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41.
Neotropical genera of Cephenniini characterized by an additional leg ‘segment’ (‘trochantellus’) are revised, and the following new taxa are described: Shyri gen.n. , Shyri pichincha sp.n. (type species of Shyri) (Ecuador), Shyri perversus sp.n. (Ecuador), Shyri quitu sp.n. (Ecuador), Shyri microphthalmus sp.n. (Ecuador), Monstrophennium gen.n. (type species: Cephennium spinicolle Schaufuss), Furcodes gen.n. , Furcodes apicalis sp.n. (type species of Furcodes) (Mexico), Furcodes tutule sp.n. (Honduras), Paracephennium pumilio sp.n. (Costa Rica), Pseudocephennium iwokramanum sp.n. (Guyana), Pseudocephennium trilineatum sp.n. (Guyana), Pseudocephennium araguanum sp.n. (Venezuela), Pseudocephennium maximum sp.n. (Venezuela), Pseudocephennium peruvianum sp.n. (Peru), Pseudocephennium cochabambanum sp.n. (Bolivia), Pseudocephennium saramaccanum sp.n. (Suriname) and Pseudocephennium brokopondonum sp.n. (Suriname). Pseudocephennium spinicolle (Schaufuss) is transferred to Monstrophennium. Cladistic analysis of characters from adult morphology of all genera of Cephenniini and a large outgroup sample from Cyrtoscydmini, Eutheiini, Scydmaenini, Clidicini and Mastigini strongly supported the monophyly of Cephenniini. However, only the Cephennomicrus group comprising nine genera was strongly supported as a monophyletic clade, while only weak support was found for the previously suggested Cephennodes group and Cephennium group. Two alternative hypotheses concerning the phylogeny of Cephenniini are put forward and discussed: (i) the Cephennium group is sister to all remaining Cephenniini; or (ii) the Cephennomicrus group is sister to all remaining Cephenniini. The Neotropical genera with ‘trochantellus’ form a well‐supported clade derived from the ancestral lineage of the Cephennodes group.  相似文献   
42.
The aerobic capacity model postulates that high basal metabolic rates (BMR) underlying endothermy evolved as a correlated response to the selection on maximal levels of oxygen consumption () associated with locomotor activity. The recent assimilation capacity model specifically assumes that high BMR evolved as a by‐product of the selection for effective parental care, which required long‐term locomotor activity fuelled by energy assimilated from food. To test both models, we compared metabolic and behavioural correlates in males of laboratory mice divergently selected on body mass‐corrected BMR. elicited by running on the treadmill did not differ between selection lines, which points to the lack of genetic correlation between BMR and . In contrast, there was a positive, genetic correlation between spontaneous long‐term locomotor activity, food intake and BMR. Our results therefore corroborate predictions of the assimilation capacity model of endothermy evolution.  相似文献   
43.
The bot fly Gruninomyia mira Szpila & Pape, gen.n. , sp.n. is described from Iran, North Khorasan, based on a single adult male and with no larval or host data. The monotypic genus shows a mixture of features otherwise found in either the rodent/lagomorph‐parasitizing oestromyine clade (Oestroderma + Oestromyia) or the artiodactyl‐parasitizing hypodermatine clade (Hypoderma + Pallasiomyia + Pavlovskiata + Przhevalskiana + Strobiloestrus) of subfamily Hypodermatinae. A morphology‐based phylogenetic analysis is marginally in favour of a position of Gruninomyia Szpila & Pape, gen.n. as sister taxon of (Oestroderma + Oestromyia). The COI barcode sequence is provided for the new species, and a phylogenetic analysis based on this marker for Oestridae retrieved from GenBank is in agreement with the conclusions based on morphological data. This published work has been registered in ZooBank: http://zoobank.org/urn:lsid:zoobank.org:pub:8F0CBE07‐4E74‐4186‐B690‐2C97D7ED7DA7 .  相似文献   
44.
The circular dichroism (CD) and Fourier transform infrared (FTIR) methods were applied to the conformational studies of alanine-rich peptide Ac-K-[A]11-KGGY-NH2 (where K is lysine, A is alanine, G is glycine and Y is tyrozyne) in water, methanol (MeOH) and trifluoroethanol (TFE). The analysis of CD-spectra of the peptide in water at different concentrations revealed that the secondary structure content depends on the peptide concentration and pH of the solution. The increase of the peptide concentration causes a decrease of alpha-helix content and, simultaneously, an increase of beta-sheet structure, while the unordered structure is the predominant one. Additional elements are discovered in MeOH and TFE but alpha-helix and beta-turns predominate. Moreover, in these solutions the percentage content of the secondary structure does not depend on the temperature. FTIR measurements, carried out at higher peptide concentration (about one order of magnitude) than these CD measurements mentioned above, revealed that in water solution the solid state beta-sheet, and aggregated structures, dominate. However, in TFE the most abundant are alpha-helix and beta-turns structures. The thioflavine T assay showed the tendency of the studied peptide for aggregate.  相似文献   
45.
The monophyly and phylogenetic relationships of the subfamily Microweiseinae were investigated. Twenty‐three in‐group taxa, representing all known genera of Microweiseinae (except for Microcapillata Gordon) were included in a cladistic analysis, based on 45 adult morphological characters. The parsimony analysis of the resulting data matrix supported the monophyly of Microweiseinae, Carinodulini, Serangiini and Microweiseini (inclusive of Sukunahikonini). The recognition of Sukunahikonini renders Microweiseini paraphyletic, and consequently both tribes were synonymized, retaining Microweiseini as a senior family‐group name ( syn.n. ). Genera and tribes of Microweiseinae are diagnosed thoroughly, illustrated and keys to their identification are provided. The following nomenclatural changes were made: Hikonasukuna Sasaji and Orculus Sicard are synonymized with Scymnomorphus Weise ( syn.n. ); Gnathoweisea Gordon is synonymized with Microweisea Cockerell ( syn.n. ); Hikonasukuna monticola Sasaji and Orculus castaneus Sicard are transferred to Scymnomorphus ( comb.n. ); Smilia planiceps Casey, Gnathoweisea hageni Gordon, Gnathoweisea ferox Gordon, Gnathoweisea micula Gordon and Gnathoweisea texana Gordon are transferred to Microweisea ( comb.n ). Three new genera are described: Allenius gen.n. for Allenius californianus sp.n. (type species) from Mexico and Allenius iviei sp.n. from U.S.A.; Gordoneus gen.n. (type species Gnathoweisea schwarzi Gordon from U.S.A.); and Cathedrana gen.n. (type species Cathedrana natalensis sp.n. from South Africa). The first African member of Carinodulini, Carinodulina ruwenzorii sp.n. is described. The genera Microweisea, Coccidophilus, Serangium and Delphastus are well‐known predators of sternorrynchous Hemiptera, such as scale insects (Diaspididae) and whiteflies (Aleyrodidae), and play a significant role in agricultural ecosystems as biocontrol agents. Host data and biological records are summarized for each genus.  相似文献   
46.
1. It has been suggested that chemical information from crowded populations of an animal such as Daphnia carries a cue indicating imminent food limitation, and we suggest that in the presence of fish kairomones, it may also convey a hint of the need to enhance antipredation defences. 2. We performed two‐factorial experiments with Daphnia grown in flow‐through plankton chambers in medium containing high levels of Scenedesmus food plus chemical information on either low or high population density levels and in the presence or absence of fish chemical cues (kairomones) and recorded (i) the effects on Daphnia growth rate and reproduction, and (ii) the effects on Daphnia depth selection. Further depth‐selection experiments were performed to test the reaction of Daphnia to crowding information at different Daphnia concentrations and to test its effect on daytime and night‐time depth selection by different Daphnia instars in the presence of kairomones. 3. The effects of crowding information alone (in the absence of kairomones) were weak and were not significantly strengthened by the addition of kairomones. The effects of kairomones alone (in the absence of crowding information) were much stronger and were increased by the presence of crowding chemicals: Daphnia selected greater depths in daylight (the later the instar and the larger its body size, the greater the depth), their body growth was slower and daily reproductive investment reduced, compared with Daphnia grown in the absence of crowding information. This suggested that crowding chemicals carry a cue indicating the need to invest more into antipredation defences. 4. The adaptive significance of these effects was confirmed by the differential vulnerability to predation of the Daphnia when offered as prey to live roach after being grown for 6 days either in the presence (higher vulnerability) or in the absence (lower vulnerability) of information on high density. 5. The strong interaction between crowding information and fish kairomones may be explained either as the reaction to a cue indicating impending food stress or as the reaction to a signal of increased predation risk. While the former scenario is already known from crowding studies, the latter is a novel idea that stems from the old concept of ‘low‐density anti‐predation refuge’. The two scenarios are not mutually exclusive: each stems from the need to invest in survival rather than in growth and reproduction [Corrections were made to this paragraph after first online publication on 4 April 2012].  相似文献   
47.
A morphological phylogenetic analysis of the tribe Tropiduchini (Hemiptera: Tropiduchidae) is provided for 21 genera among the 26 recognized, including the new genus Oechalinella Wang gen.n. , with a new species Oechalinella bifasciata Wang sp.n. Monophyly of the tribe is well supported by synapomorphies derived from the male genitalia. The strict consensus supports two subclades: ((Montrouzierana + Thymbra) + Thaumantia+) as sister to the clade (Leptovanua + (Vanua + Varma+) + Daradacella+). In the first subclade, the clade (Montrouzierana + Thymbra), distributed in New Caledonia and Papua New Guinea, is well supported by three synapomorphies based on the tegmina, while the Thaumantia+ group is characterized by the conformation of the anal tube and male gonostyli, and distributed from Malesia to Papuasia and in Central Africa. The second subclade is largely distributed from China to Malesia, Papuasia, Southwestern and the Northwestern Pacific islands. The position of the genus Leptovanua remains uncertain. The Varma+ clade is recovered in all analyses. Implied weighting analysis placed the Varma+ lineage as sister to all other genera forming a new group (Leptovanua+ + ((Montrouzierana + Thymbra) + Thaumantia+)). Fennah's definition of Tropiduchini is reviewed according to the phylogenetic results and an identification key to all genera is provided with a referenced synopsis of their distribution. Globally, Tropiduchini exhibits an inter‐tropical latitudinal distribution and a paradoxical bimodal longitudinal distribution pattern in continental Africa, South‐east Asia and the Pacific islands. Distribution data concern nearly 80% of insular taxa. The phylogenetical results suggest that: (i) the tribe originates from continental China; (ii) it evolved mainly from Papuasia by stepping‐stone colonization events, promoting subsequent insular speciation; and (iii) its evolution has mainly been directed by dispersion versus vicariance.  相似文献   
48.
49.
1. Phengaris butterflies are obligatory social parasites of Myrmica ants. Early research suggested that there is a different Myrmica host species for each of the five European Phengaris social parasites, but more recent studies have shown that this was an oversimplification. 2. The pattern of host ant specificity within a Phengaris teleius metapopulation from southern Poland is reported. A combination of studying the frequency distribution of Phengaris occurrence and morphometrics on adult butterflies were used to test whether use of different host species is reflected in larval development. 3. Phengaris teleius larvae were found to survive in colonies of four Myrmica species: M. scabrinodis, M. rubra, M. ruginodis, and M. rugulosa. Myrmica scabrinodis was the most abundant species under the host plant but the percentage of infested nests was similar to other host ant species at two sites and lower in comparison to nests of M. rubra and M. ruginodis at the other two sites. Morphometric measurements of adult butterflies reared by wild colonies of M. scabrinodis and M. ruginodis showed that wing size and number of wing spots were slightly greater for adults eclosing from nests of M. ruginodis. 4. Our results suggest that P. teleius in the populations studied is less specialised than previously suggested. The results are consistent with the hypothesis that P. teleius is expected to be the least specific of the European Phengaris species, as it has the largest and best defended fourth‐instar caterpillars and, as a predatory species, it spends less time in the central larval chambers of the host colonies. The fact that individuals reared by M. ruginodis had wider hind wings may suggest that P. teleius had better access to resources in M. ruginodis than in M. scabrinodis colonies.  相似文献   
50.
This review confronts the classical view of plant immune defence and light acclimation with recently published data. Earlier findings have linked plant immune defences to nucleotide‐binding site leucine‐rich repeat (NBS‐LRR)‐dependent recognition of pathogen effectors and to the role of plasma membrane‐localized NADPH‐dependent oxidoreductase (AtRbohD), reactive oxygen species (ROS) and salicylic acid (SA). However, recent results suggest that plant immune defence also depends on the absorption of excessive light energy and photorespiration. Rapid changes in light intensity and quality often cause the absorption of energy, which is in excess of that required for photosynthesis. Such excessive light energy is considered to be a factor triggering photoinhibition and disturbance in ROS/hormonal homeostasis, which leads to cell death in foliar tissues. We highlight here the tight crosstalk between ROS‐ and SA‐dependent pathways leading to light acclimation, and defence responses leading to pathogen resistance. We also show that LESION SIMULATING DISEASE 1 (LSD1) regulates and integrates these processes. Moreover, we discuss the role of plastid–nucleus signal transduction, photorespiration, photoelectrochemical signalling and ‘light memory’ in the regulation of acclimation and immune defence responses. All of these results suggest that plants have evolved a genetic system that simultaneously regulates systemic acquired resistance (SAR), cell death and systemic acquired acclimation (SAA).  相似文献   
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