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The phylogeny of the Forficulina, a suborder of the Dermaptera   总被引:2,自引:0,他引:2  
The phylogeny of the Forficulina (Dermaptera) has been reassessed, examining forty-eight species and thirty characters, of which thirteen characters of the thorax and wings are described or used for phylogenetic purposes for the first time, whereas the remaining seventeen have been extracted from literature. Examination of the thirty characters demonstrates that only twenty-three characters are useful for phylogenetic construction. The characters have been analysed with PAUP 3.1 yielding two equally parsimonious trees. The results suggest an exclusion of the 'Diplatyidae' (themselves paraphyletic) and the Karschiellidae from the Pygidicranidae and support the separation of the Apachyidae from the Labiduridae. A sister-group relationship of Anisolabididae and Spongiphoridae is not supported. The monophyly of the (Spongiphoridae (Forficulidae, Chelisochidae)) is supported.  相似文献   
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The all black carrion crow ( Corvus corone corone ) and the grey and black hooded crow ( Corvus   corone cornix ) meet in a narrow hybrid zone across Europe. To evaluate the degree of genetic differentiation over the hybrid zone, we genotyped crows from the centre and edges of the zone, and from allopatric populations in northern (Scotland–Denmark–Sweden) and southern Europe (western–central northern Italy), at 18 microsatellites and at a plumage candidate gene, the MC1R gene. Allopatric and edge populations were significantly differentiated on microsatellites, and populations were isolated by distance over the hybrid zone in Italy. Single-locus analyses showed that one locus, CmeH9, differentiated populations on different sides of the zone at the same time as showing only weak separation of populations on the same side of the zone. Within the hybrid zone there was no differentiation of phenotypes at CmeH9 or at the set of microsatellites, no excess of heterozygotes among hybrids and low levels of linkage disequilibrium between markers. We did not detect any association between phenotypes and nucleotide variation at MC1R , and the two most common haplotypes occurred in very similar frequencies in carrion and hooded crows. That we found a similar degree of genetic differentiation between allopatric and edge populations irrespectively of their location in relation to the hybrid zone, no differentiation between phenotypes within the hybrid zone, and neither heterozygote excess nor consistent linkage disequilibrium in the hybrid zone, is striking considering that carrion and hooded crows are phenotypically distinct and sometimes recognised as separate species.  相似文献   
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