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1.
Abstract. The new World genus Acrolophus , with about 225 species, has alreay twenty-six generic synonyms. a further four genera, Daulia Walker, 1863 [norm. praeocc., nec Walker, 1859] (monobasic), Brachysymbola Meyrick (monobasic), Orothyntis Meyrick (two species) and Psephocrita Meyrick (monobasic) are here synonmized with Acrolophus. Daulia indecora Walker, Brachysymbola sepulcralis Meyrick, Orothyntis scruopulata Meyrick, O.torata meyrick and Psephocrita melanodoxa Meyrick are transferred to Acrolophus. Acrolophus reflexa (Fabricius) and its genitalia are figured from recently collected materila.  相似文献   

2.
Lygus hesperus Knight is native to the western United States and is a perennial pest of numerous crops in California. It is responsible for triggering the early season application of insecticides on cotton, Gossypium hirsutum L., and strawberries, Fragaria L. Despite several surveys conducted in alfalfa (Medicago sativa L.) grown in central California, nymphal parasitoids associated with L. hesperus and L. elisus have not been found. Two exotic parasitoids were released into California beginning in 1998. Peristenus relictus (Ruhte), formerly P. stygicus Loan, and P. digoneutis Loan were collected from several locations in southern Europe and released at up to six locations over a 6-year period. At the original release site in Sacramento, a 0.25-ha plot of alfalfa, parasitism by P. digoneutis and P. relictus combined increased from zero to 90%, 3 years after the last releases were made. Parasitoids have been recovered from vacant fields of weedy annuals within 2 km of this site. Recoveries at more southerly release sites in central California have been poor.  相似文献   

3.
The effect of sand-dollar Mellita quinquiesperforata (Leske) burrowing on a soft-bottom meiofauna community was examined at a subtidal site located off the northwest Florida coast. M. quinquiesperforata were common at the site with an average of 3 ind · 0.25 m −2 and their burrow trails were a distinctive feature of the sediment surface. At the site, sand dollars disrupted ≈ 14% of the sediment surface · h−1. Sand-dollar burrowing did not decrease total meiofauna abundances significantly (P > 0.05); however, the abundances of one harpacticoid species, Halectinosoma sp., foraminifera and mites were significantly lower (P < 0.05) in samples collected from a burrow trail than in samples collected in front of the sand dollar. The lower abundances of Halectinosoma sp. and mites in the burrow trail were probably due to sediment disturbance. The lower abundances of foraminifera in the burrow trails were probably due to sand-dollar predation. In contrast to studies in intertidal areas, total nematode abundances were significantly higher (P < 0.05) in the samples collected behind a moving sand dollar than in samples collected in front of the sand dollar. Possible reasons for the enhanced abundances are: (1) increased food availability in the form of mucus and/or excreted cells that line the sand-dollar gut; and (2) increased pore space within the sediment.  相似文献   

4.
The genus Noculacia Mayer, 1903 is reviewed. Two new species, N. africana n. sp. and N. australiensis n. sp., are described based on material collected from southeast Africa and western-southern Australia, respectively. Noculacia bullata Mayer, 1903, the type species of the genus, is redescribed. Noculacia bogisa Mayer, 1903 is transferred to the genus Pseudoprotella Mayer, 1890 mainly on the basis of the presence of a well developed molar, the structure of pereopods 3 and 4, and the setal formula of the mandibular palp being 2-x-1. The genus Noculacia is presently composed of three species: N. africana n. sp., N. australiensis n. sp, and N. bullata Mayer, 1903. The genus Pseudoprotella is composed of P. bogisa (Mayer, 1903), P. inermis Chevreux, 1927, and P. phasma (Montagu, 1804).  相似文献   

5.
The helminth fauna of Litoria genimaculata, a rainforest frog from northern Queensland, was quantified from 53 adult male frogs collected at monthly intervals between April 1990 and March 1991. The helminth fauna of this species was depauperate (6 species: Mesocoelium sp., Parapolystoma bulliense, Austraplectana sp., Onchocercidae gen. sp., Cosmocerca sp. and an unidentified nematode larva). The most commonly encountered species was P. bulliense, but the intestinal infracommanity was dominated by the digenean Mesocoelium sp. Fifty-five per cent of frogs were infected with only 1 helminth species and only 1 frog had more than 2 species, resulting in low diversity values. These results support previous studies which indicate that amphibians have depauperate helminth communities.  相似文献   

6.
本文报道了休氏壮鼠一新亚种--休氏壮鼠云南亚种Hadromys humei yun nanensis subsp.nov.。特征:体型较大,尾长短于体长;耳前有一棕色斑;齿隙较长;腭较短。模式标本采自云南瑞丽县,保存在云南省流行病防治研究所标本室。  相似文献   

7.
Four species of Mesopolobus Westwood were reared as parasitoids of Ceutorhynchinae hosts in Europe during surveys in 2000-2004. An illustrated key is given to differentiate the four species, M. gemellus Baur & Muller sp. n., M. incultus (Walker), M. morys (Walker) and M. trasullus (Walker), plus M. moryoides Gibson, a parasitoid of the cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham), in North America. Pteromalus clavicornis Walker is recognized as a junior synonym of M. incultus syn. n., and Pteromalus berecynthos Walker (also a junior synonym of M. incultus) is considered a correct original spelling. For Disema pallipes F?rster (a junior synonym of Mesopolobus morys), a lectotype is designated. Mesopolobus morys is for the first time accurately associated with the seed weevil Ceutorhynchus turbatus (Schultze), a potential agent for classical biological control, of hoary cress, Lepidium draba L. (Brassicaceae), in North America. Mesopolobus gemellus is associated with another seed weevil, Ceutorhynchus typhae (=C. floralis) (Herbst), in pods of shepherd's purse, Capsella bursa-pastoris (L.) Medik. (Brassicaceae). Implications of the host-parasitoid associations are discussed relative to the introduction of species to North America for classical biological control of the cabbage seedpod weevil.  相似文献   

8.
The green peach aphid, Myzus persicae, is a major pest of tobacco, Nicotiana tabacum, in Yunnan province, China, where its control still depends on the use of insecticides. In recent years, the local government and farmers have sought to improve the biological control of this tobacco pest. In this paper, we present methods for mass rearing Aphidius gifuensis, a dominant endoparasitoid of M. persicae on tobacco plants in this region. The tobacco cultivar K326 (N. tabacum) was used as the host plant and M. persicae as the host insect. In the greenhouse, we collected tobacco seedlings for about 35 days (i.e., until the six-true-leaf stage), transferred them to 7.5-cm diameter pots, and kept these plants in the greenhouse for another 18 days. These pots were then transferred to an insectary-greenhouse, where the tobacco seedlings were inoculated with five to seven wingless adult M. persicae per pot. After 3 days, the infested seedlings were moved to a second greenhouse to allow the aphid population to increase, and after an additional 4±1 days when 182±4.25 aphid adults and nymphs were produced per pot, they were inoculated with A. gifuensis. With this rearing system, we were able to produce 256±8.8 aphid mummies per pot, with an emergence rate of 95.6±2.45%; 69% were females. The daily cost of parasite production (recurring costs only) was US$ 0.06 per 1000 aphid mummies. With this technique, we released 109 800 parasitoids in 1998, 196 000 in 1999, 780 000 in 2000, and 5 600 000 in 2001 during a 2-month period each year. This production method is discussed with respect to countrywide usage in biological control and integrated control of M. persicae.  相似文献   

9.
本文描述了云南省突颚反颚茧蜂属HeratemisWalker1新种─—缺刺反颚茧蜂H.enndisWuetChen,并建立了该属中国已知3种的分种检索表。新种模式标本保存于福建农业大学益虫室。  相似文献   

10.
The biologist's ruler for biodiversity is the species; accurate species identification is fundamental to the conservation of endangered species and in-depth biological scientific exploration. However, the delimitation and affinities of Horsfieldia in China has been controversial, owing in part to very low levels of molecular divergence within the family Myristicaceae. Because species boundaries and phylogenetic relationships within Horsfieldia are also unclear, 13 samples were collected across its distribution in China and their genomes were subjected to shotgun sequencing using Illumina platforms. A total of 40 487 994–84 801 416 pair-end clean reads were obtained and, after assembly, the complete chloroplast genome was recovered for all samples. Annotation analysis revealed a total of 112 genes, including 78 protein-coding genes, 30 transfer RNA, and 4 ribosomal RNA genes. Six variable loci (petN-psbM, trnH-psbA, ndhC-trnV, psbJ-psbL, ndhF, and rrn5-rrn23) were identified. Phylogenetic analyses strongly support the presence of four distinct species of Horsfieldia in China. In addition, samples that had been identified previously as Horsfieldia kingii (Hook. f.) Warb. were indistinguishable from those of H. prainii (King) Warb., suggesting that if H. kingii does occur in China, it was not collected in this study. Similarly, the chloroplast genome of one H. hainanensis Merr. sample from Guangxi province was identical to H. tetratepala C. Y. Wu, suggesting that the distribution range of H. hainanensis might be narrower than assumed previously. The phylogenetic relationships between the Chinese Horsfieldia species based on the whole chloroplast genomes was supported strongly, indicating the potential for using entire chloroplast genomes as super-barcodes for further resolution of the phylogeny of the genus Horsfieldia.  相似文献   

11.
12.
The fatty acid composition of fixed oils obtained from the seeds of 10 species of Nigella (Nigella orientalis L., Nigella oxypetala L., Nigella latisecta P.H. Davis, Nigella segetalis Bieb., Nigella arvensis L., Nigella damascena L., Nigella elata Boiss., Nigella nigellastrum (L.) Willk., Nigella unguicularis (Lam.) Spenner, and Nigella lancifolia Hub.-Mor.) from Turkey have been investigated. The seeds contained 17.6–41.3% fixed oils. Linoleic (31.21–69.5%) and oleic acids (15.79–36.03%) were the major fatty acids in the oils. Eicosenoic acid was found in high amounts in the oils of N. nigellastrum and N. unguicularis seeds (23.12 and 17.47%, respectively). N. nigellastrum, N. elata and N. unguicularis seed oils showed the highest concentration of eicosadienoic acid (9.40, 8.39 and 7.17%, respectively). In all fixed oils, the quantities of unsaturated fatty acids were higher than those of the saturated analogues.  相似文献   

13.
Distribution patterns of the cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham) (Coleoptera: Curculionidae), and its larval parasitoids were investigated in commercial fields of spring canola (Brassica rapa L. and Brassica napus L.) in southern Alberta, Canada, from 2002 to 2004 in relation to developmental stages of its host plants. Adult weevils invaded fields along one or more fronts when crops were in bud to early flower. Significant clustering of adults along field edges in early stages of invasion was followed by more homogeneous distributions as canola reached the mid to late flowering and pod enlargement stages. Larval weevil distributions, as indicated by exit holes in siliques at the end of the season, were often aligned spatially with adult distributions, but they did not coincide in all regions of the fields. The primary ectoparasitoid species attacking weevil larvae comprised Necremnus tidius (Walker) (Hymenoptera: Eulophidae), and Trichomalus lucidus (Walker), Chlorocytus sp., and Pteromalus sp. (Hymenoptera: Pteromalidae). Parasitism rates increased from 0.1 to 5.0% over the three years of study. Parasitoid distributions were often, but not consistently, spatially associated with high densities of C. obstrictus larvae. Lack of close spatial alignment of parasitoids and their hosts probably reflects low parasitoid numbers in comparison with an abundant resource of weevil larvae, and a lack of co-evolutionary history between host and parasitoids. Some parasitoids invaded fields early in host plant development, at the same time that weevils invaded. Unfortunately the synchronous invasions of host and parasitoids indicate that insecticidal applications to reduce adult weevil infestations may be detrimental to these beneficial species.  相似文献   

14.
Laboratory trials were conducted to determine the efficacy of four Bacillus thuringiensis (Bt) Cry toxins at five different concentrations (0.016, 0.08, 0.4, 2, 10 μg/mL) for controlling three lepidopteran stem-borer species (i.e., the pyralid Eldana saccharina and the noctuids Busseola fusca and Sesamia calamistis) as well as to evaluate their indirect effect on the braconid larval parasitoid Cotesia sesamiae. In addition, larvae from the treatments above, after having been parasitized, were either fed a contaminated (group 1) or a toxin-free (group 2) diet and compared with a control (i.e., parasitized larvae which have never fed on Bt-toxin). All Bt Cry toxins induced larval feeding inhibition. Compared with the control, significant mortality resulted at all concentrations and for all species of Lepidoptera. Cry1Ab was the most toxic with 10 days post treatment mortalities ranging from 81% in B. fusca and S. calamistis to 100% in E. saccharina. In contrast, Cry1Ac had comparatively low toxicity particularly for B. fusca and S. calamistis (e.g., respectively, 54 and 74% mortality at 10 days at the highest concentration). In the toxin-treated group 1, percentages of C. sesamiae cocoon-producing moth larvae were higher compared to group 2 and the control, whereas clutch size was higher than in group 2 but similar to the control. In both groups, 0.016, 0.08 μg/mL CrylAc yielded lower female-biased sex ratios than the control. It was suggested that paralyses of the moth larvae caused by the toxin may have facilitated parasitization leading to higher parasitism and clutch size.  相似文献   

15.
16.
Three agricultural regions in southern Ontario (London, Niagara and Guelph) were sampled weekly from May to September for Lygus spp. and their parasitoids in 1998, 1999 and only one region in 2000. Alfalfa was the primary crop sampled, including both “clean” and weedy alfalfa fields. Lygus lineolaris (Palisot de Beauvois) accounted for 99% of all Lygus spp. collected by sweepnet. Lygus lineolaris had two generations (mid-June and late July) on alfalfa with a partial third generation in early September which contributes to the over-wintering adults. In 1998 and 2000, an early first generation peak of Lygus nymphs was observed in mid-May on the weeds, chickweed and shepherd's purse. Overall rates of parasitism (from dissections) for native parasitoids were consistent from year to year and the means of the three regions in each growing season were below 11%. Both nymphs and adult Lygus were parasitized, with the highly mobile adults being a potential means of dispersing the parasitoids. In general weedy fields were more highly parasitized than fields of weed-free alfalfa. Six species of native braconid parasitoids were collected from L. lineolaris in southern Ontario (in decreasing order of occurrence): Peristenus pallipes (Curtis), Peristenus pseudopallipes (Loan), Leiophron lygivorus (Loan), L. solidaginis Loan, L. uniformis (Gahan), and Leiophron sp. near brevipetiolatus Loan. The large populations of Lygus and the low percent baseline parasitism in southern Ontario, particularly of second generation Lygus, support the need for introduction of a multivoltine parasitoid species in this region.  相似文献   

17.
Applied Entomology and Zoology - Four species of Spalangia Latreille (Hymenoptera: Pteromalidae), S. cameroni Perkins, S. endius Walker, S. nigroaenea Curtis, and S. nigra Latreille, were collected...  相似文献   

18.
Thrips palmi is a major pest of many crops in the tropics and sub-tropics, and is a serious threat within the protected horticulture industry in other parts of the world including the UK. Widespread use of insecticides against T. palmi throughout the world coupled with the restricted range of products available makes it essential to find alternative systems for control. The scattered information on its natural enemies, particularly predators and parasitoids, is reviewed and their potential for use in the control of T. palmi as part of IPM strategies in the UK is considered. Natural enemies selected for detailed examination include: Amblyseius spp., Anthocoris nemoralis, Atheta coriaria, Bilia spp., Campylomma spp., Ceranisus spp., Deraeocoris spp., Franklinothrips spp., Hypoaspis spp., Orius spp. and Phytoseius spp. Recommendations for further investigations are made, including screening and efficacy testing of candidate predators and parasitoids, using semiochemicals to enhance their effectiveness, and assessing the compatibility of chosen species with other components of an IPM system.  相似文献   

19.
The grasses are the most important plant family for food production. Despite the domestication of Oryza sativa L. (rice), Triticum aestivum L. (wheat), Zea mays L. (corn), Hordeum vulgare L.(barely), Secale cereale L. (rye), Avena sativa L. (oats), Sorghum bicolor (L.) Moench (sorghum), Saacharum officinarum L. (sugar cane), Pennisetum glaucum (L.) R. Br. (pearl millet), Panicum virgatum L. (switchgrass), Eleusine coracana (L.) Gaertn (finger millet.) and Eragrostis tef (Zucc.) Trotter (tef), the family has not been widely studied biogeographically (Bouchenak-Khelladi et al.,2010). Other notable economic uses of grasses include landscaping, construction (primarily bamboos), and biofuel production (Miscanthus x giganteus J.M. Greef & Deuter ex Hodk. & Renvoize, Panicum L., and Zea L.).  相似文献   

20.
Parasites morphologically consistent with Anisakis simplex sensu lato collected from the coast of Japan and Western North Pacific Ocean were examined by PCR-RFLP of the ITS region (ITS1, 5.8 subunit rRNA gene and ITS2) and mtDNA cox1. The RFLP patterns of rDNA generated by HinfI and HhaI showed that 100% of the larvae collected from Hokkaido and 94% of adults collected from Western North Pacific Ocean were identified as A. simplex sensu stricto. On the other hand, 97% of the larvae collected from Fukuoka prefecture were identified as A. pegreffii. A hybrid genotype was found in adults in Western North Pacific Ocean and larva in Fukuoka prefecture. These findings revealed that A. simplexs. str. is primarily distributed in the North Pacific Ocean and A. pegreffii is primarily distributed in the southern Sea of Japan. RFLP analysis of mtDNA cox1 showed different patterns between A. simplex s. str. and A. pegreffii after digestion with HinfI. This polymorphism obtained by RFLP analysis of mtDNA cox1 proved the usefulness as new genetic markers to distinguish two sibling species.  相似文献   

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