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One Species (one + species)
Kinds of One Species Selected AbstractsA New Record of Pterotocera ussurica Djakonov (Lepidoptera, Geometridae) from KoreaENTOMOLOGICAL RESEARCH, Issue 2 2003Yoo-Hang SHIN ABSTRACT One species of the genus Pterotocera Staudinger, P. ussurica Djakonov, is first recorded from Korea. Description of adult and illustration of male genitalia are provided. Based on the previous and the present works, there are 22 winter geometrid moths in Korea. [source] Some new and interesting Astragalus species (Fabaceae) from TurkeyFEDDES REPERTORIUM, Issue 1-2 2008D. Podlech Prof. Dr. During the work on a revision of the Old World Astragali, 14 new species could be found among the unnamed material of several herbaria. Furthermore two new sections had to be described. They are presented here. Sect. Hololeuce: A. nigropedunculatus,A. suserianus; Sect. Incani: A. darendensis; Sect. Malacothrix: A. adiyamanensis, A. aladagensis, A. calvertii; Sect. Onobrychoidei: A. helbaekii, A. pseudovegetus, A. rausianus, A. sakaryaensis, A. tunceliensis; Sect. Ornithopodium: A. horasanicus; Sect. Stereothrix: A. mahmutlarensis; Sect. Synochreati: A. mugliensis; Sect. Davisiana, sect. nova; Sect. Woronowia, sect. nova. One species had to be renamed: A. blandulus and three new records for the flora of Turkey are indicated: A. apricus (sect. Caprini), A. dzhebrailicus (sect. Hololeuce) and A. expetitus (sect. Hymenostegis). (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Einige neue und interessante Astragalus -Arten (Fabaceae) aus der Türkei Während der Arbeit an einer Revision der altweltlichen Astragalus -Arten konnten in bisher unbestimmtem Material verschiedener Herbarien 14 neue Arten gefunden werden. Auch zwei Sektionen der Gattung mussten neu aufgestellt werden. Sie werden hier beschrieben. Sect. Hololeuce: A. nigropedunculatus,A. suserianus; Sect. Incani: A. darendensis; Sect. Malacothrix: A. adiyamanensis, A. aladagensis, A. calvertii; Sect. Onobrychoidei: A. helbaekii, A. pseudovegetus, A. rausianus, A. sakaryaensis, A. tunceliensis; Sect. Ornithopodium: A. horasanicus; Sect. Stereothrix: A. mahmutlarensis; Sect. Synochreati: A. mugliensis; Sect. Davisiana, sect. nova; Sect. Woronowia, sect. nova. Eine Art musste umbenannt werden: A. blandulus. Drei Arten konnten für die Türkei neu nachgewiesen werden: A. apricus (Sect. Caprini), A. dzhebrailicus (Sect. Hololeuce) und A. expetitus (Sect. Hymenostegis). [source] The distribution of the gondwanine ostracod Rostrocytheridea Dingle: palaeozoogeographical implicationsGEOLOGICAL JOURNAL, Issue 2 2007Sara C. Ballent Abstract The genus Rostrocytheridea is strictly gondwanine in its distribution and, in Argentina, is shown to be restricted to Patagonia. Of the six recorded Argentinian species, five are restricted to the southern part of South America: Rostrocytheridea opisthorhynchus nov. sp. (late Tithonian-Berriasian), Rostrocytheridea sp. (Valanginian), Rostrocytheridea cerasmoderma nov. sp., Rostrocytheridea covuncoensis Musacchio (Hauterivian) and Rostrocytheridea? sp. (Campanian). One species, Rostrocytheridea ornata Brenner and Oertli, is of much wider distribution, occurring in the Neocomian of South Africa and the Hauterivian of central-west Argentina. In Australia, the genus first appears in the Albian-Cenomanian and ranges up to the Santonian with two species: Rostrocytheridea canaliculata Bate and Rostrocytheridea westraliensis (Chapman). The youngest record of the genus is R. hamiltonensis Fauth and Seeling from the Middle to Upper Campanian of the James Ross Basin, Antarctic Peninsula. The implications for intercontinental correlation and the reconstruction of palaeo-migration routes are considered. Copyright © 2007 John Wiley & Sons, Ltd. [source] Partitioning the effects of biodiversity and environmental heterogeneity for productivity and mortality in a tropical tree plantationJOURNAL OF ECOLOGY, Issue 5 2008Chrystal Healy Summary 1Over 5000 trees were grown in plots of differing diversity levels (1, 3 and 6 species) in a plantation established in Panama. Four and five years after establishment, we analysed parameters related to the productivity of this tropical plantation (tree survival, height and biomass as well as plot basal area) to test for the presence of biodiversity effects. The relative importance of environmental heterogeneity (such as soil, topography, and drainage) and biodiversity on tree growth and mortality was determined using partial redundancy analysis. 2Hierarchical clustering revealed nine different soil clusters based on soil quality and drainage. By chance, the six-species plots were apparently established on more variable soils then on the other diversity levels. We found little evidence for spatial autocorrelation between subplots, with the exception of four subplots located on a ridge that extends on the North,South axis of the plantation and corresponds to a zone of higher productivity. 3The redundancy analysis indicated that environmental heterogeneity and biodiversity together explained around 50% of the variation in subplot productivity and tree mortality. Environment explained 35,57% of the variation in productivity and mortality, respectively, whereas diversity explained an additional 23,30%. 4Our simulation model revealed a significant positive effect of biodiversity on growth but no effect of biodiversity on mortality. The standardized effect sizes that we used to detect over- or under-yielding or no effect in comparison with monoculture were highly variable and the variability was largely explained by traits related to site topography. 5Synthesis. In our tropical tree plantation, we detected biodiversity effects at a scale relevant to conservation and quantified the relative importance of environmental heterogeneity and diversity on tree growth and mortality. Our results support the idea that environmental factors could act as hidden sources of variability in biodiversity experiments. Environmental and spatial heterogeneity induced variable responses to biodiversity and amplified the differences between three- and six-species plots. Species identity explained more variation in productivity than did the species diversity. One species, Cedrela odorata, was associated with increased productivity. [source] Epigean and subterranean ichthyofauna from the São Domingos karst area, Upper Tocantins River basin, Central BrazilJOURNAL OF FISH BIOLOGY, Issue 5 2003M. E. Bichuette In a survey of epigean and cave streams in the São Domingos karst area, 38 species were present in the stream reaches, including 10 characiforms, 19 siluriforms, seven gymnotiforms and two perciforms. One species of Astyanax and the new armoured catfish species Parotocinclus were the most common epigean fishes in São Domingos. The most conspicuous non-troglomorphic cave fishes were Hoplerythrinus unitaeniatus, Astyanax sp., Brycon sp. and two species of Imparfinis, with I. hollandi being the most common fish in most caves. São Domingos karst area has the most diverse and abundant Brazilian cavefish fauna, not only in terms of troglobitic species but also in general fish richness, with 22 non-troglomorphic species recorded in caves in addition to five troglobitic ones. Most fishes examined for stomach contents had at least partially full stomachs. The studied fishes were carnivorous, feeding primarily on aquatic insects. Fishes with developed gonads recorded in caves were I. hollandi, Rhamdia quelen, Pseudocetopsis plumbeus, Hoplerythrinus unitaeniatus and Cichlasoma araguaiensis, indicating a potential for reproduction in the subterranean habitat. [source] TAXONOMIC STUDY OF TWO NEW GENERA OF FUSIFORM GREEN FLAGELLATES, TABRIS GEN.JOURNAL OF PHYCOLOGY, Issue 2 2009On the basis of LM, we isolated strains of two species of fusiform green flagellates that could be assigned to former Chlorogonium (Cg.) Ehrenb. One species, "Cg."heimii Bourr., lacked a pyrenoid in its vegetative cells and required organic compounds for growth. The other was similar to Cg. elongatum (P. A. Dang.) Francé and "Cg."acus Nayal, but with slightly smaller vegetative cells. Their molecular phylogeny was also studied based on combined 18S rRNA, RUBISCO LSU (rbcL), and P700 chl a -apoprotein A2 (psaB) gene sequences. Both species were separated from Chlorogonium emend., Gungnir Nakada and Rusalka Nakada, which were formerly assigned to Chlorogonium. They were accordingly assigned to new genera, Tabris Nakada gen. nov. and Hamakko (Hk.) Nakada gen. nov. as T. heimii (Bourr.) Nakada comb. nov. and Hk. caudatus Nakada sp. nov., respectively. Tabris is differentiated from other genera of fusiform green flagellates by its vegetative cells, which only have two apical contractile vacuoles and lack a pyrenoid in the chloroplast. Hamakko, on the other hand, is distinguishable by the fact that its pyrenoids in vegetative cells are penetrated by flattened thylakoid lamellae. [source] A new case of intralacustrine radiation in Amphipoda.JOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 2 2009A new genus, Amphipoda) from the ancient lake Fuxian Hu in Yunnan, China, three new species of Anisogammaridae (Crustacea Abstract Fuxian Hu is a deep freshwater lake in the high plateau in Yunnan Province, China. After a study and description of Fuxiana yangi Sket, 2000 from deep waters, some coastal samples of amphipods were taxonomically evaluated. Four species were recognized, which in winter co-occur along most of the shallow littoral zone around the lake; they were identified as members of the family Anisogammaridae. One species was recognized as a slightly differentiated Eurypodogammarus helobius Hou et al., 2005, and the others as new species of Fuxigammarus gen. n. Results of a cladistic analysis performed on morphological characters from published descriptions, which included all lacustrine taxa and representatives of all other anisogammarid genera, established the monophyly of the new genus. Endemic character and monophyly of the group testify to an intralacustrine radiation within Fuxigammarus. Fuxian Hu is the fifth known lake in the world to contain a radiation of amphipods and is the only one inhabited by members of Anisogammaridae. Fuxigammarus gen. n. is characterized by a small and slender body, scant dorsal setosity-spinosity, and single, sausage-shaped accessory lobes on coxal gills, antennae without calceoli and rod shaped uropod III. These species differ substantially from each other by characters that do not occur in other anisogammarid genera. The type species F. antespinosus sp. nov. has spiniform dorsal setae shifted forward. Fuxigammarus barbatus sp. nov. has extremely setose antennal bases and mandibular palps and an elongated proximal flagellar article of antenna II. Fuxigammarus cornutus sp. nov. has a pair of dorsal spiniform setae only on humped urosomite I and the usually spiniform setae replaced by flexible setae on the telson. These characters are a kind of counterpart to the specific body armature of the Bajkal amphipods. Zusammenfassung Fuxian Hu ist ein tiefer Süßwassersee auf dem Hochplateau der Yunnan-Provinz in China. Nach der Beschreibung von Fuxiana yangi Sket, 2000 aus den Tiefen des Sees wurden auch Amphipoden-Proben aus dem Litoralbereich taxonomisch ausgewertet. Vier Arten wurden erkannt, die im Winter gemeinsam das flache Litoral rund um den See bewohnen. Sie wurden der Familie Anisogammaridae zugeordnet. Eine der Arten konnte als leicht differenzierte Eurypodogammarus helobius Hou et al., 2005 bestimmt werden, während die anderen als neue Arten einer neuen Gattung, Fuxigammarus gen.nov., beschrieben werden. Die Monophylie der neuen Gattung wurde durch eine phylogenetische Analyse bestätigt, die alle im See bekannten Arten sowie Vertreter aller anderen Anisogammariden-Gattungen mit einbezog. Der Endemismus und die Monophylie der Gattung deuten auf eine intralakustrische Radiation von Fuxigammarus. Somit ist Fuxian Hu der fünfte See weltweit, in dem eine Radiation von Amphipoden nachgewiesen wurde, und der einzige davon mit Anisogammariden. Fuxigammarus gen. n. besitzt einen kleinen und schlanken Körper, eine arme Dorsalbestachelung, nur je eine Nebenast auf jeder Coxalkieme, Antennen ohne Calceoli und stabförmige Uropoden III. Sie unterscheiden sich deutlich in Merkmalen, die bei anderen Anisogammariden nicht vorkommen. Die Typusart F. antespinosus sp. nov. besitzt nach vorne verdrängte Dorsal-Stacheln. Fuxigammarus barbatus sp. nov. hat dicht setose Antennenenbasen und Mandibularpalpen sowie ein verlängertes proximales Glied im Flagellum der Antenne II. Fuxigammarus cornutus sp. nov. besitzt nur ein Paar stachelförmige Dorsal-Setae auf dem gewölbtem Urosomit I, und weiche anstatt der sonst normalen stachelförmigen Setae auf dem Telson. Diese Merkmale wirken wie ein Gegenstück zu den spezifischen Schutzstrukturen der Baikal-Amphipoden. [source] Leaf respiratory CO2 is 13C-enriched relative to leaf organic components in five species of C3 plantsNEW PHYTOLOGIST, Issue 3 2004Cheng-yuan Xu Summary ,,Here, we compared the carbon isotope ratios of leaf respiratory CO2 (,13CR) and leaf organic components (soluble sugar, water soluble fraction, starch, protein and bulk organic matter) in five C3 plants grown in a glasshouse and inside Biosphere 2. One species, Populus deltoides, was grown under three different CO2 concentrations. ,,The Keeling plot approach was applied to the leaf scale to measure leaf ,13CR and these results were compared with the ,13C of leaf organic components. ,,In all cases, leaf respiratory CO2 was more 13C-enriched than leaf organic components. The amount of 13C enrichment displayed a significant species-specific pattern, but the effect of CO2 treatment was not significant on P. deltoides. ,,In C3 plant leaves, 13C-enriched respiratory CO2 appears widespread. Among currently hypothesized mechanisms contributing to this phenomenon, non-statistical carbon isotope distribution within the sugar substrates seems most likely. However, caution should be taken when attempting to predict the ,13C of leaf respiratory CO2 at the ecosystem scale by upscaling the relationship between leaf ,13CR and ,13C of leaf organic components. [source] Systematics of Chaetocerotaceae (Bacillariophyceae).PHYCOLOGICAL RESEARCH, Issue 2 2003SUMMARY In order to construct a model of evolutionary relationships within the diatom family Chaetocerotaceae, 37 species of Chaetoceros Ehrenberg, representing all subgenera and 21 of 22 subgeneric sections of the genus, plus three Bacteriastrum Shadbolt species, representing both of its subgeneric sections, were subjected to cladistic analysis. One species each of Eucampia Ehrenberg, Cerataulina Peragallo, Hemiau-lus Ehrenberg, Attheya West and Gonioceros H. & M. Peragallo were used as outgroups. A matrix of 65 binary and multistate morphological characters was constructed, with data being gathered from original observation of material in the light and electron microscopes, and from the published literature. The analysis yielded 36 most-parsimonious cladograms of 316 steps; incongruence between trees is largely restricted to some taxa representing undersampled sections of Chaetoceros subg. Hyalochaete. The robustness of this hypothesis was examined in several ways. To assess the effect of character weighting, the bootstrap was used to randomly weight characters. The parsimony criterion was relaxed via a decay index, and finally, the tree length was compared to that of trees randomly generated from the data matrix. The majority of investigated species of Chaetoceros subg. Phaeoceros, Chaetoceros subg. Hyalochaete and Bacteriastrum appear to belong to a continuous grade, rather than comprising individual clades. Chaetoceros is paraphyletic. Thus, the traditional classification does not accurately reflect the hypothesized phylogenetic relationships of this family. [source] Brain size and encephalization in early to Mid-Pleistocene HomoAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2004G. Philip Rightmire Abstract Important changes in the brain have occurred during the course of human evolution. Both absolute and relative size increases can be documented for species of Homo, culminating in the appearance of modern humans. One species that is particularly well-represented by fossil crania is Homo erectus. The mean capacity for 30 individuals is 973 cm3. Within this group there is substantial variation, but brain size increases slightly in specimens from later time periods. Other Middle Pleistocene crania differ from those of Homo erectus. Characters of the facial skeleton, vault, and cranial base suggest that fossils from sites such as Arago Cave in France, the Sima de los Huesos in Spain, Bodo in Ethiopia, Broken Hill in Zambia, and perhaps Dali in China belong to the taxon Homo heidelbergensis. Ten of these mid-Quaternary hominins have brains averaging 1,206 cm3 in volume, and many fall beyond the limits of size predicted for Homo erectus of equivalent age. When orbit height is used to construct an index of relative brain size, it is apparent that the (significant) increase in volume documented for the Middle Pleistocene individuals is not simply a consequence of larger body mass. Encephalization quotient values confirm this finding. These changes in absolute and relative brain size can be taken as further corroborative evidence for a speciation event, in which Homo erectus produced a daughter lineage. It is probable that Homo heidelbergensis originated in Africa or western Eurasia and then ranged widely across the Old World. Archaeological traces indicate that these populations differed in their technology and behavior from earlier hominins. Am J Phys Anthropol, 2003. © 2003 Wiley-Liss, Inc. [source] Long-Term Variation in Small Mammal Abundance in Forest and Savanna of Bolivian CerradoBIOTROPICA, Issue 4 2009Article first published online: 9 MAR 200, Louise H. Emmons ABSTRACT Small mammals were trapped annually in two savanna and two forest plots in cerrado habitats of Noel Kempff Mercado National Park, Santa Cruz, Bolivia, for 5,10 yr. Eighteen species were captured in forest and seven species in savanna. Species numbers and total number of individuals captured were tightly correlated. In forest, species and abundance varied interannually by up to fourfold in one plot and to 100-fold in the other, and showed alternating highs and lows as is typical for small mammals. The largest faunal differences were due not to site differences, but to year differences, with markedly different patterns in forests and savannas. Abundance was not correlated with rainfall overall, but showed correlation in exceptional years of rainfall and ENSO drought. In savanna, species and overall abundance declined without recovery during 3 yr after reaching minimum numbers in 2004. One species, Cavia aperea, became extinct on both plots, and subsequently, apparently on the entire savanna. Both herbivorous and insectivorous species declined together. Rainfall, fire, and flooding do not seem to account for savanna rodent declines. I propose the novel hypothesis that smoke from anthropogenic burning raises nocturnal temperatures and prevents dew formation, and that a decrease in nightly dry season dewfall has been instrumental in rodent declines. Anecdotal and climatic data are consistent with this hypothesis, but it cannot yet be tested. [source] Systematics of the Nasa poissoniana group (Loasaceae) from Andean South AmericaBOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 3 2009TILO HENNING The monophyletic Nasa poissoniana group (Loasaceae, subfamily Loasoideae) is revised on the basis of extensive field studies, observations in cultivation and the revision of herbarium specimens. A core of taxa has been considered as closely allied on the basis of morphology in the past, but several additional taxa have been recognized as allied to this group on the basis of molecular data. One species, N. raimondii, formerly placed in the N. stuebeliana group, is now transferred to the N. poissoniana complex as a result of the molecular findings. Nasa poissoniana ssp. glandulifera is described as new to science on the basis of morphologically divergent collections of N. poissoniana from two northern departments of Peru. Numerous new localities, often far from the previously known distribution area, are reported for several species. The N. poissoniana group has its centre of diversity in the inner Andean valleys of southern Peru, quite unlike all other groups of Nasa, with centres of diversity in the Amotape,Huancabamba Zone in northern Peru and southern Ecuador. Descriptions, drawings and a distribution map and key to all taxa are provided, and detailed information on habitat and distribution is given for each species. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 161, 278,301. [source] Multispecies and Multiscale Conservation Planning: Setting Quantitative Targets for Red-Listed Lichens on Ancient OaksCONSERVATION BIOLOGY, Issue 3 2010HEIDI PALTTO bosque de encino maduro; cantidad de hábitat; encino antiguo; escala espacial; líquenes en la lista roja Abstract:,Species occurrence in a habitat patch depends on local habitat and the amount of that habitat in the wider landscape. We used predictions from empirical landscape studies to set quantitative conservation criteria and targets in a multispecies and multiscale conservation planning effort. We used regression analyses to compare species richness and occurrence of five red-listed lichens on 50 ancient oaks (Quercus robur; 120,140 cm in diameter) with the density of ancient oaks in circles of varying radius from each individual oak. Species richness and the occurrence of three of the five species were best explained by increasing density of oaks within 0.5 km; one species was best explained by the density of oaks within 2 km, and another was best predicted by the density of oaks within 5 km. The minimum numbers of ancient oaks required for "successful conservation" was defined as the number of oaks required to obtain a predicted local occurrence of 50% for all species included or a predicted local occurrence of 80% for all species included. These numbers of oaks were calculated for two relevant landscape scales (1 km2 and 13 km2) that corresponded to various species responses, in such a way that calculations also accounted for local number of oaks. Ten and seven of the 50 ancient oaks surveyed were situated in landscapes that already fulfilled criteria for successful conservation when the 50% and 80% criteria, respectively, were used to define the level of successful conservation. For cost-efficient conservation, oak stands in the landscapes most suitable for successful conservation should be prioritized for conservation and management (e.g., grazing and planting of new oaks) at the expense of oak stands situated elsewhere. Resumen:,La ocurrencia de especies en un parche de hábitat depende del hábitat local y de la cantidad de ese hábitat en un paisaje más amplio. Utlizamos predicciones de estudios de paisaje empíricos para definir criterios y objetivos de conservación cuantitativos en un esfuerzo de planificación de la conservación para múltiples especies y escalas. Utilizamos análisis de regresión para comparar la riqueza y ocurrencia de especies de cinco líquenes en la lista roja sobre 20 encinos antiguos (Quercus robur; 120,140 cm de diámetro) con la densidad de encinos antiguos en círculos de radio variable desde cada encino individual. La riqueza y ocurrencia de tres de las cinco especies fue mejor explicada por el incremento de la densidad de encinos en 0.5 km; una especie fue mejor explicada por la densidad de encinos en 2 km, y la otra fue mejor pronosticada por la densidad de encinos en 5 km. Los números mínimos de encinos antiguos requeridos para una "conservación exitosa" fueron definidos como el número de encinos requeridos para obtener una ocurrencia local pronosticada de de 50% para todas las especies incluidas o una ocurrencia local pronosticada de 80% para todas las especies incluidas. Estos números de encinos fueron calculados para dos escalas de paisaje relevantes (1 km2 y 13 km2) que correspondieron a las respuestas de varias especies, de tal modo que los cálculos también incluyeron el número local de encinos. Diez y siete de los 50 encinos antiguos estaban situados en paisajes que ya cumplían criterios para conservación exitosa cuando los criterios de 50% y 80%, respectivamente, fueron usados para definir el nivel de conservación exitosa. Para una conservación redituable, los bosques de encinos en los paisajes más aptos para la conservación exitosa deberían ser priorizados para conservación y manejo (e. g., pastoreo y siembra de encinos nuevos) a costa de bosques de encino situados en otros lados. [source] The effect of short fire cycles on the cover and density of understorey sprouting species in South African mountain fynbosDIVERSITY AND DISTRIBUTIONS, Issue 5 2000J. H. J. Vlok Abstract. Two South African mountain fynbos sites were studied to determine the effect of short fire cycles on the cover and density of understorey sprouting species and their subsequent effect on plant-species richness. Frequent fires (4,6 years between burns) increased the cover of sprouting species by 32% when compared to an adjacent site where the penultimate fire was 28 years previously. There was little or no effect of fire frequency on the densities of understorey sprouters; however, individuals were larger at sites with short fire cycles. The response of individual species of sprouters was variable with one species, Hypodiscus striatus, showing no response to fire frequency. The impact of sprouting species on the species richness of the plant community was great. The mean number of species recorded in quadrats with a high cover of sprouters was 60% lower in comparison to quadrats with low covers or under the burned skeletons of overstorey proteas. The effect of sprouters was consistent for all functional groups of species (i.e. sprouters, non-sprouters, short-lived and long-lived species), in each case reducing the number of species present. [source] Ontogenetic scaling of scansorial surface area and setal dimensions of Chondrodactylus bibronii (Gekkota: Gekkonidae): testing predictions derived from cross-species comparisons of gekkotansACTA ZOOLOGICA, Issue 1 2009Nicole B. Webster Abstract Little is known of how the adhesive apparatus of gekkotans scales with growth. Cross-species comparisons of certain characteristics, using size as a comparator to investigate scaling relationships, suggest certain relationships between subdigital pad area and body size. The manner in which the adhesive apparatus grows and scales within any one species, however, remains unknown, and it is unclear whether interspecific and intraspecific patterns are similar. To address this, we examined a post-hatching ontogenetic series of the southern African gecko Chondrodactylus bibronii and demonstrate that setal density, setal basal diameter and setal spacing remain relatively constant in relation to size, indicating conserved subdigital pad assembly rules that are independent of size. Conversely, however, average and maximal setal lengths increase slightly and isometrically with size, an outcome that is probably explained by setal row recruitment, and the surface area of the subdigital pads scales close to, but below, isometry with respect to body mass and snout,vent length, it therefore does not increase sufficiently with size to compensate for the increase in mass. As a result, relative adhesive capacity decreases with growth with a regression slope of ,0.45. [source] Autopodial skeleton evolution in side-necked turtles (Pleurodira)ACTA ZOOLOGICA, Issue 3 2007Marcelo R. Sánchez-Villagra Abstract Carpal and tarsal anatomy was documented based on the observation of dry skeletons of adult specimens representing 25 species in 15 genera and on data taken from the literature. In addition, histological sections and cleared and double-stained autopodia of recently hatched and juvenile specimens representing seven chelid and pelomedusoid species were studied. There is much more morphological diversity in the manus than in the pes. Variation in autopodial skeletons includes: the astragalus and calcaneum are either separated or fused; fusion of distal carpals 3,4,5 or just 4,5; number of centralia in the carpus; and presence/absence of a pisiform and of an accessory radial element. The widespread and probably basal phalangeal formula for Pleurodira is 2.3.3.3.3. Deviations are Pelomedusa subrufa, exhibiting a reduction to 2.2.2.2.2, Pelusios spp. with one phalanx less in digit I and for one species in digit V as well, and Acanthochelys pallidipectoris with an additional phalanx in the fourth finger. Six discrete characters itemizing some of the morphological variation observed were plotted on a composite pleurodire phylogeny, revealing not only homoplastic patterns but also the utility of some characters in supporting the monophyly of several clades. The pisiform is the last carpal element to ossify in Chelus fimbriatus. We hypothesize that the so-called fifth hooked metatarsal represents the fusion of distal tarsal 5 with metatarsal V. The accessory radial element that was occasionally present in the turtles examined may represent an atavism of the otherwise lost radiale of turtles. [source] Spatial pattern of adult trees and the mammal-generated seed rain in the Iberian pearECOGRAPHY, Issue 3 2010Jose M. Fedriani The degree to which plant individuals are aggregated or dispersed co-determines how a species uses resources, how it is used as a resource, and how it reproduces. Quantifying such spatial patterns, however, presents several methodological issues that can be overcome by using spatial point pattern analyses (SPPA). We used SPPA to assess the distribution of P. bourgaeana adult trees and their seeds (within fecal samples) dispersed by three mammals (badger, fox, and wild boar) within a 72-ha plot across a range of spatial scales. Pyrus bourgaeana trees in our study plot (n=75) were clearly aggregated with a critical spatial scale of ca 25,m, and approximately nine randomly distributed tree clusters were identified. As expected from their marking behaviors, the spatial patterns of fecal deposition varied widely among mammal species. Whereas badger feces and dispersed seeds were clearly clustered at small spatial scales (<10,m), boar and fox feces were relatively scattered across the plot. A toroidal shift null model testing for independence indicated that boars tended to deliver seeds to the vicinity of adult trees and thus could contribute to the maintenance and enlargement of existing tree clusters. Badgers delivered feces and seeds in a highly clumped pattern but unlike boars, away from P. bourgaeana neighborhoods; thus, they are more likely to create new tree clusters than boars. The strong tree aggregation is likely to be the result of one or several non-exclusive processes, such as the spatial patterning of seed delivery by dispersers and seedling establishment beneath mother trees. In turn, the distinctive distribution of P. bourgaeana in Doñana appeared to interact with the foraging behavior of its mammalian seed dispersers, leading to neighbourhood-specific dispersal patterns and fruit-removal rates. Our study exemplifies how a detailed description of patterns generates testable hypotheses concerning the ecology of zoochorous. Pyrus bourgaeana dispersers were unique and complementary in their spatial patterning of seed delivery, which likely confers resilience to their overall service and suggests lack of redundancy and expendability of any one species. [source] Comparative life-history traits in a fig wasp community: implications for community structureECOLOGICAL ENTOMOLOGY, Issue 2 2010MAHUA GHARA 1. Whether life-history traits can determine community composition and structure is an important question that has been well explored theoretically, but has received scant empirical attention. Life-history traits of a seven-member community of galler and parasitoid fig wasp species (Chalcidoidea), developing within the inflorescences (syconia) of Ficus racemosa (Moraceae) in India, were determined and used to examine community structure and ecology. 2. Gallers were pro-ovigenic (all eggs are mature upon adult emergence) whereas parasitoids were synovigenic (eggs mature progressively during adult lifespan). Initial egg load was correlated with body size for some species, and there was a trade-off between egg number and egg size across all species. Although all species completed their development and left the syconium concurrently, they differed in their adult and pre-adult lifespans. Providing sucrose solutions increased parasitoid lifespan but had no effect on the longevity of some galler species. While feeding regimes and body size affected longevity in most species, an interaction effect between these variables was detected for only one species. 3. Life-history traits of wasp species exhibited a continuum in relation to their arrival sequence at syconia for oviposition during syconium development, and therefore reflected their ecology. The largest number of eggs, smallest egg sizes, and shortest longevities were characteristic of the earliest-arriving galling wasps at the smallest, immature syconia; the converse characterised the later-arriving parasitoids at the larger, already parasitised syconia. Thus life history is an important correlate of community resource partitioning and can be used to understand community structure. 4. This is the first comprehensive study of life-history traits in a fig wasp community. The comparative approach revealed constraints and flexibility in trait evolution. [source] Host plant specificity in several species of generalist mite predatorsECOLOGICAL ENTOMOLOGY, Issue 6 2001J. J. Beard Summary 1. Species in the genus Neoseiulus are considered to be generalist predators, with some species used in biological control programmes against phytophagous mites and insects. 2. A general survey of Neoseiulus species in inland Australia indicated that different species are associated with particular tree species. This pattern of host plant use was investigated for four Neoseiulus species (N. buxeus, N. cappari, N. brigarinus, N. eremitus) by means of a sampling programme through time and across space. 3. Each species of Neoseiulus was collected entirely or mostly from one species of tree; little or no overlap was detected despite the tree species growing in well-mixed stands. Host plant specificity thus appears to be strong in this genus. 4. Species in two other genera (Pholaseius and Australiseiulus), also considered to be predatory, showed a similar association with particular tree species. 5. The implications for the use of these predators in biological control are considerable. In particular, phytoseiid species with specific needs in terms of host plants may not be suitable for use as general purpose predators. Meeting the needs of phytoseiids through the modification of host plant attributes may be a step towards enhancing their efficacy as biological control agents. [source] A new optimal foraging model predicts habitat use by drift-feeding stream minnowsECOLOGY OF FRESHWATER FISH, Issue 1 2002G. D. Grossman Abstract , There is substantial need for models that accurately predict habitat selection by fishes for purposes ranging from the elaboration of ecological theory to the preservation of biodiversity. We have developed a new and highly tractable optimal foraging model for drift-feeding fishes that is based on the profitability of occupying varying focal-point velocities in a stream. The basic model can be written as: Ix = (Ex * Px) = {(D * A * V) * [1/(1 + e(b + cV))]} , Sx, where: (1) Ix is the net energy intake at velocity x; (2) E is prey encounter rate; (3) P is prey capture success rate which can be modelled as 1/(1 + e(b + cV)) where b and c are fitting constants from the prey capture success curve; (4) D is the energy content of prey (J/m3) in the drift; (5) A is the visual reactive area of the fish; (6) V is velocity (cm/s); and (7) S is the cost of maintaining position (J/s). Given that D, A and S can be considered constant over the range of velocities occupied by these fishes, the model reduces to e(b + cV) = 1/(cV , 1) which we solved iteratively to yield an optimal focal-point velocity for species in each sample. We tested the model by comparing its predictions to the mean focal-point velocities (i.e. microhabitats) occupied by four species of drift-feeding minnows in two sites in a stream in North Carolina, USA. The model successfully predicted focal-point velocities occupied by these species (11 out of 14 cases) in three seasonal samples collected over 2 years at two sites. The unsuccessful predictions still were within 2 cm/s of the 95% confidence intervals of mean velocities occupied by fishes, whereas the overall mean deviation between optimal velocities and mean fish velocities was small (range = 0.9 and 3.3 cm/s for the warpaint shiner and the Tennessee shiner, respectively). Available focal-point velocities ranged from 0,76 to 0,128 cm/s depending on site and season. Our findings represent one of the more rigorous field tests of an optimal foraging/habitat selection model for aquatic organisms because they encompass multiple species and years, and for one species, multiple sites. Because of the ease of parameterization of our model, it should be readily testable in a range of lotic habitats. If validated in other systems, the model should provide critical habitat information that will aid in the management of riverine systems and improve the performance of a variety of currently used management models (e.g. instream flow incremental methodology (IFIM) and total maximum daily load calculations (TMDL)). Resumen 1. Existe una grave necesidad de modelos que predigan con precisión la selección de hábitat por parte de los peces con fines que van del desarrollo de la teoría ecológica a la conservación de la biodiversidad. Nosotros hemos desarrollado un modelo nuevo y de fácil manejo de alimentación óptima para peces que se alimentan de la deriva que se fundamenta en los diferentes beneficios energéticos derivados de ocupar velocidades focales distintas en un río. 2. El modelo básico puede formularse como: Ix = (Ex * Px) = {(D * A * V) * [1/(1 + e(b + cV))]} , Sx, donde: (1) Ix es el energía neta obtenida a la velocidad, x; (2) V es la velocidad (cm/s); (3) A es el area visual de reacción del pez; (4) D es la energía contenida en las presas (J/m3) en la deriva; (5) E es la tasa de encuentro de presas; (6) P es la probabilidad de captura de la presa, que puede representarse como 1/(1 + e(b + cV)) donde b y c son constantes; y (7) S es el coste de nadar para mantener la posición en la corriente (J/s). Puesto que D, A y S pueden considerarse constantes en el rango de velocidades que ocupan estos peces, el modelo se reduce a e(b + cV) = 1/(cV , 1) que resolvimos iterativamente para obtener una velocidad focal óptima para cada especie en cada muestreo. 3. Probamos el modelo comparando su predicciones con la velocidades focales medias (i.e. microhabitats) ocupadas por cuatro especies de ciprínidos que se alimentan de la deriva en un río de Carolina del Norte. El modelo predijo con éxito las velocidades focales ocupadas por estas especies (11/14 casos) en tres muestreos estacionales llevados a cabo a lo largo de dos años en dos estaciones. Incluso las predicciones fallidas se diferenciaron en menos de 2 cm/s del límite de confianza al 95% CIs de las velocidades medias ocupadas, y la diferencia media entre predicciones y observaciones fue pequeña (rango = 0.9 cm/s warpaint shiner, a 3.3-cm/s Tennessee shiner). El rango de las velocidades focales medias disponibles fue de 0,76 cm/s a 0,128 cm/s dependiendo de la localidad y estación del año. 4. Nuestros resultados son una de las pruebas de campo más rigurosas de un modelo de alimentación óptima/selección de hábitat para organismos acuáticos puesto que incluyen diversas especies, años y, para una de las especies, localidades. La facilidad de la estima de los parámetros del modelo hace que sea fácil probarlo en diversos hábitats lóticos. Si es validado en ellos, el modelo debería proporcionar información valiosa que ayudará a la gestión de los sistemas fluviales y mejorará los resultados obtenidos a través de varios modelos usados actualmente para la gestión (p.e. IFIM y cálculos TMDL). [source] Interspecific competition among urban cockroach speciesENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2004Stéphane Boyer Abstract The aim of this study was to quantify and to compare the effects of intraspecific and interspecific competition among pairs of urban cockroaches [Blatta orientalis L., Periplaneta americana (L.), and Periplaneta australasiae Fabricius (Dictyoptera: Blattodea)] in relation to the limitation of resources such as shelter or food. Our approach was to assess whether the presence of one species affected the resource exploitation of another. A reduction in access to shelters or to food for one species revealed dominant/subordination relationships among species and induced spatial segregation in shelters and temporal segregation during food exploitation. The fragmentation of available resources facilitated spatial segregation and the access of more individuals of the subordinate species. Individuals of each species were aware of the presence of non-conspecifics. The outcome of interspecific competition under laboratory conditions should help us to understand how segregated spatial distributions occur under natural conditions in urban areas. [source] Systematic study of the genus Cyphononyx (Hymenoptera: Pompilidae) occurring in JapanENTOMOLOGICAL SCIENCE, Issue 2 2004Akira SHIMIZU Abstract Generic characteristics and phylogenetic relationships of the genus Cyphononyx are presented, together with a brief review of the biology of the genus. It is shown that only one species of the genus, C. fulvognathus (Rohwer), occurs in Japan. This species is distributed also in Taiwan and south China, and has hitherto been recognized under the name of C. dorsalis. In addition, two new combinations are presented: Cyphononyx hirtus (Haupt, 1935) (= Cryptochilus hirtus Haupt) and Cyphononyx plebejus (de Saussure, 1867) (= Agenia plebeja de Saussure), both of which were recorded from the Oriental Region. [source] Wilson's Storm Petrels Oceanites oceanicus Recognise the Olfactory Signature of Their MateETHOLOGY, Issue 12 2007Pierre Jouventin Chemical signals in birds have rarely been considered as recognition cues. Nevertheless, recent experiments showed that several petrel species are able to recognize their nest by smell, and in at least one species even their mate. But the use of smell may be different across the petrel species and olfactory nest recognition appears to be dependent on species' breeding biology. To increase our knowledge of individual olfactory recognition in petrels and the relationships between breeding biology and use of smell, we tested Wilson's storm petrels Oceanites oceanicus in Antarctica. In previous experiments, these birds failed to home if rendered anosmic, but the method employed to obtain anosmia (potentially stressing birds) and the fact that they breed in 24-h daylight suggest that they might use visual, rather than olfactory, cues to recognize their nest. Our birds were tested in T-maze experiments where nest odours or partner odours were presented. Wilson's storm petrels preferred odours of their own nest and mate. Results on olfactory nest recognition confirm and complete previous results, viz. anosmic Wilson's storm petrels do not home. Storm petrels olfactory mate recognition suggests that this ability may be widespread in burrowing petrels and implements olfactory nest recognition. [source] EVOLUTION OF CHARACTER DISPLACEMENT IN SPADEFOOT TOADS: DIFFERENT PROXIMATE MECHANISMS IN DIFFERENT SPECIESEVOLUTION, Issue 8 2010David W. Pfennig Character displacement occurs when two species compete, and those individuals most dissimilar from the average resource-use phenotypes of the other species are selectively favored. Few studies have explored the sequence of events by which such divergence comes about. We addressed this issue by studying two species of spadefoot toads that have undergone ecological character displacement with each other. Previous research revealed that phenotypic shifts between sympatric and allopatric populations of one species, Spea multiplicata, reflect a condition-dependent maternal effect. Here, we show that analogous shifts in the other species, S. bombifrons, cannot similarly be explained by such a maternal effect, and that these shifts instead appear to be underlain by allelic differences. We hypothesize that these two species have evolved different mechanisms of character displacement because they differ in duration in sympatry. Specifically, because they occur at the edge of a range expansion, populations of S. bombifrons have been exposed to S. multiplicata for a longer period. Consequently, S. bombifrons have likely had more time to accumulate genetic changes that promote character displacement. Generally, character displacement may often progress through an initial phase in which trait differences are environmentally induced to one in which they are constitutively expressed. [source] A TEST OF WORKER POLICING THEORY IN AN ADVANCED EUSOCIAL WASP, VESPULA RUFAEVOLUTION, Issue 6 2005T. Wenseleers Abstract Mutual policing is an important mechanism for maintaining social harmony in group-living organisms. In some ants, bees, and wasps, workers police male eggs laid by other workers in order to maintain the reproductive primacy of the queen. Kin selection theory predicts that multiple mating by the queen is one factor that can selectively favor worker policing. This is because when the queen is mated to multiple males, workers are more closely related to queen's sons than to the sons of other workers. Here we provide an additional test of worker policing theory in Vespinae wasps. We show that the yellowjacket Vespula rufa is characterized by low mating frequency, and that a significant percentage of the males are workers' sons. This supports theoretical predictions for paternities below 2, and contrasts with other Vespula species, in which paternities are higher and few or no adult males are worker produced, probably due to worker policing, which has been shown in one species, Vespula vulgaris. Behavioral observations support the hypothesis that V. rufa has much reduced worker policing compared to other Vespula. In addition, a significant proportion of worker-laid eggs were policed by the queen. [source] DIFFERENTIAL PATTERNS OF INTROGRESSION ACROSS THE X CHROMOSOME IN A HYBRID ZONE BETWEEN TWO SPECIES OF HOUSE MICEEVOLUTION, Issue 9 2004Bret A. Payseur Abstract A complete understanding of the speciation process requires the identification of genomic regions and genes that confer reproductive barriers between species. Empirical and theoretical research has revealed two important patterns in the evolution of reproductive isolation in animals: isolation typically arises as a result of disrupted epistatic interactions between multiple loci and these disruptions map disproportionately to the X chromosome. These patterns suggest that a targeted examination of natural gene flow between closely related species at X-linked markers with known positions would provide insight into the genetic basis of speciation. We take advantage of the existence of genomic data and a well-documented European zone of hybridization between two species of house mice, Mus domesticus and M. musculus, to conduct such a survey. We evaluate patterns of introgression across the hybrid zone for 13 diagnostic X-linked loci with known chromosomal positions using a maximum likelihood model. Interlocus comparisons clearly identify one locus with reduced introgression across the center of the hybrid zone, pinpointing a candidate region for reproductive isolation. Results also reveal one locus with high frequencies of M. domesticus alleles in populations on the M. musculus side of the zone, suggesting the possibility that positive selection may act to drive the spread of alleles from one species on to the genomic background of the other species. Finally, cline width and cline center are strongly positively correlated across the X chromosome, indicating that gene flow of the X chromosome may be asymmetrical. This study highlights the utility of natural populations of hybrids for mapping speciation genes and suggests that the middle of the X chromosome may be important for reproductive isolation between species of house mice. [source] The identity of Paeonia corsica Sieber ex Tausch (Paeoniaceae), with special reference to its relationship with P. mascula (L.) Mill.FEDDES REPERTORIUM, Issue 1-2 2006Hong De-Yuan The taxonomy of the genus Paeonia in central Mediterranean islands has been controversial, with number of recognized taxa changing greatly from one species without infraspecific division to three species or five infraspecific taxa in one species, and with the number of synonyms as great as 30. In the present work, the taxonomic history is thoroughly reviewed and a taxonomic revision is made based on extensive field work, chromosome observation, population sampling, examination of a large amount of herbarium specimens, and subsequent statistic analysis. As a result of the studies P. corsica Sieber ex Tausch, an ignored specific name, is restored at specific rank, and the species is found distinct from all the three subspecies of P. mascula in this region in having mostly nine (vs , 10) leaflets/segments, shorter hairs (1.5 mm vs 3 mm long) on carpels, rather densely holosericeous (vs glabrous or very sparsely hirsute) on the lower surface of leaves. It is a diploid, confined to Corsica France), Sardinia (Italy), Ionian Islands and Akarnania Province of Greece, whereas P. mascula is a tetraploid, widely distributed from Spain to Turkey and Iraq, but not in Corsica, Sardinia and W Greece. In addition, type specimens of four taxa are designated, and 29 botanic names are listed as synonyms of P. corsica in this paper. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Die Identität von Paeonia corsica Sieber ex Tausch (Paeoniaceae), mit besonderem Bezug auf ihre Verwandtschaft mit P. mascula (L.) Mill. Die Taxonomie der Gattung Paeonia auf den zentralen Mittelmeerinseln ist stets kontrovers gewesen. Die Anzahl der Taxa wechselte zwischen einer Art ohne infraspezifische Differenzierung bis zu drei oder fünf infraspezifische Taxa innerhalb einer Art. Die Anzahl der Synonyme beträgt bis zu 30 Taxa. In vorliegender Arbeit wird die Geschichte der Taxonomie sorgfältig betrachtet und eine taxonomische Revision auf der Basis extensiver Feldstudien, Chromosomen-Bewertung, Sammlungen von Populationen, der Untersuchung zahlreicher Herbarproben und abschließender statistischer Analysen vorgenommen. Im Ergebnis dieser Untersuchungen wird Paeonia corsica Sieber ex Tausch, ein bislang unbeachteter Artname, erneut in den Rang einer Art erhoben. Diese in dieser Region gefundene Spezies wurde als verschieden von den drei Unterarten von Paeonia mascula befunden. Sie hat meist neun (, 10) Blättchen, kürzere Haare (1.5 mm vs 3 mm lang) auf dem Karpell dichtere holoserios (vs glabrous oder selten hirsut) auf der Blattunterseite. Paeoniacorsica ist diploid auf Korsika (Frankreich), Sardinien (Italien), den Ionischen Inseln und der Provinz Akarnania in Griechenland, während Paeonia mascula tetraploid ist und weit verbreitet von Spanien bis in die Türkei und den Irak, fehlt aber auf Korsika, Sardinien und in Westgriechenland. Außerdem werden Typspecimen für 4 Taxa festgelegt. Als Synonyme von P. corsica wurden 29 Namen aufgelistet. [source] Mycosphaerella species associated with leaf disease of Eucalyptus globulus in EthiopiaFOREST PATHOLOGY, Issue 4 2006Alemu Gezahgne Summary Eucalyptus spp. are among the most widely planted exotic trees in Ethiopia. Several damaging leaf pathogens are known from Eucalyptus spp. worldwide. Of these, Mycosphaerella spp. are among the most important, causing the disease known as Mycosphaerella leaf disease (MLD). Characteristic symptoms of MLD include leaf spot, premature defoliation, shoot and twig dieback. Recent disease surveys conducted in Ethiopian Eucalyptus plantations have revealed disease symptoms similar to those caused by Mycosphaerella spp. These symptoms were restricted to E. globulus trees growing in several localities in south, south western and western Ethiopia. The aim of this study was to identify the fungi associated with this disease. This was achieved by examining ascospore germination patterns, anamorph associations and sequence data from the Internal Transcribed Spacer (ITS) region of the rRNA operon, for representative isolates. Several different ascospore germination patterns were observed, suggesting that more than one species of Mycosphaerella is responsible for MLD on E. globulus in Ethiopia. Analysis of sequence data showed that three Mycosphaerella spp., M. marksii, M. nubilosa and M. parva were present. This is the first report of these three species from Ethiopia and represents a valuable basis on which to build further studies in the region. Résumé Les Eucalyptus comptent parmi les essences d'arbres exotiques les plus plantées en Ethiopie. Plusieurs pathogènes foliaires sont connus dans le monde pour occasionner des dégâts sur Eucalyptus. Parmi ceux-ci, les espèces de Mycosphaerella sont parmi les plus importantes, causant la maladie connue comme Maladie Foliaire àMycosphaerella (MFM, MLD en anglais). Les symptômes caractéristiques de la MFM comprennent des taches foliaires, une défoliation précoce et des dépérissements de pousses et de rameaux. Des campagnes de surveillance menées récemment dans les plantations éthiopiennes d'Eucalyptus ont révélé la présence de tels symptômes. Ces symptômes sont uniquement observés sur E. globulus dans plusieurs localités du sud, sud-ouest et ouest de l'Ethiopie. L'objectif de cette étude était d'identifier les champignons associés à cette maladie. Pour cela, des isolats représentatifs ont étéétudiés pour les modalités de germination des ascospores, les anamorphes associés ainsi que les données de séquence de la région ITS de l'opéron ADNr. Différentes modalités de germination des ascospores ont été observées, suggérant que plusieurs espèces de Mycosphaerella seraient associées à la MFM sur E. globulus en Ethiopie. L'analyse des données de séquence a montré la présence de 3 espèces : M. marksii, M. nubilosa et M. parva. Ceci constitue la première mention de ces 3 espèces en Ethiopie et une première étape pour envisager d'autres études dans cette région. Zusammenfassung Eucalyptus -Arten sind die am häufigsten angepflanzten exotischen Bäume in Äthiopien. An Eucalyptus kommen verschiedene Blattkrankheiten vor, wobei die Mycosphaerella -Arten als Verursacher der Mycosphaerella -Blattkrankheit (MLD) am bedeutendsten sind. Charakteristische Symtpome der MLD sind Blattnekrosen und vorzeitiger Blattfall sowie Trieb- und Zweigsterben. Bei der Inventur von Krankheiten in äthiopischen Eucalyptusplantagen wurden Symptome entdeckt, die denen von Mycosphaerella spp. ähnlich waren. Diese traten nur an E. globulus lokal in S-, SW- und W-Äthiopien auf. Ziel dieser Untersuchung war es, die damit assoziierten Pilze zu identifizieren. Hierzu wurde an repräsentativen Isolaten das Keimverhalten der Ascosporen, das Vorkommen von Anamorphen und die ITS-Sequenz des rRNA-Operons untersucht. Es wurden verschiedene Keimungstypen der Ascosporen beobachtet, was darauf schliessen liess, dass mehr als eine Mycosphaerella -Art für die Krankheit an E. globulus in Äthiopien verantwortlich ist. Anhand der Sequenzen wurden M. marksii, M. nubilosa und M. parva identifiziert. Dies ist der Erstnachweis für diese drei Arten in Äthiopien und eine Grundlage für weitere Studien. [source] Habitat selection as a source of inter-specific differences in recruitment of two diadromous fish speciesFRESHWATER BIOLOGY, Issue 11 2008ROBIN HALE Summary 1For aquatic species with highly dispersive offspring, the addition of new individuals into an area (recruitment) is a key process in determining local population size so understanding the causes of recruitment variability is critical. While three general causative mechanisms have been identified (the supply of individuals, habitat selection and mortality), we have a limited understanding of how variation in each is generated, and the consequences this may have for the spatial and temporal distribution of recruits. 2We examined whether active habitat selection during settlement could be the cause of variability in populations of two diadromous fish species using a field survey and laboratory-based choice experiments. If larval behaviour is important, we predicted there would be inter-specific differences in abundance between sites during the survey, and that larvae would prefer water collected from sites with higher conspecific abundances during the experiments. 3During the field survey, significant differences were detected between two rivers (the Cumberland and Grey), with one species (Galaxias maculatus) found in higher abundances at one site (the Cumberland River) while comparable numbers of a closely related species (Galaxias brevipinnis) were caught at both sites. Laboratory choice experiments were conducted to determine whether larval preferences during settlement could be the cause of these differences. G. maculatus larvae showed a preference for freshwater over saltwater, indicating that the fish may be responding to reduced salinities around river mouths during settlement. The results of a second experiment were consistent with the notion that larval preferences could be the mechanism driving differences in the populations of the two rivers, with G. maculatus preferring water collected from the Cumberland River while G. brevipinnis did not prefer water from either river. 4These results demonstrate that active habitat selection may be important in establishing spatial patterns of larvae at settlement, and that multiple cues are likely to be involved. This study also demonstrates that the behaviours exhibited by individuals can strongly influence the structure and dynamics of populations of aquatic species with complex life cycles. [source] Is water temperature an adequate predictor of recruitment success in cyprinid fish populations in lowland rivers?FRESHWATER BIOLOGY, Issue 4 2003A. D. Nunn SUMMARY 1. Higher than average ambient water temperature in the first year of life may be responsible for strong cohorts of adult cyprinid fish. Whilst temperature explains much of the variation in year-class strength (YCS), however, it is not the only influential factor as high temperature does not inevitably yield strong year-classes. Furthermore, years in which a strong year-class is prevalent in one species do not necessarily result in strong year-classes in other coexisting species, suggesting other biotic and abiotic factors are important in regulating recruitment success. 2. The relationships between water temperature, river discharge, the position of the Gulf Stream, 0-group fish growth and recruitment success (YCS) were examined in three cyprinid fish species in an English lowland river, using a 15-year data set. 3. Mean length of 0-group fish at the end of the summer was positively correlated with water temperature (cumulative degree-days >12 °C) and negatively correlated with river discharge (cumulative discharge-days above basal discharge rate). Water temperature was negatively correlated with river discharge. 4. YCS was positively correlated with mean 0-group fish length at the end of the summer and with the position of the North Wall of the Gulf Stream. 5. 'Critical periods' (i.e. periods in the first summer of life when fish may be more susceptible to increases in river discharge) were difficult to discern because of interannual variations in river discharge relative to the timing of fish hatching. YCS of roach and chub was most strongly correlated with discharge in the period from June to September inclusive, while YCS of dace was most significantly correlated with discharge in August. 6. River discharge (rather than water temperature) may be the key factor in determining YCS, either directly (through discharge-induced mortality) or indirectly (via reduced growth at lower water temperatures, discharge-associated increases in energy expenditure or reduced food availability). It could be that, in effect, water temperature determines potential YCS while discharge determines realised YCS. 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