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31.
SYNOPSIS. Several taxonomic problems arising from recent revisions of the phylum Ciliophora. Initially, electro- and light-microscopic features of 7 species from 4 genera of colpodid ciliates were analyzed by several numerical phenetic procedures. The phenogram derived by using Jaccard's coefficient as the measure of similarity and the unweighted pair-group arithmetic clustering method (UPGMA) yielded a classification with the highest cophenetic correlation coefficient. Subsequently, relationships among 22 oligohymenophoran and related genera were determined by analyzing 57 ultrastructural and light-microscopic features with Jaccard's coefficient and UPGMA. On the basis of these results, the suborder Peniculina is elevated to ordinal rank and the family Turaniellidae is transferred from the Peniculida to the Tetrahymenina. The phenogram also indicated that the nassuline ciliates may be allied with the OLIGOHYMENOPHORA rather than the KINETOFRAGMINOPHORA.  相似文献   
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The bee family Melittidae comprises a small, but biologically fascinating, group of mostly oligolectic bees, some of which are oil collecting. Phylogenetic relationships within this family are poorly understood and some genera cannot be placed with confidence at the subfamily level. We analysed melittid phylogeny using a combined dataset of five nuclear genes [28S, elongation factor‐1α (EF‐1α, F2 copy), long‐wavelength rhodopsin, Na‐K ATPase and RNA polymerase II] spanning 4842 bp plus 68 adult morphological characters. Our study included 25% of the species‐level diversity and 81% of the generic‐level diversity and included all previously recognized tribes and subfamilies. We analysed the dataset using parsimony, maximum likelihood and Bayesian methods. All methods yielded congruent results. All topologies recovered the three previously recognized subfamilies (Dasypodainae, Melittinae, Meganomiinae), but two genera (Afrodasypoda and Promelitta) are transferred from Dasypodainae to Melittinae. On the basis of our tree topologies we identify four tribes (Dasypodaini comb.n. , Hesperapini stat.n. , Macropidini comb.n. and Melittini), only one of which (Melittini) matches a widely used classification. Lastly, we discuss the evolution of host‐plant association in the light of our new phylogenetic hypothesis. Our results strongly support multiple independent origins of oil‐collecting behaviour in the Melittinae.  相似文献   
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When particles of Kashmir bee virus (KBV) and sacbrood virus (SBV) were fed to larvae of the honey bee, Apis mellifera, in Australian colonies, the resulting pupae became in apparently infected. There was no statistically significant difference in the susceptibility of 1, 2, 3 or 4-day-old larvae for either virus, but 5-day-old larvae were significantly less susceptible to SBV than younger larvae. There was no significant difference in the proportions of pupae that became in apparently infected when, as larvae, they were fed various concentrations of each virus, but significantly more larvae were removed from their cells when fed concentrated preparations of each virus than when fed diluted preparations. Susceptible larvae that became in apparently infected with KBV and SBV developed normally into in apparently infected pupae and later, emerged as in apparently infected worker bees.  相似文献   
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A systematic revision of the Malagasy frogs hitherto attributed to the Boophis difficilis group is presented. The difficilis holotype is not conspecific with other specimens hitherto named Boophis difficilis but belongs to the B. tephraeomystax group based on lack of webbing between fingers and the presence of heterogeneously granular ventral skin. Rhacophorus difficilis Boettger, 1892 is considered as junior synonym of Boophis tephraeomystax. The Boophis difficilis group is dissolved and its species are transferred to a new species group named after Boophis majori , the oldest of the included taxa. All species of the B. majori group, their type specimens, and their geographical distributions are revised based on new morphological, bioacoustic and ecological data. Five new species of the group from the eastern rainforests of Madagascar are described. Morphological differentiation within the B. majori group is low, although some species can be distinguished by characters such as snout-vent length, relative tympanum size, or coloration. The most reliable character for species identification are advertisement calls which are strikingly different between most species of the group. Species diversity in Boophis is highest in central eastern Madagascar and gets lower at the northern and southern borders of the island. Available data do not allow a comprehensive phylogenetic analysis of the B. majori group, but a northern subgroup of small species without red coloration and a southern subgroup of larger species with distinct red pigments can be distinguished. Osteological data for B. miniatus are provided. Within Boophis , representatives of all species groups except the B. tephraeomystax group are characterized by a synapomorphic reduction of the anterolateral hyoidal process.  相似文献   
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Despite the obvious benefit of an immune system, its efficacy against pathogens and parasites may show great variation among individuals, populations and species. Understanding the causes of this variation is becoming a central theme in ecology. Many biotic and abiotic factors are known to influence immunocompetence (temperature, age, etc.). However, for a given age, size among individuals varies, probably as a result of accumulated resources. Thus, these variable resources could be allocated to immune defence and, consequently, body size may explain part of the variation in immune responsiveness. However, the influence of body size on immune defence is often overlooked. The present study investigates variations in haemocyte count and phenoloxidase activity in larvae of the phytophagous vine moth Eupoecilia ambiguella Hübner of the same age, although differing in body size. The measurements of immune function are made both when the insects are immunologically naïve and 24 h after a bacterial immune challenge. The base levels of these immune parameters do not covary with body size in naïve larvae. After the bacterial immune challenge, more haemocytes and phenoloxidase enzyme are mobilized, and the mobilization of these immune effectors is correlated positively with individual body size. Thus, larger larvae exhibit higher immunocompetence than smaller ones, suggesting that smaller larvae might be more vulnerable to infection. These results suggest that body size is probably an underestimated variable, which nevertheless modulates the insect immune system and should thus be considered as a covariate in insect immune system measurement. It is recommended therefore, that body size should be taken into account in ecological immunity studies with insects. © 2013 The Royal Entomological Society  相似文献   
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Abstract:  Ostracods are described for the first time from Permian–Triassic shallow marine sediments of the Khuff Formation of central Saudi Arabia. They were collected using a modified acetolysis technique for releasing calcareous shells from limestones that is described herein. Thirty-four species belonging to 17 genera are recognized. Two new species are described: Arqoviella arabica sp. nov. and A. khartamensis sp. nov. The ostracod fauna supports a Late Permian age for the lower Khartam Member and a probable Early Triassic age for the upper Khartam Member of the Khuff Formation of central Saudi Arabia. This suggests that the Permian/Triassic boundary is located within the Khartam Member, rather than at the major lithological break between the Midhnab and Khartam members. Palaeoecological analysis suggests that the palaeoenvironment of the Khuff Formation was shallow marine (between 1 and 50 m deep) on an internal shelf.  相似文献   
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