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In the course of studying the fauna of Coccoidea of China, three new species of Diaspididae were found, they belong to three genera, of which one is new to science, and another two new to China. This paper will be devoted to describing and figuring  相似文献   

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The use of ascoma ontogeny in the systematics of lichenized asco-mycetes is reviewed briefly. Two recently studied examples are discussed to illustrate the use of ontogenetic studies to discover phylogenetic relationships. As one example, theAgyriaceaewas mainly circumscribed by the ascus type and included diverse genera.Xylographais characterized by lirelliform apothecia. However, the ascoma development shares the ontogenetic pattern observed inTrapeliaand its placement in the family was confirmed. In contrast,Anamylopsoraexhibited a substantially different apothecial development and was separated as a family of its own. As a second example, theCandelariaceaeis based on chemical characters. With the detection of pulvinic acid derivatives also in the genusLecanora, the distinction of theCandelariaceaeandLecanoraceaebecame doubtful. Therefore, the ascoma ontogeny was employed to evaluate this classification and is illustrated here in detail forCandelaria fibrosa. The substantial similarity of the ascoma development found in both families suggests that both might be better united. Finally, a general discussion of the significance of ontogenetic characters in lichen taxonomy is included.  相似文献   

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The present paper deals with 3 new "Capritermes typus" termites belonging toMirocapritermes, Procapritermes and Homallotermes respectively. Holotypes, morphotypes,paratypes and thier duplications are deposited in Huanan Tropical Crops College, Tan-hsien, Hainan Is., China.  相似文献   

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Among the graptolites collected by Unit 734 from the Lower Ordovician Qiaotingzi Formation (corresponding to the Ningkou Formation) at Xiayanzhai of Jishou, Hunan, more than ten specimens particularly chosen from the collection were handed over to the writer for. study. These spe cimens preserved as mere carbonaceous films in grey green slate belong to one new genus and the same new species named by the writer Jishougraptus mui gen. et sp. nov. in association with Didymograptus cf. praenuntius  相似文献   

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ABSTRACT

Computers are available that can store, synthesize and replay sounds using digital technology. I describe the major components of audio computers, the principles of digital sound acquisition and playback, and information and caveats for scientists interested in acquiring an audio computer system for their own use. A tutorial on analog filter application is also included as well as a diagnostic procedure and a buyer's check list.  相似文献   

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In this paper, a new genus and species of Noetuidae are reported. Type specimenis kept in the Institute of Zoology, Academia Sinica, Jingia, gen. nov. Proboscis fully developed; palpi obliquely porrect to just beyond frons, the 3rdjoint very short; frons with rounded prominence, with corneous plate below it; eyeslarge, rounded, naked; head and thorax elothed with hairs and few scales; fore tibiae  相似文献   

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Seven species of Kenyentulus have been collected from Yunnan, Xizang(Tibet), Shanxi, Hebei and Henan Provinces since 1973. One of them, K.datongensis was described by Imadate and Yin in 1982, and the other six speciesare summerized as follows: 1. Kenyentulus monlongensis Yin, sp. nov. (Figs. 1-9 ) Total length 1090μ . Head 115 x 83μ;labial palp with 3 setae and a sensilla.Canal of maxillary gland with 2 dilatations along the proximal part,without terminal dilatation. Pseudoculus oval, about 12x 10μ, PR=9.6.  相似文献   

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The ability of populations to undergo adaptive evolution depends on the presence of quantitative genetic variation for ecologically important traits. Although molecular measures are widely used as surrogates for quantitative genetic variation, there is controversy about the strength of the relationship between the two. To resolve this issue, we carried out a meta-analysis based on 71 datasets. The mean correlation between molecular and quantitative measures of genetic variation was weak (r = 0.217). Furthermore, there was no significant relationship between the two measures for life-history traits (r = -0.11) or for the quantitative measure generally considered as the best indicator of adaptive potential, heritability (r = -0.08). Consequently, molecular measures of genetic diversity have only a very limited ability to predict quantitative genetic variability. When information about a population's short-term evolutionary potential or estimates of local adaptation and population divergence are required, quantitative genetic variation should be measured directly.  相似文献   

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In the present paper,two genera and ten species of Acrididae are described as newfrom Yunnan,Kweichow and northern part of Szechwan. All type specimens are deposited in the Department of Biology,Shensi NormalUniversity. Gesonula mundata szemaoensis ssp.nov.(fig.1)  相似文献   

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Freshwater habitats make up only ~0.01% of available aquatic habitat and yet harbor 40% of all fish species, whereas marine habitats comprise >99% of available aquatic habitat and have only 60% of fish species. One possible explanation for this pattern is that diversification rates are higher in freshwater habitats than in marine habitats. We investigated diversification in marine and freshwater lineages in the New World silverside fish clade Menidiinae (Teleostei, Atherinopsidae). Using a time‐calibrated phylogeny and a state‐dependent speciation–extinction framework, we determined the frequency and timing of habitat transitions in Menidiinae and tested for differences in diversification parameters between marine and freshwater lineages. We found that Menidiinae is an ancestrally marine lineage that independently colonized freshwater habitats four times followed by three reversals to the marine environment. Our state‐dependent diversification analyses showed that freshwater lineages have higher speciation and extinction rates than marine lineages. Net diversification rates were higher (but not significant) in freshwater than marine environments. The marine lineage‐through time (LTT) plot shows constant accumulation, suggesting that ecological limits to clade growth have not slowed diversification in marine lineages. Freshwater lineages exhibited an upturn near the recent in their LTT plot, which is consistent with our estimates of high background extinction rates. All sequence data are currently being archived on Genbank and phylogenetic trees archived on Treebase.  相似文献   

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