972 resultados para Artemisia genus


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Notes on the systematics of the orchid-bee genus Eulaema (Hymenoptera, Apidae). The classification of the genus Eulaema is modified in order to make it congruent with recent phylogenetic hypotheses based on molecular data. The speciosa group, containing E. peruviana, E. speciosa and related species, is removed from E. (Eulaema) and transferred to E. (Apeulaema). New morphological characters are presented to support the revised scope of the subgenera and their diagnostic features are revised. Six species groups are recognized herein: two in E. (Apeulaema) and four in E. (Eulaema). A list of valid species in each species group and an identification key to males of each of the subgenera and species groups are provided. Finally, an older overlooked designation of a type species for Eulaema is presented in the Appendix.

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Maternal care in Gargaphia decoris is described for the first time. A video is presented as supplementary material. The knowledge on such trait within Tingidae is summarized. The behavior within the family is discussed, and the potential as a source of phylogenetic characters for further analyses is stressed.

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ABSTRACT Two new species of the stingless bee genus Schwarziana from Brazil are described and illustrated. Schwarziana bocainensis sp. nov. is described from Serra da Bocaina, in São Paulo, and S. chapadensis sp. nov. is described from Chapada dos Veadeiros, in Goiás. An identification key to workers of the known species of Schwarziana is provided.

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ABSTRACT Moncini is the tribe of Hesperiidae that comprises the greatest diversity of small, brown, hard to identify skippers. The group is peculiarly classified as having many monotypic genera, thus offering low informative value to its systematics. This study presents a review of the genus Gallio Evans, 1955, a genus formerly recognized as monotypic, and describes three new species, Gallio imperatriz sp. nov. from Maranhão, Brazil, Gallio furtadoi sp. nov. from Mato Grosso, Brazil and Gallio eti sp. nov. from Madre de Díos, Peru and Acre, Brazil (type locality). A lectotype for Vehilius carasta Schaus, 1902 is designated. Gallio is therefore redescribed and illustrations and diagnosis to its species are provided.

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Starting from embryonic (protoconch-ammonitella) and early juvenile shells, which are indistinguishable at the species level, growth curves of Osperleioceras from the Reynesi Subzone (Upper Toarcian) of the Causses Basin (Aveyron, France) show a continuous radiating range of correlated variation in dimensional and ornamental characters, such as involution, whorl compression, rib strength and rib density. This covariation pattern can be observed among single-horizon assemblages, as well as during individual ontogenetic development. The existence of a continuous intergradational series of shells, ranging from stout coarsely ribbed to smooth suboxycone morphologies, rules out functional or ecological selectivity to explain this non-random variability pattern. The complex interdependence of shape and sculpture can be simulated by a model in which sculpture intensity depends on mantle curvature [GUEX, 1999]. The expression of covariation in subadult specimens since the base of Upper Toarcian reveals a rise in variability, concomitant with a size decrease, both contemporaneous with environmental instability. It developed in successive bursts from a fairly long low variability period spanning the whole Middle Toarcian.

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BACKGROUND: The majority of Haemosporida species infect birds or reptiles, but many important genera, including Plasmodium, infect mammals. Dipteran vectors shared by avian, reptilian and mammalian Haemosporida, suggest multiple invasions of Mammalia during haemosporidian evolution; yet, phylogenetic analyses have detected only a single invasion event. Until now, several important mammal-infecting genera have been absent in these analyses. This study focuses on the evolutionary origin of Polychromophilus, a unique malaria genus that only infects bats (Microchiroptera) and is transmitted by bat flies (Nycteribiidae). METHODS: Two species of Polychromophilus were obtained from wild bats caught in Switzerland. These were molecularly characterized using four genes (asl, clpc, coI, cytb) from the three different genomes (nucleus, apicoplast, mitochondrion). These data were then combined with data of 60 taxa of Haemosporida available in GenBank. Bayesian inference, maximum likelihood and a range of rooting methods were used to test specific hypotheses concerning the phylogenetic relationships between Polychromophilus and the other haemosporidian genera. RESULTS: The Polychromophilus melanipherus and Polychromophilus murinus samples show genetically distinct patterns and group according to species. The Bayesian tree topology suggests that the monophyletic clade of Polychromophilus falls within the avian/saurian clade of Plasmodium and directed hypothesis testing confirms the Plasmodium origin. CONCLUSION: Polychromophilus' ancestor was most likely a bird- or reptile-infecting Plasmodium before it switched to bats. The invasion of mammals as hosts has, therefore, not been a unique event in the evolutionary history of Haemosporida, despite the suspected costs of adapting to a new host. This was, moreover, accompanied by a switch in dipteran host.

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Information underlying analyses of coffee fertilization systems should consider both the soil and the nutritional status of plants. This study investigated the spatial relationship between phosphorus (P) levels in coffee plant tissues and soil chemical and physical properties. The study was performed using two arabica and one canephora coffee variety. Sampling grids were established in the areas, and the points georeferenced. The assessed properties of the soil were levels of available phosphorus (P-Mehlich), remaining phosphorus (P-rem) and particle size, and of the plant tissue, phosphorus levels (foliar P). The data were subjected to descriptive statistical analysis, correlation analysis, cluster analysis, and probability tests. Geostatistical and trend analyses were only performed for pairs of variables with significant linear correlation. The spatial variability for foliar P content was high for the variety Catuai and medium for the other evaluated plants. Unlike P-Mehlich, the variability in P-rem of the soil indicated the nutritional status of this nutrient in the plant.

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Coevolution is among the main forces shaping the biodiversity on Earth. In Eurasia, one of the best-known plant-insect interactions showing highly coevolved features involves the fly genus Chiastocheta and its host-plant Trollius. Although this system has been widely studied from an ecological point of view, the phylogenetic relationships and biogeographic history of the flies have remained little investigated. In this integrative study, we aim to test the monophyly of the five Chiastocheta eco-morphological groups, defined by Pellmyr in 1992, by inferring a mitochondrial phylogeny. We further apply a new approach to assess the effect of (i) different molecular substitution rates and (ii) phylogenetic uncertainty on the inference of the spatio-temporal evolution of the group. From a taxonomic point of view, we demonstrate that only two of Pellmyr's groups (rotundiventris and dentifera) are phylogenetically supported, the other species appearing para- or polyphyletic. We also identify the position of C. lophota, which was not included in previous surveys. From a spatio-temporal perspective, we show that the genus arose during the Pliocene in Europe. Our results also indicate that at least four large-scale dispersal events are required to explain the current distribution of Chiastocheta. Moreover, each dispersal to or from Asia is associated with a host-shift and seems to correspond to an increase in speciation rates. Finally, we highlight the correlation between diversification and climatic fluctuations, which indicate that the cycles of global cooling over the last million years had an influence on the radiation of the group.