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11.
Mantispids (Neuroptera: Mantispidae) are remarkable insects as a result of their close resemblance to the praying mantis (order Mantodea). Although not closely related phylogenetically, as a result of similar selective pressures, both mantispids and mantids have evolved powerful raptorial forelegs for capturing insects. Another striking feature is the hypermetamorphosis in mantispid development, as well as the parasitizing behaviour of the first‐instar larvae. The present review focuses on the role of mantispid vision. First, the morphology and functional significance of the larval eyes (stemmata) are examined. In principle, the stemmata are suitable for spatial vision because of their arrangement and structure. This is then followed by a discussion of how adult mantispids are able to capture fast‐moving insects successfully, although, in contrast to the praying mantis, mantispids rely on superposition eyes rather than on apposition eyes with a frontal region of high acuity. For both larvae and adults, comparisons are made with other insect groups. The present review also addresses the role of mantispid vision as an important cue for triggering mating behaviour; accordingly, sex‐specific differences are considered. Finally, vision in the context of orientation flight is discussed.  相似文献   
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SYNOPSIS. Scanning electron microscopy was used to reveal detailed surface structure of 4 septate ( Gregarina cuneata, G. steini, G. rhyparobiae, Pileocephalus blaberae ) and one aseptate species ( Nematocystis elmassiani ) of eugregarines. The epicyte of all these gregarines is differentiated into a system of regular longitudinal folds. In the septate species these folds undulate so that these organisms glide along. The undulatory pattern is absent from Nematocystis , which does not glide. The theories and the mechanism of gregarine gliding are discussed.  相似文献   
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Abstract A cladistic analysis of morphological characters of the subtribe Xyleborina (Curculionidae, Scolytinae) is presented. An examination of individual characters revealed little phylogenetic information in many characters currently used for delimiting genera. Phylogenetically stable characters were used for the evaluation of the contemporary generic concept. The following genera have been recovered as monophyletic: Cnestus, Dryocoetoides, Eccoptopterus, Xylosandrus, Schedlia, Sampsonius and Taurodemus. The following genera have been found to be polyphyletic: Amasa, Ambrosiodmus, Arixyleborus, Coptoborus, Coptodryas, Cryptoxyleborus, Cyclorhipidion, Euwallacea, Leptoxyleborus, Taphrodasus, Theoborus, Webbia, Xyleborinus and Xyleborus. The analysis permitted the resurrection of four genera: Anisandrus, Microperus, Pseudowebbia and Streptocranus. A number of new combinations at specific level are given: Anisandrus cornutus (Schaufuss, 1891), A. dispar (Fabricius, 1792), A. eggersi (Beeson, 1930), A. improbus (Sampson, 1913), A. longidens (Eggers, 1930), A. maiche Stark, 1936, A. obesus (LeConte, 1868), A. sayi Hopkins, 1915, A. apicalis (Blandford, 1894), A. hirtus (Hagedorn, 1904), Microperus myristicae (Schedl, 1939), M. eucalypticus (Schedl, 1938), M. huangi (Browne, 1983), M. intermedius (Eggers, 1923), M. kadoyamaensis (Murayama, 1934), Pseudowebbia armifer (Schedl, 1942), P. seriata Browne, 1963, P. squamatilis (Schedl, 1955), P. trepanicauda (Eggers, 1923), P. curvatus (Browne, 1986), Streptocranus bicolor Browne, 1949, S. bicuspis (Eggers, 1940), S. capucinulus (Schedl, 1942), S. forficatus (Schedl, 1957), S. fragilis Browne, 1949, S. longicauda Browne, 1960, S. longispinis Browne, 1986, S. mirabilis Schedl, 1939, S. usagaricus (Eggers, 1922), S. sexdentatus (Eggers, 1940). The characters most useful for generic‐level taxonomy of Xyleborina were identified and their states refined and illustrated. An accompanying illustrated multiple‐entry electronic key for the updated xyleborine classification has been published on‐line at www.scolytid.msu.edu .  相似文献   
14.
Recent DNA barcoding of generalist insect herbivores has revealed complexes of cryptic species within named species. We evaluated the species concept for a common generalist moth occurring in New Guinea and Australia, Homona mermerodes, in light of host plant records and mitochondrial cytochrome c oxidase I haplotype diversity. Genetic divergence among H. mermerodes moths feeding on different host tree species was much lower than among several Homona species. Genetic divergence between haplotypes from New Guinea and Australia was also less than interspecific divergence. Whereas molecular species identification methods may reveal cryptic species in some generalist herbivores, these same methods may confirm polyphagy when identical haplotypes are reared from multiple host plant families. A lectotype for the species is designated, and a summarized bibliography and illustrations including male genitalia are provided for the first time.  相似文献   
15.
This short review describes synthetic pores that are made from rigid-rod molecules and can bind oligo-and polymers such as polyacetylenes, p-oligophenyls, terpenoids, polypeptides, polysaccharides, and oligonucleotides. The spotlight is on recent breakthroughs to image the longtime elusive pore-polymer host-guest complexes as single giant pseudorotaxanes.  相似文献   
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Abstract.  1. Bark and ambrosia beetles are crucial for woody biomass decomposition in tropical forests worldwide. Despite that, quantitative data on their host specificity are scarce.
2. Bark and ambrosia beetles (Scolytinae and Platypodinae) were reared from 13 species of tropical trees representing 11 families from all major lineages of dicotyledonous plants. Standardised samples of beetle-infested twigs, branches, trunks, and roots were taken from three individuals of each tree species growing in a lowland tropical rainforest in Papua New Guinea.
3. A total of 81 742 beetles from 74 species were reared, 67 of them identified. Local species richness of bark and ambrosia beetles was estimated at 80–92 species.
4. Ambrosia beetles were broad generalists as 95% of species did not show any preference for a particular host species or clade. Similarity of ambrosia beetle communities from different tree species was not correlated with phylogenetic distances between tree species. Similarity of ambrosia beetle communities from individual conspecific trees was not higher than that from heterospecific trees and different parts of the trees hosted similar ambrosia beetle communities, as only a few species preferred particular tree parts.
5. In contrast, phloeophagous bark beetles showed strict specificity to host plant genus or family. However, this guild was poor in species (12 species) and restricted to only three plant families (Moraceae, Myristicaceae, Sapindaceae).
6. Local diversity of both bark and ambrosia beetles is not driven by the local diversity of trees in tropical forests, since ambrosia beetles display no host specificity and bark beetles are species poor and restricted to a few plant families.  相似文献   
19.
Abstract The ability of the common field grasshopper Chorthippus brunneus to discriminate between different distances under binocular and monocular stimulus conditions is investigated based upon the peering‐jump behaviour. The results show that information obtained from only one eye is sufficient for the grasshopper to determine the jump direction and distance. However, information obtained from both eyes is advantageous for relative distance determination. It is hypothesized that the motion parallax signals from the left and right eye may be summed, thus improving performance. There is no behavioural evidence of a more complex correlation of the information from the two eyes.  相似文献   
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