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91.
The Napaeus variatus (Webb & Berthelot, 1833) species group from the Canary Islands is reviewed from literature information, types, other museum specimens, and newly collected material. Anatomy data is newly provided for six species. Five new species are described: N. elegans and N. esbeltus from Tenerife, N. orientalis and N. beguirae from La Gomera, and N. exilis from Gran Canaria. Eight species lack a diverticulum and are referred to the subgenus Napaeus (Napaeus) Albers, 1850, whereas five species are provided with a diverticulum and arc referred to Napaeus (Napaeinus) Hesse, 1933. Four species cannot be assigned to a subgenus due to a lack of information. Keys of species from the different islands are provided.  相似文献   
92.
The new species Ceratozamia vovidesii from a Pleistocene floristic refuge in southern Mexico is described and illustrated. It show an affinity with C. matudae Lundell and C. mirandae Vovides, Pérez-Farrera & Iglesias from Chiapas, but it differs from them in leaf, male and female cones, and trunk morphology.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 393–400.  相似文献   
93.
A new species of Holcus L. (Poaceae), endemic to the Azores archipelago (Portugal), is described. The vegetative and reproductive structures were studied. The diagnostic characters were compared with those of closely related species. New chromosome counts in Holcus azoricus M. Seq. & Castrov. (2 n  = 35) and H. rigidus Hochst. (2 n  = 28) are included. A possible hybrid origin is hypothesized; the potential parents are H. lanatus L. and H. rigidus .  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 259–267.  相似文献   
94.
With this paper we initiate a taxonomic review of the genusNapaeus from the Canary Islands, indicating the statisticalmethodology used therein. We discuss the taxonomic problem ofNapaeus (Napaeinus) nanodes (Shuttleworth, 1852), designateits lectotype and describe five new species: Napaeus (Napaeinus)doliolum Henríquez, Napaeus (Napaeinus) bechi Alonso& Ibáñez, Napaeus (Napaeus) taguluchensisHenríquez, Napaeus (Napaeus) pygmaeus Ibáñez& Alonso and Napaeus (Napaeus) tagamichensis Henríquez,the first two from Tenerife; and the other three from La Gomera.Furthermore, we discuss the general relationships of the genusand its two sub-genera, whose original diagnoses are deficient;because of this, we think that in the future a broad reviewof the subfamily Eninae will be necessary in order to clarifythe actual position of this subfamily in the Canary Islands. (Received 11 March 1991; accepted 22 September 1992)  相似文献   
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Plant virus diseases constitute one of the limiting factors to the productivity of agriculture. Changes in host plants and insect vector populations that might result from climate change (their geographical distribution range, their densities, migration potential and phenology) could affect the spread of plant viruses. At the individual level, alterations in plant physiological processes that are relevant to their molecular interactions with viruses, like changes in metabolism, leaf temperature, and their effects on some processes, like the temperature-sensitive antiviral resistance based in RNA silencing, can also influence the ability of individual plants to control viral infections. In order to assess the impact that climate change may have on the incidence and spread of hemipteran-borne plant viruses, its potential effects on virus/plant interactions and hemipteran insect vectors, as well as other operating processes, which could exacerbate or mitigate them, are identified and analyzed in this review.  相似文献   
98.
Accelerating taxonomic knowledge and making accurate species identifications are critically important given the current biodiversity crisis, particularly in biodiversity hotspots such as Mesoamerica. Objective species delimitation that reduces investigator‐driven bias is fundamental to the establishment of appropriate conservation strategies, above all in managed species. Previous morphological and molecular studies on three managed stingless bee species of the genus Scaptotrigona distributed in Mexico (S. mexicana, S. pectoralis and S. hellwegeri) suggested that both S. mexicana and S. hellwegeri are cryptic species complexes. Herein we tested species delimitation by analysing sequence information of five markers (two mitochondrial: cox1 and 16S, and three nuclear: ITS1, EF1‐α, ArgK) within a Bayesian coalescent framework to test the putative species. We obtained two different hypotheses using a Generalized Mixed Yule Coalescent (GMYC) model: four (cox1) and six (16S) species. After the species validation step with the Bayesian species‐delimitation analysis (BPP), we suggest that only S. mexicana is a complex of two species with different distribution (along the Pacific and the Atlantic coasts, respectively). We highly recommend avoiding colony exchange between geographical regions in order to conserve the genetic integrity of both taxa.  相似文献   
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Thirteen juvenile Golden Eagles Aquila chrysaetos were tracked during their first year of life using satellite telemetry. Distances to the nest attained during that period and the age at the onset of juvenile dispersal were explored. The performance of nine different criteria to determine that age was analysed. In general, after a brief period of restricted movements around the nest, the average distance to the nest increased with time. Maximum distances to the nest ranged between 57.7 and 184.3 km, and were considerably greater in females (mean ± sd, 138.5 ± 44.5 km) than in males (70.5 ± 14.0 km). No sex difference was observed in the age at which that distance was attained (males: 329 ± 32 days, females: 312 ± 20 days). The onset of juvenile dispersal took place around the fifth month of life (September in Spain). Eight of the nine criteria provided similar results, suggesting that in Spain dispersal starts when birds are between 140 and 180 days old, and that the post-nestling period lasts between 60 and 120 days. For future studies, to determine the age at which the onset of juvenile dispersal occurs, we recommend the use of either the first day on which individuals were located beyond the mean distance between nests of different pairs (10 km in our study area), or the date of the record midway between the first and the last location recorded during the month in which the maximum variability in the distance to the nest was observed.  相似文献   
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