952 resultados para Macroinvertebrates Taxonomy Sufficiency


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Multilocus enzyme electrophoresis (MLEE) has been used in the study of some Bacillus species. In this work we applied MLEE and numerical analysis in the study of the Bacillus sphaericus group. B. sphaericus can be distinguished from other entomopathogenic Bacillus by a unique allele (NP-4). Within the species, all insect pathogens were recovered in the same phenetic cluster and all of these strains have the same band position (electrophoresis migration) on the agarose gel (ADH-2). The entomopathogenic group of B. sphaericus seems to be a clonal population, having two widespread frequent genotypes (zymovar 59 and zymovar 119).

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Despite opportunities for radiation provided by spatio-temporal isolation, the basic morphological plan of pulmonate snails has remained conservative. In consequence of the resulting dearth of morphological characters and their plasticity, there is a case for using biochemical characters such as exogenous chemicals released by the snails (e.g. amino acids) and their chemoreception niche as taxonomic aids to classify snails of medical importance. As these same chemicals are used by snails to distinguish conspecifics they could also be used as "environmental antibodies" in controlled release formulations (CRF's) designed to remove target snails in a specific, cost-effective and ecologically acceptable manner. The snails, surface-living bacteria, algae and macrophytic plants are considered as co-evolved, interactive modular systems with strong mutualistic elements. Recently, anthropogenic perturbations such as deforestation, and damming of flowing waters, have benefited these modules whereas others such as river canalization, acid deposition, accumulation of pesticide residues and eutrophication have harmed them. Research is needed to elucidate the factors which limit the growth of snails in primitive habitats, uninfluenced by man, as well as in those subject to harmful anthropogenic factors. The understanding thus gained could be applied to develop cost-effective primary health care strategies to reduce or prevent transmission of schistosomiasis and other water related diseases.

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A l’actualitat trobem nombrosos sistemes aquàtics alterats per diferents efectes d’origen antropogènic. Per tal d’evitar i/o disminuir aquests efectes va sorgir la Directiva Marc de l’Aigua (2000/60/CE) essent aquest un dels seus objectius. Aquest article descriu el funcionament hidrogeològic i l’estat ecològic de la riera de Santa Coloma, afluent de la Tordera (NE Catalunya), des de pràcticament el seu inici a Santa Coloma de Farners (Girona) fins a Riudarenes (Girona). S’intenta establir les possibles influències del funcionament hidrogeològic en l’estat ecològic a partir de dades piezomètriques, de cabal, fisicoquímiques i biològiques. Per aquesta última part s’han utilitzat indicadors biològics com l’índex d’hàbitat fluvial (IHF), avaluant l’hàbitat físic; l’índex de Qualitat del Bosc de Ribera (QBR), per determinar la qualitat ecològica de la zona de ribera; l’índex Biological Monitorig Working Party per a conques internes de Catalunya (BMWPC), per avaluar les diferents famílies de macroinvertebrats que hi viuen i l’índex ECOSTRIMED, una síntesi dels dos índex anteriors.

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Two sibling species of Biomphalaria, B. tenagophila and B. occidentalis were identified using isozyme patterns obtained by horizontal gel electrophoresis. Six diagnostic enzymatic loci were identified in digestive gland homogenates. The results enable us to distinguish the species, calculate the Nei's coefficient of genetic similarity, and provide a basis for making inferences about the pattern of these two planorbid species colonization and distribution.

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Wyeomyia (Dendromyia) luteoventralis is redescribed from females, males, larvae and pupae collected at the type locality, in Brazil, and compared to the closely related species. At least six species - Wy. luteoventralis, Wy. ypsipola, Wy. testei, Wy. trifurcata, Wy. complosa and Wy. jocosa - appparently, belong to a monophyletic group, the subgenus Dendromyia. All other species previously included in Dendromyia are hereby excluded from this subgenus and retained in genus Wyeomyia without subgeneric placement.

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Dichelacera (Dichelacera) corumbaensis n. sp. is described from two female specimens collected in the urban area of Corumbá city, state of Mato Grosso do Sul. This is one of the six species of Dichelacera occuring in the state and the twenty-eighth species of the subgenus known from Brazil. The head in lateral view, frons, antenna, palpi and wings are illustrated. A differential diagnosis is given related to D. rubricosa, D. unifasciata, D. albifasciata and d. fuscipes.

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A description is given of the shell, renal organ, reproductive system and radula of topotypic specimens of Lymnaea cousini Jousseaume, 1887. A diagnosis between it and four other lymnaeids which also occur in South America and were previously studied by the author (L. columella, L. diaphana, L. viatrix and L. rupestris) is presented.

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A description is given of the shell, head-foot, pulmonary wall, reproductive system and radula of Biomphalaria subprona (Martens, 1899). A diagnosis between it and two other congeneric species under 10 mm in shell diameter occurring in Middle America (Biomphalaria helophila and B. schrammi) is presented.

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Lutzomyia (Nyssomyia) intermedia (Lutz & Neiva) is redescribed, a neotype is designated, and a very similar species, L. (N.) neivai (Pinto, 1926), is resurrected; the male and the female are redescribed. The two species can be differentiated by differences in the spermathecae, common ducts and number of cibarial horizontal teeth of the females and in the size and proportions of several structures of both sexes. The known geographical distribution of both species is given.

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In an attempt to isolate Paracoccidioides brasiliensis from nature 887 samples of soil from Botucatu, SP, Brazil, were collected cultured in brain heart infusion agar supplemented with dextrose, in potato dextrose agar and in yeast extract starch dextrose agar, all with antibiotics, at 25º and 37ºC. Five thermo-dependent dimorphic fungi morphologically resembling P. brasiliensis were isolated; two from armadillo holes; further studies of the biology, antigenicity and genetic features of the five dimorphic fungi are necessary to clarify their taxonomy and their possible relation to P. brasiliensis. In addition, 98 dematiaceous fungi and 581 different species of Aspergillus spp. were also isolated. Our findings emphasize that armadillos and their environment are associated with thermo-dimorphic fungi and confirm the ubiquity of pathogenic dematiaceous fungi and Aspergillus spp.

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A male of Triatoma ryckmani Zeledón & Ponce, 1972, was studied by scanning electron microscopy. Only few specimens of this species are known. In this paper, some structures from the head, thorax, abdomen and distal region of the second leg are shown. Some of them could have taxonomic importance, as the oculo-ocellar region, the buccula, the anterolateral angle of the collar, the scutellum with the process longer than the main body, the stridulatory sulcus with an unusual backward vermiform area, and the tibia-tarsal articulation, with a spongy fossula. The last structure was absent in specimens previously studied (Lent & Wygodzinsky 1979). Differences between this specimen and others previously described by several authors are dicussed.

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Morphological description of sand flies has remained a neglected area. The different organs used in taxonomy have not yet been described adequately with the scanning electron microscopy (SEM). We have examined the external genital structures of females of three Old World phlebotomine sand flies under SEM and recorded the morphological variations of the organs. We have found the female external genital structures of the three species varied considerably in morphology. The importance of the female external genital structures in sand fly identification is indicated

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Menorca és una illa del Mediterrani occidental i una important destinació turística. El turisme estival és un pilar de l’economia de l’illa i té implicacions en tots els aspectes d’aquesta. Una bona part dels turistes es concentren en nuclis turístics costaners dedicats a una única activitat (l’allotjament de turistes). En aquest projecte s’estudien els consums i els potencials de captació d’aigua i energia de cinc nuclis turístics menorquins i alguns dels seus establiments turístics i se n’avalua el potencial d’autosuficiència. També es fa un estudi de mobilitat dels turistes, a partir del qual es quantifica el cost energètic de la mobilitat i les emissions de CO2 que se’n deriven. Les eines utilitzades han estat enquestes i Sistemes d’Informació Geogràfica. Els resultats mostren que el consum hídric per persona és molt variable (de 98 a 466 litres diaris). El consum elèctric per persona és més homogeni que el d’aigua (entre 5 i 10 kWh·persona-1·dia-1 a nivell de nucli turístic) i presenta valors superiors en allotjaments del tipus hotel que del tipus apartaments. Els trajectes d’anada i tornada a l’illa amb avió o vaixell representen més del 80% del cost energètic total de les vacances a Menorca (aprox. 1 MWh per estada) i de les emissions de CO2 associades. Els turistes espanyols recorren un 180% més de distància en desplaçaments a l’interior de l’illa que els d’altres nacionalitats. L’aprofitament d’aigües pluvials podria cobrir menys del 25% de les necessitats hídriques de la majoria d’allotjaments turístics i entre el 28 i el 36% de les necessitats hídriques totals dels nuclis turístics, mantenint-se els nivells actuals de consum. La captació d’energia solar fotovoltaica in situ podria arribar a suplir entre el 50 i el 90% del consum d’energia elèctrica en els nuclis turístics i fins al 100% del mateix en alguns allotjaments turístics.

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Aquest projecte té com a objectiu l’estudi de l’estat ambiental dels hotels del municipi de Sitges i l’estudi d’aprofitament dels recursos hídrics i energètics característics d’aquesta zona del Mediterrani per hotels de 4 i 5 estrelles. Sitges és un municipi que al període estival dobla la població, i que amb una superfície de 43,85 Km2 conta amb 35 hotels i apart pensions, hostals i càmpings, per tant, el turisme és l’activitat més important a Sitges. Per desenvolupar aquest projecte s’ha realitzat una enquesta senzilla sobre qualitat ambiental per conèixer el comportament ambiental dels diferents hotels. En aquest estudi han participat 15 dels 35 hotels del municipi, ja que el 49% d’aquests romanen tancats des d’Octubre fins a Març i dels 18 hotels restants 15 han accedit a formar part d’aquest estudi. A través d’una prova pilot s’ha avaluat la implantació del Distintiu de Garantia de Qualitat Ambiental a l’hotel Antemare i a l’hotel Sunway Playa Golf, aquests dos hotels pertanyen a la categoria de quatre estrelles, categoria que reuneix més nombre d’hotels i el tant per cent d’ocupació és major en comparació amb les altres categories. El DGQA és una ecoetiqueta de serveis que atorga la Generalitat de Catalunya a partir de la revisió de l’establiment per mitjà d’un tècnic autoritzat. S’ha analitzat l’aprofitament dels recursos local com, les aigües pluvials i la radiació solar en els hotels de 4 i 5 estrelles per obtenir l’autosuficiència individual dels 9 hotels objecte d’estudi. Els resultats obtinguts en aquest estudi reflecteixen la possibilitat de millorar l’estat ambiental dels establiments hotelers, duent a terme alguns criteris bàsics com, la recollida selectiva i una major implantació d’energies renovables, així com també la utilització d’aquestes per assolir un cert nivell d’autosuficiència energètica i hídrica. La prova pilot mostra que els dos hotels estudiats estan molt a prop d’aconseguir el DGQA, els vectors on s’haurien de fer millores són, informació ambiental, energia, aigua i residus.

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SUMMARYIn the context of the biodiversity crisis, amphibians are experiencing the most severe worldwide decline of all vertebrates and are in urgent need of better management. Efficient conservation strategies rely on sound knowledge of the species biology and of the genetic and demographic processes that might impair their welfare. Nonetheless, these processes are poorly understood in amphibians. Delineating population boundaries remains consequently problematic for these species, while it is of critical importance to define adequate management units for conservation. In this study, our attention focused on the alpine salamander (Salamandra atra), a species that deserves much interest in terms of both conservation biology and evolution. This endemic alpine species shows peculiar life-history traits (viviparity, reduced activity period, slow maturation) and has a slow population turnover, which might be problematic for its persistence in a changing environment. Due to its elusive behaviour (individuals spend most of their time underground and are unavailable for sampling), dynamic processes of gene and individuals were poorly understood for that species. Consequently, its conservation status could hardly be reliably assessed. Similarly the fire salamander (Salamandra salamandra) also poses special challenges for conservation, as no clear demarcation of geographical populations exists and dispersal patterns are poorly known. Through a phylogeographic analysis, we first studied the evolutionary history of the alpine salamander to better document the distribution of the genetic diversity along its geographical range. This study highlighted the presence of multiple divergent lineages in Italy together with a clear genetic divergence between populations from Northern and Dinaric Alps. These signs of cryptic genetic differentiation, which are not accounted for by the current taxonomy of the species, should not be neglected for further definition of conservation units. In addition, our data supported glacial survival of the species in northern peripheral glacial réfugia and nunataks, a pattern rarely documented for long-lived species. Then, we evaluated the level of gene flow between populations at the local scale and tested for asymmetries in male versus female dispersal using both field-based (mark-recapture) and genetic approaches. This study revealed high level of gene flow between populations, which stems mainly from male dispersal. This corroborated the idea that salamanders are much better dispersers than hitherto thought and provided a well- supported example of male-biased dispersal in amphibians. In a third step, based on a mark- recapture survey, we addressed the problem of sampling unavailability in alpine salamanders and evaluated its impact on two monitoring methods. We showed that about three quarters of individuals were unavailable for sampling during sampling sessions, a proportion that can vary with climatic conditions. If not taken into account, these complexities would result in false assumptions on population trends and misdirect conservation efforts. Finally, regarding the daunting task of delineating management units, our attention was drawn on the fire salamander. We conducted a local population genetic study that revealed high levels of gene flow among sampling sites. Management units for this species should consequently be large. Interestingly, despite the presence of several landscape features often reported to act as barriers, genetic breaks occurred at unexpected places. This suggests that landscape features may rather have idiosyncratic effects on population structure. In conclusion, this work brought new insights on both genetic and demographic processes occurring in salamanders. The results suggest that some biological paradigms should be taken with caution when particular species are in focus. Species- specific studies remain thus fundamental for a better understanding of species evolution and conservation, particularly in the context of current global changes.RESUMEDans le contexte de la crise de la biodiversité actuelle, les amphibiens subissent le déclin le plus important de tous les vertébrés et ont urgemment besoin d'une meilleure protection. L'établissement de stratégies de conservation efficaces repose sur des connaissances solides de la biologie des espèces et des processus génétiques et démographiques pouvant menacer leur survie. Ces processus sont néanmoins encore peu étudiés chez les amphibiens.Dans cette étude, notre attention s'est portée sur la salamandre noire (Salamandra atra), une espèce endémique des Alpes dont les traits d'histoire de vie atypiques (viviparité, phase d'activité réduite, lent turnover des populations) pourraient la rendre très vulnérable face aux changements environnementaux. Par ailleurs, en raison de son comportement cryptique (les individus passent la plupart de leur temps sous terre) la dynamique des gènes et des individus est mal comprise chez cette espèce. Il est donc difficile d'évaluer son statut de conservation de manière fiable. La salamandre tachetée {Salamandra salamandra), pour qui il n'existe aucune démarcation géographique apparente des populations, pose également des problèmes en termes de gestion. Dans un premier temps, nous avons étudié l'histoire évolutive de la salamandre noire afin de mieux décrire la distribution de sa diversité génétique au sein de son aire géographique. Cela a permis de mettre en évidence la présence de multiples lignées en Italie, ainsi qu'une nette divergence entre les populations du nord des Alpes et des Alpes dinariques. Ces résultats seront à prendre en compte lorsqu'il s'agira de définir des unités de conservation pour cette espèce. D'autre part, nos données soutiennent l'hypothèse d'une survie glaciaire dans des refuges nordiques périglaciaires ou dans des nunataks, fait rarement documenté pour une espèce longévive. Nous avons ensuite évalué la différentiation génétique des populations à l'échelle locale, ce qui a révélé d'important flux de gènes, ainsi qu'une asymétrie de dispersion en faveur des mâles. Ces résultats corroborent l'idée que les amphibiens dispersent mieux que ce que l'on pensait, et fournissent un exemple robuste de dispersion biaisée en faveur des mâles chez les amphibiens. Nous avons ensuite abordé le problème de Γ inaccessibilité des individus à la capture. Nous avons montré qu'environ trois quarts des individus sont inaccessibles lors des échantillonnages, une proportion qui peut varier en fonction des conditions climatiques. Ignoré, ce processus pourrait entraîner une mauvaise interprétation des fluctuations de populations ainsi qu'une mauvaise allocation des efforts de conservation. Concernant la définition d'unités de gestion pour la salamandre tachetée, nous avons pu mettre en évidence un flux de gènes important entre les sites échantillonnés. Les unités de gestion pour cette espèce devraient donc être étendues. Etonnamment, malgré la présence de nombreuses barrières potentielles au flux de gènes, les démarcations génétiques sont apparues à des endroits inattendus. En conclusion, ce travail a apporté une meilleure compréhension des processus génétiques et démographiques en action chez les salamandres. Les résultats suggèrent que certains paradigmes biologiques devraient être considérés avec précaution quand il s'agit de les appliquer à des espèces particulières. Les études spécifiques demeurent donc fondamentales pour une meilleure compréhension de l'évolution des espèces et leur conservation, tout particulièrement dans le contexte des changements globaux actuels.