首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   31篇
  免费   1篇
  2023年   1篇
  2015年   1篇
  2014年   2篇
  2013年   2篇
  2012年   3篇
  2011年   2篇
  2010年   3篇
  2009年   1篇
  2008年   1篇
  2007年   1篇
  2006年   1篇
  2005年   2篇
  2004年   2篇
  2001年   1篇
  2000年   1篇
  1999年   1篇
  1998年   1篇
  1997年   1篇
  1996年   1篇
  1994年   1篇
  1992年   1篇
  1989年   1篇
  1979年   1篇
排序方式: 共有32条查询结果,搜索用时 16 毫秒
1.
The genus Etiennea Matile‐Ferrero is synonymized with Hemilecanium Newstead (Hemiptera: Coccidae). We base this decision on a morphological comparative study of adult females, adult males and first‐instar nymphs (crawlers), including a phylogenetic analysis. We recovered a sister group relationship between the type species of the two genera, Etiennea villiersi Matile‐Ferrero and Hemilecanium theobromae Newstead; that is, each was more closely related to the other than either was to other species in their respective genera. All species hitherto included in Etiennea are transferred to Hemilecanium: H. bursera (Hodgson & Kondo) comb. nov., H. cacao (Hodgson) comb. nov., H. candelabra (Hodgson) comb. nov., H. capensis (Hodgson) comb. nov., H. carpenteri (Newstead) comb. nov., H. cephalomeatus (Hodgson) comb. nov., H. combreti (Hodgson) comb. nov., H. ferina (De Lotto) comb. nov., H. ferox (Newstead) comb. nov., H. gouligouli (Hodgson) comb. nov., H. halli (Hodgson) comb. nov., H. kellyi (Brain) comb. nov., H. madagascariensis (Hodgson) comb. nov., H. montrichardiae (Newstead) comb. nov., H. multituberculum (Hodgson) comb. nov., H. petasus (Hodgson) comb. nov., H. sinetuberculum (Hodgson) comb. nov., H. tafoensis (Hodgson) comb. nov., H. ulcusculum (Hodgson) comb. nov., and H. villiersi (Matile‐Ferrero) comb. nov. Keys to the adult females of all 26 species and known adult males and first‐instar nymphs are provided. The adult males and first‐instar nymphs of H. theobromae Newstead and E. villiersi Matile‐Ferrero are for the first time fully described and illustrated. One new potential pest species of Hemilecanium, H. uesatoi Kondo & Hardy sp. nov., which was collected on three islands of the Ryukyu Archipelago, Japan, is described and illustrated based on the adult female, adult male and first‐instar nymph. We discuss evidence that H. uesatoi is a new introduction to the Ryukyu Archipelago. The first‐instar nymphs of Hemilecanium can be divided into two distinct morphological groups, the petasus group and the theobromae group.  相似文献   
2.
We provide a general overview of features and technical specifications of an online, interactive tool for the identification of scale insects of concern to the U.S.A. ports-of-entry. Full lists of terminal taxa included in the keys (of which there are four), a list of features used in them, and a discussion of the structure of the tool are provided. We also briefly discuss the advantages of interactive keys for the identification of potential scale insect pests. The interactive key is freely accessible on http://idtools.org/id/scales/index.php  相似文献   
3.
It is now clear that mechanisms of sex determination are extraordinarily labile, with considerable variation across all taxonomic levels. This variation is often expressed through differences in the genetic system (XX‐XY, XX‐XO, haplodiploidy, and so on). Why there is so much variation in such a seemingly fundamental process has attracted much attention, with recent ideas concentrating on the possible role of genomic conflicts of interest. Here we consider the role of inter‐ and intra‐genomic conflicts in one large insect taxon: the scale insects. Scale insects exhibit a dizzying array of genetic systems, and their biology promotes conflicts of interest over transmission and sex ratio between male‐ and female‐expressed genes, parental‐ and offspring‐expressed genes (both examples of intra‐genomic conflict) and between scale insects and their endosymbionts (inter‐genomic conflict). We first review the wide range of genetic systems found in scale insects and the possible evolutionary transitions between them. We then outline the theoretical opportunities for genomic conflicts in this group and how these might influence sex determination and sex ratio. We then consider the evidence for these conflicts in the evolution of sex determination in scale insects. Importantly, the evolution of novel genetic systems in scale insects has itself helped create new conflicts of interest, for instance over sex ratio. As a result, a major obstacle to our understanding of the role of conflict in the evolution of sex‐determination and genetic systems will be the difficulty in identifying the direction of causal relationships. We conclude by outlining possible experimental and comparative approaches to test more effectively how important genomic conflicts have been.  相似文献   
4.
5.
Fang Wang  Ji-Nian Feng 《ZooKeys》2012,(244):59-65
A new species of soft scale, Coccus multisetus Wang & Feng, sp. n. is described and illustrated from Yunnan, China. A key to adult females of all Coccusknown from China is provided.  相似文献   
6.
A jack of all trades can be master of none—this intuitive idea underlies most theoretical models of host‐use evolution in plant‐feeding insects, yet empirical support for trade‐offs in performance on distinct host plants is weak. Trade‐offs may influence the long‐term evolution of host use while being difficult to detect in extant populations, but host‐use evolution may also be driven by adaptations for generalism. Here we used host‐use data from insect collection records to parameterize a phylogenetic model of host‐use evolution in armored scale insects, a large family of plant‐feeding insects with a simple, pathogen‐like life history. We found that a model incorporating positive correlations between evolutionary changes in host performance best fit the observed patterns of diaspidid presence and absence on nearly all focal host taxa, suggesting that adaptations to particular hosts also enhance performance on other hosts. In contrast to the widely invoked trade‐off model, we advocate a “toolbox” model of host‐use evolution in which armored scale insects accumulate a set of independent genetic tools, each of which is under selection for a single function but may be useful on multiple hosts.  相似文献   
7.
蚧虫蜡泌物的化学研究进展   总被引:7,自引:0,他引:7  
总结了国内外对蚧虫蜡泌物及其化学成分的研究进展 ,内容包括蜡泌物形成介壳的主要类型 ;蜡泌物的化学研究方法及已涉及的种类 ;蜡泌物的主要化学组成 ,并对 5类物质 ,即蜡、烃类、树脂或萜类、色素类、内蜜露作了重点叙述。最后 ,讨论了研究蚧虫蜡泌物的化学成分具有的意义和应用前景 ,包括蜡泌物作为生物资源的利用 ;以蚧虫作为农林、果树和花卉业的重要害虫 ,针对蜡泌物的特点研制相应的新型杀虫剂 ;利用蜡泌物的化学信息素对天敌的诱导作用 ,开展蚧虫生物防治 ;利用蜡泌物作为化学分类性状的应用等。  相似文献   
8.
Babul scale Anomalococcus indicus Ramakrishna Ayyar, a major pest of Vachellia nilotica (L.f.) P.J.H. Hurter & Mabb. on the Indian subcontinent, has been identified as a potential biocontrol agent for prickly acacia V. nilotica subsp. indica (Benth.) Kyal. & Boatwr. in Australia and was imported from southern India for detailed assessment. The life history of A. indicus under controlled glasshouse conditions was determined as a part of this assessment. Consistent with other scale species, A. indicus has a distinct sexual dimorphism which becomes apparent during the second instar. Females have three instars, developing into sexually mature nymphs after 52 days. The generation time from egg to egg was 89 days. Females are ovoviviparous, ovipositing mature eggs into a cavity underneath their body. An average of 802 ± 114 offspring were produced per female. Reproductive output was closely associated with female size; larger females produced more than 1200 offspring. Crawlers emerged from beneath the female after an indeterminate period of inactivity. They have the only life stage at which A. indicus can disperse, though the majority settle close to their parent female forming aggregative distributions. In the absence of food, most crawlers died within three days. Males took 62 days to develop through five instars. Unlike females, males underwent complete metamorphosis. Adult males were small and winged, and lived for less than a day. Parthenogenesis was not observed in females excluded from males. The life history of A. indicus allows it to complement other biological control agents already established on prickly acacia in Australia.  相似文献   
9.
The genus Xenolecanium Takahashi is reviewed and transferred from the subfamily Myzolecaniinae to the Coccinae (tribe Paralecaniini). The type species Xenolecanium mangiferae Takahashi is redescribed, and Xenolecanium takahashii Kondo sp. nov. from Indonesia is described based on the adult female and first instar nymph. A taxonomic key is provided to separate adult females of the two species of Xenolecanium. Xenolecanium rotundum Takahashi is transferred to become the type species of a new monotypic genus, Takahashilecanium Kondo, which is also placed in the Paralecaniini. The morphological justification for placing Xenolecanium and Takahashilecanium in the Paralecaniini is discussed, and we provide a taxonomic key for separating both genera from all other members of the Paralecaniini.  相似文献   
10.
The Pseudomyrmex viduus group is a Neotropical clade of arboreal ants containing 13 species, of which three are newly described here: P. insuavis, P. ultrix, and P. vitabilis. Most species inhabit the domatia of specialized ant-plants. The ants keep brood and scale insects (Coccoidea) in the plant cavities, and defend their nest sites much more aggressively than do generalist species of Pseudomyrmex nesting in dead twigs. Five species are obligate associates of trees in the genus Triplaris (Polygonaceae) and five taxa are restricted to Tachigali (Fabaceae: Caesalpinioideae). One species, P. viduus (F. Smith), is much less host-specific, inhabiting Cordia, Coussapoa, Ocotea, Pseudobombax, Pterocarpus, Sapium, Triplaris and other myrmecophytes. Nothing is known about the biology of P. vitabilis, a close relative of/?viduus. The last member of the species group, P. kuenckeli (Emery), is a non-specialist but aggressive species that nests in dead branches of various plants. A cladistic analysis indicates that this aggressive behaviour evolved before obligate associations with specialized ant-plants, and that the Triplaris and Tachigali inhabitants each form their own clade. P. viduus, which is nested within the Triplaris-associated clade, suggests a possible model for host plant evolution in these ants wherein shifts from one ant-plant to another involve an intermediate phase of expanded host plant use. At least nine other Pseudomyrmex species, from two different species groups (not closely related to the P. viduus group), have evolved specialized associations with Triplaris or Tachigali including five new species: P. crudelis, P. deminutus, P. eculeus. P. ferox and P. hospitalis. Although the P. viduus group is centred in the Amazon basin, the geographic ranges of most species do not coincide with the Pleistocene forest refugia proposed by Haffer and others. A consideration of the phylogenetic relationships, distribution patterns, and host plant specificity of the ants indicates that much of the diversification of the P. viduus group occurred before the Pleistocene, and that the interactions with Triplaris and Tachigali plants are also of Tertiary origin.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号