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101.
Phylogenetic relationships within the Euro-Mediterranean stock of the Rana temporaria species group (R. temporaria, R. iberica, R. cameranoi, R. macrocnemis, R. holtzi, R. dalmatina, R. graeca, R. latastei) were studied by (1) morphometric analysis, (2) osteological study and (3) electrophoresis. The three data sets were analysed independently and phenograms and cladograms examined for congruent patterns. The tree resulting from electrophoretic analysis is the most clearly resolved (and being also compatible with the other two) is assumed to represent the most likely phylogeny of the Mediterranean brown frogs. Patterns indicated by electrophoretic data matched the molecular clock-hypothesis. This suggests that the first split of the main stock of Mediterranean brown frogs separated ancestors of Rana temporaria and R. iberica from the others during the Late Pleistocene. A second split occurred separating the ancestors of what are currently the other big-bodied and the small-bodied brown frogs. The relationships between and within the three main stocks are discussed in the context of biogeographical and geological data.  相似文献   
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103.
Abstract. In mud-and-thatch houses of Santiago del Estero Province, northwest Argentina, where no insecticides had been sprayed officially to control domestic infestations of the Chagas disease vector Triatoma infestans (Klug) (Hemiptera: Reduviidae), two knockdown (KD) insecticidal collection procedures were compared with the standard flush-out (FO) method for sampling T. infestans. Bugs were collected by FO using 0.2% tetramethrin in bedrooms of (1) 41 houses of Amama village employing 1 man-hour of capture effort per house, and (2) 19 houses of Trinidad and Mercedes villages employing 4 man-hours/house. From the same houses, 2-5 days after the manual FO collection, bugs were collected by KD indoor-spraying of deltamethrin 25mga.i./m2 in Amama, or burning of one γ-HCH (=γ-BHC) fumigant tablet 3.1g of γ-isomer) per bedroom in Trinidad and Mercedes. The majority of infestations were detected by both methods, the proportion of positive houses being 81% at Amama and 95% at the other villages. Although the FO method was more sensitive, at least because it was applied first, the KD method detected infestations in 25% of houses where bugs were not found by FO. Bug densities estimated by FO or by subsequent KD in each house were significantly correlated: r = 0.795 for deltamethrin; r= 0.882 for y-HCH. Compared with FO collections of T.infestans large stages, i.e. adults plus fourth and fifth instar nymphs, the KD catch averaged 0.88x with deltamethrin and 0.57× with γ-HCH, regardless of the apparent population density of bugs per house. However, the KD method has practical advantages of speed and standardization.  相似文献   
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