Distribution, hybridization and variation in the Israeli landsnail Levantina (Pulmonata: Helicidae)

The rock-dwelling landsnail Leuantinu is represented in Israel by two species, caesareana and hierosolyma . They are both found abundantly in Mediterranean, steppe, semi-arid and extremely arid habitats, and are probably ancient elements in the Israeli fauna. Their common borderline shows no association with altitude, rainfall, temperature, climatic zones, lithology, phytogeography, or the distribution of predators. The possiblity that one species is actively displacing the other, and that the position of the borderline is temporary, is rejected on grounds both of previous research and of fossil finds.
A narrow hybrid zone occurs in most places along the borderline. Laboratory experiments show that these hybrids are inferior to the parent species in viability and fecundity, and that assortative mating of the two parent species occurs in a mixed population. Hybridization may perhaps be maintained because selection favours the individual that will mate with its own species whenever it can tind one, but is capable of mating with other species when it cannot. In these conditions, hybridization is not a waste of reproductive energy.
Certain morphological changes occur in the vicinity of the hybrid zone. Far from the zone, caesareana resembles hierosolyma in shell-height, shell shape and genitalia; approaching the hybrid zone it diverges from hierosolyma in these characteristics and develops a distinct variant, caesareana var. werneri . This divergence may represent an accumulation of isolating mechanisms in the proximity of the hybrid zone, and thus be a case of reproductive character displacement. If indeed it is, then it differs from most described cases of character displacement in that the species are parapatric, not sympatric, and the displaced character is found not only at the common frontier but also from 2–12 km into the allopatric zone.     

厄瓜多尔西部新热带蛙(两栖纲: 无尾目:细趾蟾科)的分布特征及生态习性

Leptodactylus labrosus属于陆地坐-等型的捕食者,其食物包括地表的、掘地的及飞行昆虫,其中蚂蚁数量最多。曾有报道Bothrops asper是其天敌。L.labrosus主要栖息于落叶及半落叶林潮湿的环境中,偶尔也栖息于常绿林中。L.labrosus分布于厄瓜多尔西海岸的北部、中部、南部;秘鲁西海岸的北部、中部,分布地海拔可达600 m;及位于南厄瓜多尔和北秘鲁海拔高达1 300 m的干燥的安第斯山谷。其分布地区包括了厄瓜多尔和秘鲁海岸的潮湿的、季节性干燥的森林。在安第斯山脉斜坡的潮湿地带,L.labrosus与其他3种细趾蟾科的分布区重叠,但表现为生境分离。其分布特征与其他几种活动区域受限的两栖动物相似。Tumbesian地区应被认为是地方特有两栖动物的分布区。Choco和Tumbesian的中间区域是L.labrosus与其他细趾蟾科的生境分布重叠区,其生态及气候特征使其形成了独特的动物区系,包括几种地方特有物种。因此该地区应被划为西厄瓜多尔地方种区域。     

Systematics and distribution of the land snail Pene (Pulmonata: Enidae) in Israel

Formerly considered a subgenus of Buliminus, Pene is here, for reasons given, considered as a separate genus. Four species ( syriacus, sidoniensis, galilaea and auriculata ) inhabit Israel. A new subspecies, syriacus ramimensis , is described from north-east Galilee.
Northwards, towards the borderline with s. syriacus , the ratio mouth height/mouth diameter of s. ramimensis becomes first gradually larger, then reverses abruptly. The northernmost s. ramimensis sample is in a peculiar intermediate position suggesting that it represents a syriacus-ramimensis hybrid population which has reached stabilization.
Distribution borders are usually correlated with rain or substratum. The sidoniensis/galilaea borderline is unusual in that it crosses an area of nearly uniform climate, substratum and vegetation. Along it sidoneinsis and galilaea are found within centimetres of each other, suggesting that the borderline is here determined by interspecific competition rather than by physical factors.     

Mapping and analysis of distribution patterns of lichens on rural medieval churches in north-eastern Germany

Abstract:Lichen communities were examined on 62 churches in Mecklenburg-Vorpommern, Germany. Ninety-six lichen species and subspecies, and three species of lichenicolous fungi were identified. Tylothallia biformigera and Lecanora campestris subsp. dolomitica are reported as new to Germany, and another 20 species are considered as threatened. This implies that the stone walls of churches represent an extremely important habitat in Mecklenburg-Vorpommern, where natural rock outcrops are rare. The distribution of lichen species was analyzed quantitatively in relation to several habitat factors. Aspect, substratum and inclination were found to be important factors for 35, 34 and 31 species, respectively. The height of the relevé was a significant factor for many species. Twenty-three species, which are described in the literature with oceanic to suboceanic distributions, occur significantly more frequently near the coast. The ways in which microclimate affects each of these habitat factors and contributes to the presence or absence of a species or group of species are discussed. Some species have narrow and specific habitat demands, whereas others thrive under a wide range of environmental conditions. The advantages of a strictly schematic approach with a detailed statistical analysis are discussed.     

中国针茅属植物的地理分布

本文论述了中国针茅属植物的地理分布、生态特点及其与植被分布的关系。中国针茅属有32种1亚种及4变种,据该属各个种所处环境中的气候和土壤等因素的变化,不同种的分布也各异。属的分布区的类型属于吴征镒(1979)的中国植物区系分区的泛北极植物区中的6个植物亚区,即亚洲荒漠植物亚区,欧、亚森林植物亚区,青藏高原植物亚区,中国-喜马拉雅植物亚区,欧、亚草原植物亚区及中国-日本森林植物亚区。     

A key to the species of Mugilidae (Pisces) in the Northeastern Atlantic and Mediterranean, with explanatory notes

A key is given for identifying the eight species of Mugilidae of the Northeast Atlantic and Mediterranean. The use of Risso's names for four species is justified and explained and recognition is given to Tortonese's discovery that Mugil capurrii (Perugia) is a senior synonym of M. monodi Chabanaud. The relationship of Liza saliens to certain species of West and southern Africa is held to be additional support for the recognition of Protomugil Popov as a subgenus of Liza including these species. Chelon Röse, with type-species Mugil chelo Cuvier (= Chelon labrosus (Risso)), is recognized, following Jordan & Evermann (1917) and Schultz (1946), but its limits are differently conceived so as to include Crenimugil Schultz rather than Liza Jordan & Swain. The latter is held to comprise about 30 Old World species. The status of Chelon bispinosus (Bowdich) is discussed, with its bearing on possible population-differences in C. labrosus and the relationship of this species with C. crenilabis. The identity of Liza seheli (Forskål) is discussed and reasons are given for disagreeing with Wimpenny and others in applying this name to the species found at both ends of the Suez Canal zone. The latter is L. carinata (Ehrenberg in Cuvier & Valenciennes). Myxus maroccensis Mohr is believed to be a young Liza ramada.     

Investigation of Shell Characteristics in <Emphasis Type="Italic">Chondrula tridents</Emphasis> (Pulmonata,Enidae) from Highland and Plain Habitats of the Forest–Steppe of the Volga River Basin

Variability of the shell size characteristics was studied in the terrestrial mollusk Chondrula tridens (Müller, 1774) from highland and plain habitats in the forest–steppe of the Volga River basin. The shell height (SH) and width (SW), the height and width of the mouth, and the SH/SW ratio mostly contribute to the species variability. The SH/SW ratio reflects the species–specific constitution of the shell. Analysis of the elementary features and proportions, as well as of the mouth armament of shell structures, indicates significant heterogeneity of the species. The presence of scarps and rock outcrops in some regions studied explain large sizes of snail shells. The decrease in SH, increase in the roundness of shells, and better development of the mouth teeth in mollusks inhabiting the chalk steppe of the southern forest–steppe reflect their adaptation to more xerothermic conditions.     

Cultural monuments and nature conservation: a review of the role of kurgans in the conservation and restoration of steppe vegetation

Steppe is among the most endangered biomes of the world, especially in Eastern Europe, where more than 90 % of original steppes have been destroyed due to conversion into croplands, afforestation and other human activities. Currently, steppe vegetation is often restricted to places unsuitable for ploughing, such as ancient burial mounds called kurgans. The aim of our study was to collect and synthesise existing knowledge on kurgans by a review of research papers and grey literature. The proportion of kurgans covered by steppe vegetation increases from west to east and from lowlands to uplands. Despite their small size, kurgans act as biodiversity hotspots and harbour many red-listed species. High overall species richness and a high proportion of grassland specialists are maintained by a pronounced fine-scale environmental heterogeneity. The main factors threatening the biodiversity of kurgans are intensified agriculture and construction works. We conclude that kurgans can play a crucial role in preserving steppe vegetation, especially in intensively used agricultural landscapes in the western part of the steppe zone. Despite the vital role of kurgans in sustaining steppe vegetation, we identified serious knowledge gaps on their distribution, vegetation, flora and fauna and their potential role in steppe restoration.     

The Ecogeographical Distribution of Hippophae rhamnoides Subsp. sinensis and Its Phytogeographical Significance

Hippophae rhamnoides L. subsp. sinensis Rousi is confined to China. The subspecies, a primitive member of the genus, is one of important plant resources for food and medicinal industry and also a genetic resource for breeding. The subspecies ranges from Southwest to Northeast China, i .e .from the northeast part of Tibet to the sourthwest corner of the Da Hinggan Mountains ,through Loess Plateau. Made in this paper was an analysis of the limits of tolerance, the limiting factors and the fittest value, and of ecological factors regulating the distribution area of the subspecies such as heat, sunshine and rainfall. The analysis is based on comparison of the similarities between the distribution range and the isolines of the various ecological factors, combined with the field work of the subspecies. The result indicates that not only does the bush of Hippophae rhamnoides L. subsp. sinensis Rousi occupy a stable geographical range, but also it shows a zonal distribution pattern, controlled by rainfall and heat. Its geographical range is roughly located in the transitional zone of three vegetation regions in China, i.e. the east moist forest region, the northwest desert and steppe region and the Qinghai-Xizang Plateau alpine vegetation region. Therefore, the bush can be used for delimitating the three vegetation regions. This fact implies that the concept should be revised that the distribution of bushes is not of obvious horizontal-zonal pattern. Also discussed in the present paper are ecological conditions for the artificial Seabuckthron’s garden, the relationship between thegeographical range and the planting system in agriculture as well as the afforestation.     

Phytogeographical evidence for post‐glacial dispersal limitation of European beech forest species

The post‐glacial migration of European beech Fagus sylvatica has been addressed by many studies using either genetic or fossil data or a combination of both. In contrast to this, only little is known about the migration history of beech forest understorey species. In a review of phytosociological literature, we identified 110 plant species which are closely associated with beech forest. We divided the distribution range of European beech forests into 40 geographical regions, and the presence or absence of each species was recorded for each region. We compared overall species numbers per region and numbers of narrow‐range species (species present in <10 regions). A multiple regression model was used to test for the explanatory value of three potential diversity controls: range in elevation, soil type diversity, and distance to the nearest potential refuge area. A hierarchical cluster analysis of the narrow‐range species was performed. The frequency of range sizes shows a U‐shaped distribution, with 42 species occurring in <10 regions. The highest number of beech forest species is found in the southern Alps and adjacent regions, and species numbers decrease with increasing distance from these regions. With only narrow‐range species taken into consideration, secondary maxima are found in Spain, the southern Apennines, the Carpathians, and Greece. Distance to the nearest potential refuge area is the strongest predictor of beech forest species richness, while altitudinal range and soil type diversity had little or no predictive value. The clusters of narrow‐range species are in good concordance with the glacial refuge areas of beech and other temperate tree species as estimated in recent studies. These findings support the hypothesis that the distribution of many beech forest species is limited by post‐glacial dispersal rather than by their environmental requirements.     

The Role of Geographical and Ecological Factors on Population Divergence of the Neotropical otter <Emphasis Type="Italic">Lontra longicaudis</Emphasis> (Carnivora,Mustelidae)

The geographic distribution of the populations of a species are influenced by the spatial structure of the ecosystems, the environmental factors and the presence of geographic barriers. The Neotropical otter, Lontra longicaudis, is widely distributed throughout the Americas, where a wide range of environmental conditions and geographical features could promote genetic and morphological variation on the three currently recognized subspecies. In this study, we combined phylogeographic, morphometric and environmental niche modelling analyses to examine whether: (1) genetic variation is associated with the presence of barriers to gene flow and/or hydrography; (2) genetic and morphologic variation are associated with environmental variation; and (3) the observed variation in L. longicaudis populations corresponds to the previously defined subspecies. We found strong phylogeographic structure between the northern (L. l. annectens) and the two-southern subspecies (L. l. longicaudis and L. l. enudris), and although shallower, we also detected genetic differentiation between the two South American subspecies. Such genetic differentiation corresponds to the hydrography and to the geographical barriers characteristic of the distributional area of the species. We found a correlation between the shape of the skull and mandible with the environmental variation through the distribution of the species, and we rejected the hypothesis of niche equivalency and similarity between the three identified genetic lineages, suggesting adaptations to different environmental conditions. Our results support that the variation in environmental conditions, in concert with geographical barriers to gene flow and hydrography, have led to population divergence of L. longicaudis along the Neotropics. These results have important taxonomic implications for the species and its conservation.     

Phylogeography of the yucca moth Tegeticula maculata: the role of historical biogeography in reconciling high genetic structure with limited speciation

Tegeticula maculata is one of the most ancient and morphologically variable lineages within the yucca moths, yet has apparently undergone little diversification in comparison with much younger yucca moth lineages that have rapidly diversified. A phylogeographic approach was used to determine the number of independent lineages within T. maculata and to examine whether these patterns corresponded with morphological differences between its subspecies maculata and extranea. Phylogenetic analysis of mitochondrial DNA sequence variation indicated that the two subspecies are in separate clades, but there was also an equally deep split within subspecies maculata. There was no evidence for gene flow among regions and there was considerable substructure within clades. The phylogeographic structure of moth populations among and within subspecies can be explained in part by historical biogeographic boundaries and increasingly patchy postglacial distribution of the exclusive host plant, Hesperoyucca whipplei. Local specialization and co-adaptation would be possible in the absence of apparent gene flow, yet gross morphological divergence is limited to the very old split between the subspecies. Sorting of ancient mitochondrial lineages followed by local genetic differentiation may explain the pattern of high genetic structure with limited speciation.     

Distribution Patterns of Slender Loris Subspecies (<Emphasis Type="Italic">Loris lydekkerianus</Emphasis>) in Kerala,Southern India

Gray slender lorises (Loris lydekkerianus) are 1 of 2 nocturnal primate genera occurring in India. Although the distribution and abundance of the species is known for some parts of southern India, the relative distribution of the 2 subspecies, Loris lydekkerianus lydekkerianus and L. l. malabaricus, and their comparative densities and extent of overlap between their distributions remains largely unknown. We investigated the distribution pattern and relative density of slender lorises in the Western Ghats mountain range in the state of Kerala in southern India. We surveyed 36 forest ranges in 17 forest divisions of northern and central Kerala from February to November 2009 for the presence of lorises. We sighted slender lorises in 22 forest ranges in a variety of vegetation types, and the relative abundance of the species ranged from 0.02 to 1.44 lorises/km. Our results confirm that both loris subspecies are present in Kerala: Mysore slender lorises have a narrow patchy distribution on the eastern edges of the Western Ghats mountain range, and Malabar slender lorises have a fairly contiguous distribution on the western slopes of the Western Ghats. We recommend more detailed surveys in southern Kerala to identify the distribution patterns of the subspecies in these areas.     

Multilocus approach reveals an incipient differentiation process in the Stone-curlew, <Emphasis Type="Italic">Burhinus oedicnemus</Emphasis> around the Mediterranean basin

The Stone-curlew Burhinus oedicnemus, a steppe bird species, is mainly distributed in the Mediterranean and Macaronesian regions, which are considered hotspots of biodiversity with priority for animal and plant species richness conservation. In this study, we investigated the genetic diversity of the Stone-curlew in the Mediterranean basin and in the Canary Islands by applying a multilocus approach. We analysed mitochondrial and nuclear markers in order to evaluate the genetic structure and the congruence between morphological subspecies and geographic samples. We found a significant level of genetic differentiation between Mediterranean and Canary Island populations with all markers. Both in the Mediterranean basin and in the Canary Islands, we found a significant level of genetic diversity with nuclear markers only. We identified seven population groups, including insular populations. The four subspecies described for the Western Palaearctic were confirmed with some changes in distribution range. In spite of habitat fragmentation and negative population trend, the Stone-curlew showed a significant level of genetic diversity and gene flow among continental populations. However, islands constitute important reservoirs of genetic diversity and a potential for the evolution of the species.     

Morphological and genetic differentiation of Eremina desertorum (Gastropoda,Pulmonata, Helicidae) in Egypt

To understand the processes that result in morphological and genetic diversity, we studied the differentiation of the land snails Eremina d. desertorum and Eremina desertorum irregularis in the deserts of northern Egypt. These two taxa are differentiated with regard to shell size and shape and are separated by a narrow hybrid zone west of Alexandria. The lack of differences in the genitalia and the lack of reciprocal monophyly of the mitochondrial haplotypes of E. d. desertorum and E. desertorum irregularis support their classification as subspecies rather than distinct species. Low genetic distances indicate that the differentiation is probably less than half a million years old. The genetic data indicate a population expansion in agreement with other evidence that the Nile region in northern Egypt was more humid well into historical times than today. Shell size and shape are correlated with a climatic gradient from cooler and more humid conditions along the Mediterranean coast to arid and hot conditions in the interior. The decrease of body size with decreasing precipitation and increasing temperature might be explained by limited time for food intake in the more arid regions. The shape differences between the taxa are partly an indirect consequence of selection for body size, but are also directly affected by selection for reduction of aperture size.     

Spatiotemporal variance of environmental conditions in Australian artesian springs affects the distribution and abundance of six endemic snail species

Artesian springs in arid Australia house endemic species with very small geographic distributions (most <50 km²). These species have limited dispersal capabilities, but little is known about environmental variance within and across these springs and how it, too, may limit their distribution and abundance. At the Pelican Creek springs complex, the full diversity of endemic gastropod fauna is found only in springs with deep pools, an area thought to provide greater environmental stability. This implies that the distributions of most snail species at this site may be restricted by their narrow environmental requirements and limits. This study monitored spatiotemporal environmental variance in a subset of the Pelican Creek springs (within Edgbaston Reserve) across one year to assess whether pool areas differ from tail areas, and how patterns of abundance of six snail species from three different families correspond to this variance. Springs fluctuated considerably in size, depth, water chemistry and temperature at daily and seasonal scales. Patterns of environmental variance differed across areas; pools were spatiotemporally stable, and tails were ephemeral and environmentally variable. The snail species occupied these areas in different ways. Species restricted to deep springs generally had significantly higher abundance in pool areas, and most had narrow environmental limits. In contrast, species found in a greater number of springs, including those with no pool, occupied pool and tail areas and generally had broader environmental limits. Environmental variance within and across springs affects the distribution of snails in a species-specific fashion. This has important implications for how we study springs and reveals that whilst the vast majority of species are restricted to areas of environmental stability, some can persist in the most environmentally variable areas.     

Environmental harshness,latitude and incipient speciation

Are rates of evolution and speciation fastest where diversity is greatest – the tropics? A commonly accepted theory links the latitudinal diversity gradient to a speciation pump model whereby the tropics produce species at a faster rate than extra‐tropical regions. In this issue of Molecular Ecology, Botero et al. ( 2014 ) test the speciation pump model using subspecies richness patterns for more than 9000 species of birds and mammals as a proxy for incipient speciation opportunity. Rather than using latitudinal centroids, the authors investigate the role of various environmental correlates of latitude as drivers of subspecies richness. Their key finding points to environmental harshness as a positive predictor of subspecies richness. The authors link high subspecies richness in environmental harsh areas to increased opportunities for geographic range fragmentation and/or faster rates of trait evolution as drivers of incipient speciation. Because environmental harshness generally increases with latitude, these results suggest that opportunity for incipient speciation is lowest where species richness is highest. The authors interpret this finding as incompatible with the view of the tropics as a cradle of diversity. Their results are consistent with a growing body of evidence that reproductive isolation and speciation occur fastest at high latitudes.     

中国戈壁针茅草原的分布、群落特征和分类

戈壁针茅(Stipa tianschanica var. gobica)草原主要分布于荒漠草原区的石质丘陵或石质山坡, 向东可以分布在典型草原区的石质丘陵或山地, 向西也可以分布在荒漠区的石质山坡上。该研究调查了中国戈壁针茅草原的主要植被类型, 通过对115个样地的样方数据分析, 量化描述了这一草原类型的主要植物群落特征。结果表明, 中国戈壁针茅草原共有维管植物272种, 隶属于38科127属; 其中裸子植物3种, 隶属于1科1属; 被子植物269种, 隶属于37科126属, 物种数大于等于10种的科为: 菊科、禾本科、豆科、蔷薇科、百合科、藜科、石竹科; 戈壁针茅草原植物区系的生活型谱以地面芽植物为主, 共178种植物, 占总种数的65.44%; 水分生态类型以旱生植物为主, 共120种, 占总种数的44.12%; 植物区系地理成分上以东古北极分布种和亚洲中部分布种(含其变型)最多, 分别为82种和80种, 占总种数的30.14%和29.41%; 盖度等级划分上以0.1%-1.0%的盖度最多, 共174种, 占总种数的63.97%; 恒有度等级划分上以I级(0-20%)的物种数最多, 共258种植物, 占所有植物种数的94.85%。基于群落调查数据, 按照群落-外貌分类原则, 将戈壁针茅群系划分为8个群丛组106个群丛。     

Distribution,community characteristics and classification of Stipa tianschanica var. gobica steppe in China

戈壁针茅(Stipa tianschanica var. gobica)草原主要分布于荒漠草原区的石质丘陵或石质山坡, 向东可以分布在典型草原区的石质丘陵或山地, 向西也可以分布在荒漠区的石质山坡上。该研究调查了中国戈壁针茅草原的主要植被类型, 通过对115个样地的样方数据分析, 量化描述了这一草原类型的主要植物群落特征。结果表明, 中国戈壁针茅草原共有维管植物272种, 隶属于38科127属; 其中裸子植物3种, 隶属于1科1属; 被子植物269种, 隶属于37科126属, 物种数大于等于10种的科为: 菊科、禾本科、豆科、蔷薇科、百合科、藜科、石竹科; 戈壁针茅草原植物区系的生活型谱以地面芽植物为主, 共178种植物, 占总种数的65.44%; 水分生态类型以旱生植物为主, 共120种, 占总种数的44.12%; 植物区系地理成分上以东古北极分布种和亚洲中部分布种(含其变型)最多, 分别为82种和80种, 占总种数的30.14%和29.41%; 盖度等级划分上以0.1%-1.0%的盖度最多, 共174种, 占总种数的63.97%; 恒有度等级划分上以I级(0-20%)的物种数最多, 共258种植物, 占所有植物种数的94.85%。基于群落调查数据, 按照群落-外貌分类原则, 将戈壁针茅群系划分为8个群丛组106个群丛。