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We present a cladistic analysis of the subtribe Megalostomina, a Neotropical group of ‘case‐bearer’ leaf beetles. A comparative study of the external and internal adult morphology of Clytrini was undertaken. New characters are described for the subtribe Megalostomina, from the internal sac of aedeagus, which provide a useful phylogenetic signal. More than 180 photographs illustrating the most important characters (74 characters and their respective states) used in the cladistic analysis are provided. The cladistic analysis of 57 terminal taxa and 95 characters was undertaken, under equal weights, and also using implied weights as a means to down‐weight homoplasious characters. We test the monophyly and explore intergeneric relationships of the subtribe Megalostomina, and reconstruct the relationships among the species of Megalostomis Chevrolat. The 42 species recognized can be assigned either to a group mostly containing species of North and Central America, or to a larger one of mostly South American species. Support is low, and the formal naming of groups is deferred pending a revision of all Megalostomina. We confirm the subgenera of Megalostomis of previous classifications are unnatural, and the following changes in the generic classification of the subtribe Megalostomina are proposed: Coleorozena Moldenke syn.n. of Coscinoptera Lacordaire; Coleothorpa Moldenke syn.n. of Coscinoptera Lacordaire; and Euryscopa (Coleoguerina) Moldenke syn.n. of Coscinoptera Lacordaire. Furthermore, six formerly recognized subgenera of Megalostomis are considered junior synonyms of Megalostomis Chevrolat: Megalostomis (Minturnia) Lacordaire syn.n. ; Megalostomis (Heterostomis) Lacordaire syn.n. ; Megalostomis (Scaphigenia) Lacordaire syn.n. ; Megalostomis (Snellingia) Moldenke syn.n. ; Megalostomis (Coleobyersa) Moldenke syn.n. ; and Megalostomis (Pygidiocarina) Moldenke syn.n. Thus, no subgenera are recognized within Megalostomis. Previous hypotheses on Clytrini biogeography were revisited in the light of new biogeographic and phylogenetic knowledge. We hypothesize an origin of Clytrini in tropical/subtropical Gondwana, when South America, Africa, Madagascar and India were connected. Changes in the configuration of the tectonic plates in the Cenozoic allowed the dispersal of Clytrina to the Palaearctic and Nearctic regions, and dispersion of Babiina and Megalostomina through the Nearctic region.  相似文献   
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Apiomerini (Reduviidae: Harpactorinae) collect plant resins with their forelegs and use these sticky substances for prey capture or maternal care. These behaviors have not been described in detail and morphological structures involved in resin gathering, transfer, and storage remain virtually undocumented. We here describe these behaviors in Apiomerus flaviventris and document the involved structures. To place them in a comparative context, we describe and document leg and abdominal structures in 14 additional species of Apiomerini that represent all but one of the 12 recent genera in the tribe. Based on these morphological data in combination with the behavioral observations on A. flaviventris, we infer behavioral and functional hypotheses for the remaining genera within the tribe Apiomerini. Setal abdominal patches for resin storage are associated with maternal care so far only documented for species of Apiomerus. Based on the occurrence of these patches in several other genera, we propose that maternal care is widespread within the tribe. Ventral abdominal glands are widespread within female Apiomerini. We propose that their products may prevent hardening of stored resins thus providing long‐term supply for egg coating. Judging from the diverse setal types and arrangements on the front legs, we predict six different behavioral patterns of resin gathering within the tribe. J. Morphol., 2011. © 2010 Wiley‐Liss, Inc.  相似文献   
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Musk deer (Moschus spp.) are small, solitary forest ruminants well-known for the musk secreted by adult males. Because of illegal hunting and habitat degradation and loss, the five species of musk deer are classified as endangered. Musk deer farming has been a positive example of ex situ conservation, maintaining deer numbers whilst sustaining musk production. This study was conducted at the Xinglongshan Musk Deer Farm in Gansu Province in northwest China, and was designed to explore the relationships among musk extraction, fighting ability and social rank in captive, male alpine musk deer (Moschus sifanicus). Results showed that musk production was related to a male’s rank in the dominance hierarchy. Males in the middle rank of the dominance hierarchy tended to produce more musk than deer of higher and lower ranks. This is due to the time-energy budgeting patterns and captive stress of males with different status in the dominance hierarchy. That is, high-ranking males need to budget more time and energy to maintain their higher rank, while low-ranking males are exposed to more aggression from higher-ranking individuals, thus limiting their access to resources such as food and shelter. Accordingly, high-ranking and low-ranking males endured more stress than middle-ranking males, negatively affecting their annual musk production. Supporting the correlation between musk production and the frequency of tail-rubbing behavior was not significant, average musk extraction could not be predicted based on the frequency of tail-rubbing alone. Status in the dominance hierarchy, however, was positively correlated with tail-rubbing frequency, with males of higher rank tending to tail-rub more frequently. Conflict winners tended to initiate tail-rubbing after the conflict; tail-rubbing accounted for 83.33% of the post-conflict behavior expressed by the winner. Tail-rubbing was one of the behavioral rewards of winning a conflict and was also related to releasing aggression; not solely for scent marking territory and trails. Based on the results of this study, there was no direct relationship between musk production and captive males’ status in the dominance hierarchy (and, therefore, in the intensity of aggression displayed). If the sole aim of musk deer farms is to domesticate musk deer for maximum production of musk, we suggest that highly aggressive males be removed from the population. Musk production will remain unchanged, however, aggression level and intensity of fighting could be lessened thus reducing farming costs.  相似文献   
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Integrating phylogenetic data into macroecological studies of biodiversity patterns may complement the information provided by present‐day spatial patterns. In the present study, we used range map data for all Geonoma (Arecaceae) species to assess whether Geonoma species composition forms spatially coherent floristic clusters. We then evaluated the extent to which the spatial variation in species composition reflects present‐day environmental variation vs. nonenvironmental spatial effects, as expected if the pattern reflects historical biogeography. We also examined the degree of geographic structure in the Geonoma phylogeny. Finally, we used a dated phylogeny to assess whether species richness within the floristic clusters was constrained by a specific historical biogeographic driver, namely time‐for‐diversification. A cluster analysis identified six spatially coherent floristic clusters, four of which were used to reveal a significant geographic phylogenetic structure. Variation partitioning analysis showed that 56 percent of the variation in species composition could be explained by spatial variables alone, consistent with historical factors having played a major role in generating the Geonoma diversity pattern. To test for a time‐for‐diversification effect, we correlated four different species richness measures with the diversification time of the earliest large lineage that is characteristic of each cluster. In support of this hypothesis, we found that geographic areas with higher richness contained older radiations. We conclude that current geographic diversity patterns in Geonoma reflect the present‐day climate, but to a larger extent are related to nonenvironmental spatial constraints linked to colonization time, dispersal limitation, and geological history, followed by within‐area evolutionary diversification. Abstract in Spanish is available at http://www.blackwell‐synergy.com/loi/btp .  相似文献   
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