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21.

Background

In the mega-diverse insect order Lepidoptera (butterflies and moths; 165,000 described species), deeper relationships are little understood within the clade Ditrysia, to which 98% of the species belong. To begin addressing this problem, we tested the ability of five protein-coding nuclear genes (6.7 kb total), and character subsets therein, to resolve relationships among 123 species representing 27 (of 33) superfamilies and 55 (of 100) families of Ditrysia under maximum likelihood analysis.

Results

Our trees show broad concordance with previous morphological hypotheses of ditrysian phylogeny, although most relationships among superfamilies are weakly supported. There are also notable surprises, such as a consistently closer relationship of Pyraloidea than of butterflies to most Macrolepidoptera. Monophyly is significantly rejected by one or more character sets for the putative clades Macrolepidoptera as currently defined (P < 0.05) and Macrolepidoptera excluding Noctuoidea and Bombycoidea sensu lato (P ≤ 0.005), and nearly so for the superfamily Drepanoidea as currently defined (P < 0.08). Superfamilies are typically recovered or nearly so, but usually without strong support. Relationships within superfamilies and families, however, are often robustly resolved. We provide some of the first strong molecular evidence on deeper splits within Pyraloidea, Tortricoidea, Geometroidea, Noctuoidea and others. Separate analyses of mostly synonymous versus non-synonymous character sets revealed notable differences (though not strong conflict), including a marked influence of compositional heterogeneity on apparent signal in the third codon position (nt3). As available model partitioning methods cannot correct for this variation, we assessed overall phylogeny resolution through separate examination of trees from each character set. Exploration of "tree space" with GARLI, using grid computing, showed that hundreds of searches are typically needed to find the best-feasible phylogeny estimate for these data.

Conclusion

Our results (a) corroborate the broad outlines of the current working phylogenetic hypothesis for Ditrysia, (b) demonstrate that some prominent features of that hypothesis, including the position of the butterflies, need revision, and (c) resolve the majority of family and subfamily relationships within superfamilies as thus far sampled. Much further gene and taxon sampling will be needed, however, to strongly resolve individual deeper nodes.  相似文献   
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A microsatellite‐enriched library of Job's tears (Coix lacryma‐jobi L. var. Ma‐yuen Stapf) was constructed using a modified biotin–streptavidin capture method. After screening, 17 polymorphic microsatellites were used for diversity analysis among 30 Job's tears accessions. The number of alleles ranged from one to five alleles per locus with an average of 2.8 alleles. Expected heterozygosity (HE) and polymorphism information content (PIC) ranged from 0 to 0.676 and from 0 to 0.666, respectively. The newly developed microsatellite markers are expected to be very valuable tools for evaluation of genetic diversity among large germplasm collection of Job's tears present in our Korean Gene Bank.  相似文献   
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The purpose of this preliminary study was to test the hypothesis that subsyndromal depression is associated with the volume of medial prefrontal regional gray matter and that of white matter lesions (WMLs) in the brains of cognitively normal older people. We also explored the relationships between subsyndromal depression and medial prefrontal regional gray matter volume, limbic regional gray matter volume, and lobar WMLs in the brains of patients with mild cognitive impairment (MCI) and Alzheimer''s disease (AD). We performed a cross-sectional study comparing patients with subsyndromal depression and nondepressed controls with normal cognition (n = 59), MCI (n = 27), and AD (n = 27), adjusting for sex, age, years of education, and results of the Mini-Mental State Examination. Frontal WML volume was greater, and right medial orbitofrontal cortical volume was smaller in cognitively normal participants with subsyndromal depression than in those without subsyndromal depression. No volume differences were observed in medial prefrontal, limbic, or WML volumes according to the presence of subsyndromal depression in cognitively impaired patients. The absence of these changes in patients with MCI and AD suggests that brain changes associated with AD pathology may override the changes associated with subsyndromal depression.  相似文献   
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Six species of insect endoparasitoids were identified from Elcysma westwoodii, which is the most damaging lepidopteran pest of Prunus yedoensis. From Hymenoptera, two species were identified: a species in Braconidae and Charops striatus in Ichneumonidae. From Diptera, there were four species in Tachinidae: Compsilura concinnata, Exorista sp., Pales sp. and Tachinidae spp. The parasitic ratio was 4.86% (45 of 926 larvae). The hymenopterans were parasitic on 31 individuals of E. westwoodii (68.9%) and the dipterans were parasitic on 14 individuals (31.1%). It was found that parasitoids from the larvae of E. westwoodii were all either endoparasitoids or larval parasitoids. However, Exorista sp. of Tachinidae was found to be either a larval parasitoid or larval-pupal parasitoid. Additionally, all the identified parasitoids were solitary parasitoids, as only one parasite occurred in a larva of E. westwoodii. Because the larva of E. westwoodii eats and molts after it is parasitized, all the parasitoids were identified as koinobionts. There were no big differences in morphological characteristics and life histories between C. striatus and C. concinnata. However, for Exorista sp. and Pales sp., males took 3–5 days longer to emerge from their pupae and had remarkably longer body lengths than females.  相似文献   
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A taxonomic review of the genus Gonioctena in the Korean Peninsula is presented. Ten species belonging to three subgenera are recognized. Gonioctena jacobsoni (Ogloblin et Medvedev) and Gonioctnea kamiyai Kimoto are recorded for the first time in Korea. A key, illustrations of diagnostic characters, and the coloration patterns of Korean Gonioctena are provided.  相似文献   
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Two aleocharine species, Autalia rivularis (Gravenhorst) and Brachida clara (Weise), are identified for the first time in Korea. Diagnoses, habitus illustrations, and line drawings of diagnostic characters are provided.  相似文献   
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