys cut during the Pleistocene; most are formed in Mississippian and Pennsylvanian-age rocks. Compared to the surrounding environment, the interior of rockhouses is shaded, is warmer during winter and cooler during summer, and has lower evaporation rates and higher humidities. Water enters rockhouses primarily by groundwater seepage and by dripping from the ceiling. Soil consists mostly of sand with low pH, but high levels of some nutrients are associated with saltpeter earth and with ecofactual and artifactual remains left by human occupants during prehistoric time. Most plant taxa in sandstone rockhouses in eastern United States are native C₃ phanerophytes or hemicryptophytes, and similarities in species composition among rockhouses are low. Eleven plant taxa belonging to eight families of flowering plants and ferns are endemic or nearly endemic to sandstone rockhouses in eastern United States. Three endemics are restricted to the gorges of a single river, and only one taxon ranges far north of the Wisconsinan Glacial Boundary. The endemic ferns are Tertiary relicts derived from tropical taxa. The majority of endemic flowering plants are derived from temperate taxa that grow in habitats in the vicinity of rockhouses; their relative age ranges from Late Tertiary to the Recent. All the endemic taxa are perennial; two ferns occur as independent gametophytes. The endemic taxa of rockhouses are threatened primarily by disturbances associated with recreation.     

Fruit fossils of Rosoideae (Rosaceae) from the late Pliocene of northwestern Yunnan,Southwest China

The subfamily Rosoideae Focke (Rosaceae) has a good fossil record in the Northern Hemisphere, but these fossil records are confined mainly to a few genera, whereas the majority, in particular those with herbaceous members, are still under‐represented. In this study, we describe new fruit fossils of Rosoideae, including Fragaria achenes and Rubus endocarps, from the late Pliocene of northwestern Yunnan, Southwest China. These fossils add new accounts to the fossil archive of Rosoideae and provide the first fossil record of Fragaria in East Asia. The new fossil findings provide a historical backdrop for the modern diversity and distribution of the subfamily in northwestern Yunnan, a topographically complex area accommodating a high diversity for many plant groups. Our Rubus fossils, in combination with other nearby coeval occurrences of the genus, suggest that Rubus was already establishing its modern diversity in northwestern Yunnan during the late Pliocene. This finding enriches our knowledge of the post‐Neogene diversification of flowering plants in northwestern Yunnan, which is thought to be largely driven by dramatic mountain uplifts and environmental complications associated with the southeastern extension of the Tibetan Plateau.     

The impact of the Pull of the Recent on extant elasmobranchs

Modern elasmobranchs have a long evolutionary history and an abundant fossil record that consists mainly of teeth. Many fossil taxa have living representatives. However, the representation of extant taxa in the fossil record is unknown. To begin to understand the geological history of extant elasmobranchs, we here assess the quality of their fossil record. We do so by assessing the Pull of the Recent (POR). The POR can bias the fossil record because the rather complete record of living taxa allows palaeontologists to identify fossil members of the modern clades and to bridge time bins where fossils are absent. We assessed the impact of the POR by quantifying the proportion of extant elasmobranchs that have a fossil record, but do not occur in the last 5 million years (Pliocene and Pleistocene). We found that the POR does not affect orders and families, but it does affect 24% of elasmobranch genera. Within the different elasmobranch orders, the Lamniformes display the most complete generic fossil record, with no impact of the POR. Although modest, the impact of the POR in extant elasmobranch genera is higher than that found in other taxa. Overall, the geological history of elasmobranchs contradicts the usual assumption that the fossil record becomes worse backwards in time. This is the case across geographical regions and tooth size, further suggesting that sampling intensity and outcrop availability might explain the POR effect on sharks and rays.     

毛茛科金莲花亚科植物的地理分布

本文对毛茛科金莲花亚科各属的地理分布作了分析,该亚科植物除了少数属的一些种分布到南半球的温带地区,一些种分布或延伸到亚热带山地、非洲东部和北部的干旱、半干旱的地区外,绝大部分的属、种均分布于泛北极区域。根据其17个属的地理分布式样,把它们划分为8个分布区类型:(1)北温带分布类型4属;(2)北温带和非洲分布类型1属;(3)北半球温带和南半球间断分布类型1属;(4)欧洲和东亚间断分布类型1属;(5)西亚分布类型1属;(6)地中海分布类型3属;(7)欧亚和温带亚洲分布类型1属;(8)东亚分布类型5属。本文以形态特征为主,结合花粉和染色体的性状分析,认为东亚特有的鸡爪草属、Megaleranthis和铁破锣属可能分别是联系驴蹄草属和金莲花属,鸡爪草属和金莲花属以及金莲花族和升麻族的中间类型。另外,文中详细地统计了该亚科的不同等级分类群及特有种在各个植物区的分布,并从系统发育的观点讨论了各个植物区所具有的原始类群和进化类群,提出了如下论点,即东亚植物区(特别是中国西南部)不但是金莲花亚科植物分布的多度和多样性中心以及特有类群的分布中心,而且还是原始类群的保存中心,伊朗-土兰区及地中海周围是第二分布中心。     

The first representative Pliocene assemblages of passerine birds in Asia (Northern Mongolia and Russian Transbaikalia)

Passerine birds from two late Pliocene localities, Shaamar in northern Mongolia and Beregovaya in Transbaikalia (East Russia), represent the first known Neogene fossil assemblages of perching birds from Asia. A total of 11 families and 15 taxa are recognized, including a new genus and species of bunting, Pliocalcarius orkhonensis, apparently related to the Longspurs, and new species within the genera Hirundo and Rhodospiza, which are described. The avifauna is composed of open land and bush dwellers; it contains a few arid species, representing the oldest finds of the corresponding genera or lineages. This may indicate that the living Asian arid avian complex originated in Central Asia in the Neogene. Several genera (Rhodospiza, Paradoxornis) are documented in this paper for the first time in pre-Pleistocene deposits. Report of Calcarius is the first pre-Holocene evidence of the occurrence of this genus in Asia, which together with the remains of Synaptomys lemmings at Shaamar, illustrates faunal interchanges between North America and Asia in the Pliocene.