Revision of the Genera Thyca, Stilifer, Scalenostoma, Mucronalia and Echineulima (Mollusca, Prosobranchia, Eulimidae)

All species that have been described of the genera mentioned in the title are listed and their systematic position given. The species of Stilifer (with 11 species, including S. inflatus sp.n. and 5. concavus sp.n.) are parasites of starfishes. Scalenostoma (3 species) are parasites of stone corals. Thyca (with 8 species) is removed from Capulidae, and included in Eulimidae. T. hawaiiensis sp.n. is described. The species of Thyca are parasites of starfishes. The species of Mucronalia (including M. trilineata sp.n.) are probably parasites of ophiuroids and Echineulima (with 4–6 species, including E. ponderi sp.n.) are parasites of echinoids. All species are figured, their characteristics are given and their host species and distributions are listed. Keys are given to the species of each genus, except Mucronalia. The genera Stilimella Laseron and Hyperlia Pilsbry are synonymized with Scalenostoma and the genera Kiramodulus Kuroda, Granulithyca Habe and Bessomia Berry are considered subgenera of Thyca.     

广州市萝岗区风水林植物组成及群落结构分析

通过野外实地调查,对广州市萝岗区风水林的植物组成及群落结构进行了分析.结果表明:萝岗区单个风水林面积为40 ～600 hm2,共有维管植物112科255属387种;其中,蕨类植物15科21属35种,裸子植物1科1属2种,被子植物96科233属350种;草本和乔木种类较多,分别有122和111种;灌木和藤本种类较少,分别有84和70种;其中,包含国家级珍稀保护植物5种和一些需要关注的种类,以及林下凤尾蕨(Pteris grevilleana Wall.ex Agardh)和虎克鳞盖蕨[Microlepia hookeriana (Wall.) Presl]2种广州市新记录种.优势科较明显,包含茜草科(Rubiaceae)、菊科(Compositae)、大戟科(Euphorbiaceae)、禾本科(Poaceae)、蝶形花科(Papilionaceae)、樟科( Lauraceae)等;虽然寡属科和寡种科所占比例较大,但包含种数较少;寡种属所占比例较大,占总属数的90.59％.植被类型属于南亚热带季风常绿阔叶林,以南亚热带常绿树种为主,可分为乔木层、灌木层和草本层,层间有丰富的藤本植物;作为群落的主体结构,木本植物较草本植物有优势.群落优势建群种主要为樟科、大戟科、壳斗科(Fagaceae)、山茶科(Theaceae)、胡桃科(Juglandaceae)和苏木科(Caesalpiniaceae)等科的种类,依据优势种不同可划分为13个群系.根据调查结果,对广州市萝岗区风水林的保护和资源利用提出了建议.     

Methods for monitoring threatened bryophytes

Monitoring is an indispensable tool for assessment of the state of species both locally and globally. The monitoring of bryophyte species has started quite recently and there is need for uniform methods that can be applied in different countries to get comparable results to give a basis for more effective species conservation. Here we present three general monitoring methods that are suitable for all European bryophytes. The method of permanent squares is used for long-lived species inhabiting stable communities on the ground or large rocks. The method of counting separated substrate units is used for species inhabiting tree trunks, boulders or large pieces of decaying wood. The method of sampling is used for short-lived species in unstable communities and for species that are difficult to identify with a hand-lens. The selection of species and sites to be monitored is discussed. Assessment of the current conservational state of the species depends on the state of habitats at monitoring plots that are defined through character and rate of threats, and change of population size compared with previous and first monitoring events. The three monitoring methods are illustrated with examples based on Estonian monitoring experiences. Suggestions of monitoring methods for bryophyte species belonging to the EU Habitat Directive are given.     

Chromosome Studies of 10 Species of Aconitum in China

This paper deals with chromosomal numbers and morphology of 10 species of Aconitum in China. According to the basic number of the genus (x=8), these species can be referred to diploid, tetraploid, hexaploid and octoploid. Correlation is found between chromosomal numbers, sizes and structures. The perennial species with a rhizome are mostly diploid, with chromosomes larger than those in the biennial species with a tuber, and their chromosome pairs 3-7 are mostly subterminal ones, whereas most biennial species are polyploid, and their chromosome pairs 3-7 are almost submetacentric. The evolutionary trends of chromosome from diploid to polyploid, large to small, st to sm are considered possible. The data are agreed with the idea that rhizomal species are more primitive than tuberous ones. The existence of two types of karyotypes in these 10 species is a further support of taxonomic division of two subgenera, subgen. Paraconitum and subgen. Aconitum. In addition, some species are taxonomically discussed.     

The Geographical Distribution and Floristic Composition of the Orchids in the Gongga Mountain Region,Sichuan

The Gongga Mountain Region, located on the eastern fringe of QinghaiXizang Plateau and at the north-eastern end of Hengduan Mountains, is one of the well-known large mountain areas in Sichuan Province. There are forty five high peaks with the elavation of 6000 m or over in the area, among which the Gongga Mountain is the highest one, with its summit being at the altitude of 7556 m, whereas the Dadu River Valley in the eastern part of the area is only 1150 m above sea level; The relative height in the region is thus about 6400 m. As we know so far the orchids in Gongga Mountain Region comprise 34 genera and 75 species with 1 variety, of which 12 species are epiphytes, 59 species with 1 variety terrestrials and 4 species saprophytes (Table 1.). I. The geographical distribution in the Gongga Mountain Region. The vertical distribution of the orchids in the area. Eastern flank: There are 39 species with I variety of orchids at 1150-2300 (-2400) m alt. in the subtropical evergreen broadleaf forest zone, of which 12 species, such as Bulbophyllum andersonii, Dendrobium hancockii, Otochilus porrecta, etc., are epiphytic (including a semiepiphyte, Pleione bulbocodioides), 25 species with 1 variety, such as Bletilla formosana, Calanthe davidii, Cypripedium henryi, etc., are terrestrial, and 2 species are saprophytic (i.e. Gastrodia elata and Neottia listeroides), the upper limit of the real epiphytic orchids is 1800 m alt. At the altitude 2300(-2400)-3600 (-3800) m, in the coniferous forest zone, found are 23 species, including 20 terrestrial species with 1 variety, such as Amitostigma gonggashanicum, Calanthe fimbriata, Coeloglossum viride, etc., 2 saprophytic species (Neottia acuminata and Risleya atropurpurea) and one semiepiphytic species. There are only 2 terrestrial species (i.e. Cypripedium tibeticum and Orchis chusua) at 3600(-3800)-4000m alt., in alpine shrub zone, the upper limit of the terrestrial orchids being 4000 m alt. At 4000-4400 m alt., in alpine meadow zone no orchids have so far been found. Western flank: There are 14 species of orchids, such as Habenaria limprichtii, Hemipilia flabellata, Satyrium ciliatum, etc., at 2300-2800 m alt., in the river valley shrub zone, and they all belong to the terrestrial orchids. At the altitude of 28003800m, in the coniferous forest zone found are 19 species of orchids, among which 18 species are terrestrial (such as Amitostigma monanthum, Cephalanthera longifolia, Peristylus coeloceras, etc.) and one is saprophytic. There are only 4 species of terrestrial orchids (i.e. Cypripedium tibeticum, Gymnadenia orchidis, Orchis chusua and O. diantha) at 3800-4800 m alt., in the alpine shrub-meadow zone, the upper limit of vertical distribution of terrestrial orchids being 4400 m alt. Twelve species here are common to the eastern flank. II. The floristic composition of orchids in Gongga Mountain Region. 1. Twenty three species, belonging to 13 genera, are widespread in Whole EastAsian Region. 2. Eight species, belonging to 8 genera, are the elements of the Sino-Japanese Subregion. 3. Forty one species with 1 variety, belonging to 24 genera, are the elements of the Sino-Himalayan Subregion, more than five times the elements of the Sino-Japanese Subregion. 4. The floristic features of the orchids in the area. (1) The floristic elements are mainly temperate and subtropical ones. (2) The life form is mostly terrestrial. (3) The species endemic to China are prolific (35 species with 1 variety, belonging to 18 genera, are endemic to China, and 26 species with 1 variety are distributed in south-western China and its adjacent region; Amitostigma gonggashanicum is endemic to the area). The floristic composition of orchids in the area is characterized by the dominance of terrestrial species and temperate and subtropical East-Asian elements, though with a few Indo-African tropical elements (such as genus Satyrium (1 species) ). In conclusion, it may be considered that the species of orchids are abundant and floristic elements are comparatively complex in the Gongga Mountain Region.     

Hypothesis: the rate and scale of dispersal of freshwater diatom species is a function of their global abundance

We have analysed the geographical records of a representative selection of extant diatom species from a freshwater pond. The more often a species is recorded in the ecological literature, the greater is its apparent global distribution. One explanation is that the frequently recorded species are globally abundant, whereas species that are infrequently recorded are globally rare. We suggest a model in which random dispersal is the dominant force driving large-scale distribution of species, with the rate and scale of dispersal largely determined by global population size. Thus species that are locally rare or abundant are likewise rare or abundant worldwide. It is predicted that many of the rarer diatom species will, with additional sampling effort, be shown to have wide geographical distribution, but this requires intensive studies focused on revealing species that are normally cryptic. The argument in favour of endemic diatom species is untenable, because it is not possible to disprove their existence elsewhere in the biosphere.     

海南种子植物科属与邻近地区科属关系的初步研究

<正> 一、前言 本文以海南野生种子植物的科属与越南、菲律宾、澳大利亚和我国台湾,广东(雷州半岛)等地的植物科属统计数字和属相似性,试图探讨它们之间的相似关系,对今后引种驯化和研究华南植物区系有一定的参考作用。     

六种鼠乳酸脱氢酶和超氧化物歧化酶位点变异的研究

用电泳比较分析了鼠科动物６个种的组织ＬＤＨ同工酶的Ａ、Ｂ、Ｃ亚基和ＳＯＤ同工酶位点的种属差异。结果表明,ＬＤＨ的Ａ和Ｂ亚基在进化上的可变性程度不同。在被分析的２个属共６种鼠中,首次发现Ｂ亚基的结构具有属的特征,同属的鼠种Ｂ亚基泳动度相同,在垂直凝胶电泳板上处于同一泳动线上。不同属的鼠其Ｂ亚基泳动度不同,家鼠属的鼠Ｂ亚基比姬鼠属的泳动快;Ａ亚基的结构既有属的特性,更具有种的特征,同属不同种的鼠Ａ亚基泳动速度不同,表现为ＬＤＨ同工酶带的间距不同。ＬＤＨ的Ｃ亚基结构因鼠种不同而异,由Ｃ亚基组成的ＬＤＨ－Ｘ带黄毛鼠位于自身的ＬＤＨ－３和ＬＤＨ－４之间,社鼠和褐家鼠此带位于自身的ＬＤＨ－４和ＬＤＨ－５之间,白腹巨鼠此带位于自身的ＬＤＨ－５以外的阴极端,与黑线姬鼠此带的位置特征相同。ＳＯＤ同工酶带只表现种的差异,其３条带泳动速度的改变具有协同而变的共同特点。被分析的鼠种经配对法比较生化特征的相同程度,初步表明黄毛鼠亲缘上与褐家鼠比较近,白腹巨鼠亲缘上又比其余３种鼠更近于姬鼠属。     

Co-occurrence of species with various geographical ranges, and correlation between area size and number of species in geographical scale

Co-occurrence of species of various geographical ranges is important to correct endemism evaluation. This co-occurrence is shown as non-hazardous. Influence of area size on species richness is assumed to be different with respect to endemic and non-endemic species. The territory of Israel and Sinai is subdivided into twenty biotic provinces. We segregated three hundred and twenty-five tenebrionid species inhabiting this territory into endemic, regional and ubiquitous species. Regression of the number of endemic species on the number of regional species is non-linear. Two distinct regression lines correspond to hot and cool areas. The number of ubiquitous species depends positively on numbers of both endemic and regional species, and negatively on their product. Ubiquitous species are predominantly synanthropic, and inability to tolerate competition with other tenebrionids is assumed as the basis of numerical relationships with other species. Correlation between numbers of endemic and non-endemic species of bird and mammal and size of area is analysed at the broad geographical scale. Relationships between area size evaluation and the numbers of endemic and non-endemic species are always different. The square root of the area km² is always more important in species richness determination than area itself. This variable is a linear characteristic of the area and its significance is discussed. Possible ecological interactions between species of various geographical ranges are also considered. A new method of evaluation of the level of faunal endemism is proposed.     

What do the biodiversity experiments tell us about consequences of plant species loss in the real world?

Experiments where the diversity of species assemblage is manipulated are sometimes used to predict the consequences of species loss from real communities. However, their design corresponds to a random selection of the lost species. There are three main factors that limit species richness: harshness of the environment, competitive exclusion, and species pool limitation. Species loss is usually caused by increasing effects of these factors. In the first two cases, the species that are excluded are highly non-random subsets of the potential species set, and consequently, the predictions based on random selection of the lost species might be misleading. The data show that the least productive species are those being recently excluded from temperate grasslands and consequently, species loss is not connected with decline of productivity. The concurrent species loss in many communities, however, means also a reduction of the available diaspore pool on a landscape scale, and could result in increased species pool limitation in other communities.     

Species: the concept, category and taxon

The term species by itself is vague because it refers to the species concept, the species category and the species taxon, all of which are distinct although related to one another. The species concept is not primarily a part of systematics, but has always been an integral part of basic biological theory, It is based on evolutionary theory and applies only to sexually reproducing organisms. The species concept and the phyletic lineage concept are quite distinct although they are related to one another. The important aspect of the species concept is lack of gene flow between different species, and hence the defining criterion of the species is genetic isolation. The species concept is often considered as non‐dimensional, both in time and space. Species possess three different major properties, namely genetic isolation, reproductive isolation and ecological isolation; these properties evolve at different times and under the effect of different causes during the speciation process. Speciation requires an external isolating barrier during the initial allopatric phase in which genetic isolation evolves and must reach 100% efficiency. The subsequent sympatric phase of speciation occurs after the disappearance of the external isolating barrier when members of the two newly evolved species can interact with one another and exert mutual selective demands on one another. Much of the reproductive and ecological isolation evolves during this secondary sympatric phase. The species category is a rank in the taxonomic hierarchy and serves as the basis on which the diversity of organisms is described; it is not the same as the species concept. The species category applied to all organisms, sexually and asexually reproducing. The species taxon is the practical application of the species category in systematics with the recognition of species taxa requiring many arbitrary decisions. No single set of rules exist by which the species category can be applied to all organisms. Recognition of species taxa in asexually reproducing organisms is based on amount of variation and gaps in the variation of phenotypic features associated with ecological attributes of these organisms as compared with similar attributes in sympatric species taxa of sexually reproducing organisms. Species taxa are multidimensional in that they exist over space–time and often have fuzzy borders. Because recognition of species taxa, including those in sexually reproducing organisms, depends on many arbitrary decisions especially when dealing with broad geographical and temporal ranges, species taxa cannot be used as the foundation for developing and testing theoretical concepts in evolutionary theory which can only be done with the non‐dimensional species concept.     

外来种隐蔽入侵： 类型及影响

隐蔽入侵（cryptic invasion）是指在形态上与土著种（或早期建群种）不能或难以区分的外来种在人们未觉察的状态下成功入侵的过程。人们对这类入侵方式往往视而不觉。本文综述了外来种隐蔽入侵的类型以及生态影响。隐蔽入侵的类型主要包括外来姊妹种形式的隐蔽入侵、 不同遗传支系的隐蔽入侵、 不同地理种群的隐蔽入侵以及“返传入”。其中, “返传入”目前还是一种假说。由于这类入侵外来种更容易与土著种（或早期建群种）杂交或基因渗透, 因而可对入侵种自身或土著种产生深远的生态影响。鉴于隐蔽入侵现象的广泛性, 建议进一步加强该方面的研究。     

Cytological study on the genus Syncalathium (Asteraceae-Lactuceae), an endemic taxon to alpine scree of the Sino-Himalayas

Cytological characters of four species in Syncalathium (Asteraceae: Lactuceae), a small genus with six identified species endemic to alpine scree of the Sino-Himalayan region, are surveyed in this report. Three species ( Syncalathium pilosum, Syncalathium chrysocephalum, and Syncalathium disciforme ) are examined for the first time. Combined with our previous counts, five species have been cytologically investigated from the genus and the results indicated that all species are diploid with the basic somatic chromosome number of x=8. The karyotype asymmetry of Syncalathium souliei is 2A, distinct from the other four species of 1 A, and the remaining species are divided into two subgroups with different karyotypes, consistent with their morphological features. The significance of the cytological evolution of Syncalathium is briefly discussed.     

New species, phylogeny, host-associations and geographic distribution of genus Cryptosporella (Gnomoniaceae, Diaporthales)

The phylogeny of Cryptosporella is revised to include recently discovered species. Eight species new to science are described and two new combinations are proposed, raising the total number of species accepted in Cryptosporella to 19. The species delimitation and phylogeny for Cryptosporella are determined based on analyses of DNA sequences from three genes (β-tubulin, ITS and tef1-α), comparative morphology of sexual structures on their host substrate, and host associations. The inferred phylogeny suggests that Cryptosporella has speciated primarily on Betulaceae with 16 species occurring on hosts in that plant family. The host range of most species seems to be narrow with nine species reported from a single host species or subspecies and seven species occurring on plants within a single host genus. A key to species is provided. The known distribution of Cryptosporella is expanded to mountain cloud forests of the provinces of Chiriquí in Panama and Tucumán in Argentina.     

The taxonomy, biogeography and host plant relationships of jumping plant-lice (Hemiptera: Psyllidae) associated with creosote bushes (Larrea spp., Zygophyllaceae)

Abstract.  The Neotropical genus Panisopelma (Psyllidae: Aphalaroidinae) is revised and its internal phylogeny analysed. The constituent species, including five new ones, are described and illustrated. Keys are provided for the adults and the last instar larvae. Eight species are associated with creosote bushes ( Larrea , Zygophyllaceae): five with L. nitida and three with L. divaricata . There is evidence that another three species, the larvae of which are unknown, also develop on L. divaricata . Seven species are restricted to Argentina, one to Bolivia and three to Chile. The cladistic analysis based on male, female and larval morphological characters yielded a single most-parsimonious tree. The species associated with L. nitida form a monophyletic clade, those on L. divaricata , by contrast, are paraphyletic. One clade with three species is restricted to Argentina, but three clades each contain a species from Argentina and Chile. Although a close association exists between Panisopelma and Larrea , there is no evidence for cospeciation, but rather an initial shift from an unknown host to L. divaricata and a second shift from L. divaricata to L. nitida . In three species pairs of Panisopelma , the distribution patterns suggest geographical vicariance between Argentina and Chile.     

云南毛翅目昆虫区系研究

云南已知毛翅目昆虫２４科７７属３２１种,含云南特有种１５２种。其中东洋界分布成分占８３％,东洋－古北界东部共布成分占９％,东洋－古北界西部共布、东洋－非洲界共布和广布成分所占比例均小于４％。云南毛翅目在我国的分布以西南型（４４％）、华南型（２１％）和西南－华南共布型（９％）为主,其次为向东扩散的西南－华南－华中（５％）和华南－华中（４％）共布型。云南与毗邻省四川的毛翅目区系关系最密切,其次是西藏和     

陕北黄土高原蒿属植物的分类与分析

陕北黄土高原有蒿属植物30种1变种,居该地产种子植物属中所含种数的首位。所产蒿属植物在不同的植被带中梯度变化明显,替代现象显著。在生态类型上,旱生类型从南向北递增,中生类型从南向北递减。在区系组成上可分为6种分布区类型,即:我国特有分布,3种;温带亚洲分布,14种1变种;北温带及中亚分布各4种;旧世界温带分布,3种;东亚分布的2种。可见陕北黄土高原蒿属植物种类丰富,梯度变化明显,旱化现象显著,地理成分复杂,但以温带亚洲分布类型为主,兼有其它成分,属典型的温带性质。     

黄土高原马栏林区主要植物种的生态位研究

应用L ev ins、Shannon-W iener生态位宽度公式和P ianka生态位重叠公式,定量研究了黄土高原马栏林区主要植物种的生态位宽度和生态位重叠特征,同时对主要种在演替系列上的生态位变化规律进行了分析.结果表明,在该地区森林群落演替系列中,乔木种生态位宽度的平均水平小于灌木种,建群种的生态位宽度小于主要伴生种;生态位宽度较大的种与其它各物种间生态位重叠的平均值较大,生态位宽度较小的种则相反,甚至没有重叠.由于物种生物生态学特性的不同和环境的异质性,具较宽生态位的物种间的生态位重叠也可能较小,生态位宽度较窄的物种间也可能有较大的生态位重叠,同属植物种对间也存在生态位重叠较大的情况.主要乔木和灌木种的生态位特征反映了森林群落演替的变化规律,该地区呈现出以自然恢复为主,同时又伴随着人为干扰的森林群落次生演替系列.