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251.
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The Gelechioidea (>18 000 species), one of the largest superfamilies of Lepidoptera, are a major element of terrestrial ecosystems and include important pests and biological model species. Despite much recent progress, our understanding of the classification, phylogeny and evolution of Gelechioidea remains limited. Building on recent molecular studies of this superfamily and a recently revised family/subfamily classification, we provide an independent estimate of among‐family relationships, with little overlap in gene sample. We analysed up to five nuclear genes, totalling 6633 bp, for each of 77 gelechioids, plus up to 14 additional genes, for a total of 14 826 bp, in 45 of those taxa and all 19 outgroup taxa. Our maximum‐likelihood (ML) analyses, like those of previous authors, strongly support monophyly for most multiply‐sampled families and subfamilies, but very weakly support most relationships above the family level. Our tree looks superficially divergent from that of the most recent molecular study of gelechioids, but when the previous tree is re‐rooted to accord maximally with ours, the two phylogenies agree entirely on the deepest‐level divergences in Gelechioidea, and strongly though incompletely on among‐family relationships within the major groups. This concordance between independent studies is evidence that the groupings (or at least the unrooted branching order) are probably accurate, despite the low bootstrap values. After re‐rooting, both trees divide the families into three monophyletic groups: a ‘Gelechiid Assemblage,’ consisting of Gelechiidae and Cosmopterigidae; a ‘Scythridid Assemblage,’ consisting of Stathmopodidae, Scythrididae, Blastobasidae, Elachistidae, Momphidae, Coleophoridae and Batrachedridae; and a ‘Depressariid Assemblage,’ consisting of Autostichidae, Xyloryctidae, Lecithoceridae, Oecophoridae, Depressariidae and Lypusidae. Within the largest family, Gelechiidae, our results strongly support the pairing of Anomologinae with Gelechiinae, in accordance with a recent study of this family. Relationships among the other subfamilies, however, conflict moderately to strongly between studies, leaving the intrafamily phylogeny unsettled. Within the ‘Scythridid Assemblage,’ both trees support an ‘SSB clade’ consisting of Blastobasidae + (Scythrididae + Stathmopodidae), strongly resolved only in our results. Coleophoridae + Batrachedridae is supported, albeit weakly, in both trees, and only Momphidae differ in position between studies. Within the ‘Depressariid Assemblage,’ both trees support an ‘AXLO’ clade consisting of Autostichidae, Xyloryctidae, Lecithoceridae and Oecophoridae. The monophyly of this clade and relationships therein are supported weakly in previous results but strongly in ours. The recently re‐defined family Depressariidae is paraphyletic in our tree, but the evidence against depressariid monophyly is very weak. There is moderate support for a core group of Depressariidae consisting, among the seven subfamilies we sampled, of Depressariinae, Aeolanthinae and Hypertrophinae. We show that gelechioids have a higher total number and percentage of species that are saprophagous as larvae than any other apoditrysian superfamily, that saprophagy is concentrated primarily in the ‘AXLO clade,’ and that the ancestral gelechioid condition was probably feeding on live plants. Among the living‐plant feeders, concealed external feeding was probably the ancestral state. The multiple origins of internal feeding of various kinds, including leaf mining (otherwise almost unknown in Apoditrysia), are restricted mostly to the Scythridid and Gelechiid Assemblages. The traits that predispose or permit lineages to adopt these unusual life histories are worthy of study.  相似文献   
253.
Etiolated pea plants, grown aseptically, were treated with eitherring- or carboxyl-labelled indole-3-acetic acid (IAA), and subsequentlythe carbon dioxide which had been released, the residual culturesolution, and the dissected plant parts were examined for radioactivecompounds. Although some breakdown of IAA was detected in theabsence of plants, much more decarboxylation occurred when theywere present. The only metabolite found in any quantity in vivowas IAA-aspartate. Very small amounts of indole-3-aldehyde,and of other substances identified only tentatively, were alsoobserved. A further substance, possibly N-hydroxy indole-3-aceticacid, was found in the seedlings as well as in the culture medium;its presence in vivo is unlikely to have any metabolic significance.The paucity of products in the seedlings suggests that rapidbreakdown of IAA does not occur in vivo.  相似文献   
254.
Some simple indications of the presence of pressure in hyphaltips have been used to investigate osmotic relationships. Theseare (1) cytoplasmic flow due to pressure loss through the apexcaused by janus green solutions, (2) extrusion of cell contentson damaging the cell wall with dilute acetic acid, and (3) continuationof apical extension growth. The osmotic equivalent of growingtips is considerably in excess of that of the growth medium,resulting in the presence of a hydrostatic pressure differentialbetween the interior of the tip and its environment. Normalextension growth is dependent upon this differential. Hyphaltips are able rapidly to equilibrate osmotically to appliedhyper- and hypotonic solutions so as to re-establish a pressuredifferential consistent with the rate of synthesis of wall materialat the apex. Apices that are caused to cease extension growthby applied hypertonic solutions enter upon a sequence of slightbut significant morphological changes leading to progressiveocclusion of the apex by continued formation of wall substancein the absence of a sufficiently high pressure differential.The subsequent behaviour of such apices depends upon the stagein this sequence reached at the re-establishment of a pressuredifferential sufficient for extension growth.  相似文献   
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A new species, Desoria mulyeongariensis, shares some characters with D. choi (Lee), such as the number of setae on retinaculum and apical setae on manubrium. However, it could be easily distinguished from D. choi by the number of ommatidia. This species is also well characterized by having long and thickened smooth macrosetae on the body, and 6 basomedian setae on labium.  相似文献   
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The susceptibility of members of the Anopheles sinensis Group in Korea to insecticides was evaluated under laboratory conditions using 15 insecticides currently used by local public health centers in Korea. The insecticides included eight pyrethroids, six organophosphates and a pyrazol analogue. Based on their LC50 values, the order of susceptibility of An. sinensis larvae to the insecticides was bifenthrin, chlorfenapyr, α-cypermethrin and λ-cyhalothrin, with values of 0.009, 0.04, 0.06 and 0.08 p.p.m., respectively. The least susceptibility was obtained with fenitrothion, with an LC50 of 7.7 p.p.m. In the comparative resistance test, the resistance ratios (RR) of 14 insecticides were compared to each other using two strains of members of the An. sinensis Group collected in the locality in 2001 and 2008. Anopheles spp. demonstrated higher RR to organophosphates such as fenthion, and low RR for the pyrethroids. Among the organophosphates, fenthion had the highest RR of 33.3 and 270.0 fold differences for LC50 and LC90 values, respectively. Among the pyrethroids, permethrin was observed to have the highest RR of 3.8 and 1.8 fold differences for LC50 and LC90 values, respectively. However, there were no significant differences in susceptibility to chlorfenapyr, chlorpyrifos, deltamethrin and fenitrothion. An. sinensis s. l. was more susceptible to the six insecticides bifenthrin, λ-cyhalothrin, α-cypermethrin, cypermethrin, cyfluthrin and pyridafenthion, showing 0.03, 0.06, 0.3, 0.3, 0.4 and 0.4 fold differences in resistance rates (RR LC50), respectively.  相似文献   
260.
The genus Byctiscus reported in Korea in five of nine species (B. lacunipennis, B. rugosus, B. puberulus puberulus, B. princeps and B. coerulans) is described for the last instar larvae. In addition, the cradle structure and host‐plants are provided.  相似文献   
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