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1.
记述采自内蒙古贺兰山的膜翅目Hymenoptera、叶蜂科Tenthredinidae、平背叶蜂亚科Allantinae 1新种:贺兰山曲叶蜂Emphytus helanshanicus Wei,Li & Xiao,sp.nov.,该种与亚美曲叶蜂E.nigrotibialis Rohwer,191 1最近似,但前者后...  相似文献   
2.
记述中国叶蜂科盔叶蜂属1新种:光额盔叶蜂Corymbas glabrifrons sp.nov..该种与日本分布的C.aperta Takeuchi,1919相似,但上唇和后足转节白色,单眼后区宽长比为3:2,雌虫腹部第3、4节黑色,两侧具白斑,触角第3节短于第4节2倍长(40:27),腹部第1节背板大部光滑,其余各节背板均具显著细横刻纹,雄虫各足股节浅褐色,雌虫锯腹片具29个锯刃,锯刃稍倾斜.  相似文献   
3.
Heterogeneity in the quality of oviposition and feeding sites within plants can significantly influence the distribution and abundance of herbivorous insects, but remains poorly understood. Field surveys and a manipulative study were conducted to evaluate the influence of variation within the crown of black spruce, Picea mariana (Mill.) B.S.P. (Pinaceae), on adult oviposition and larval feeding behavior of yellowheaded spruce sawfly, Pikonema alaskensis Rohwer (Hymenoptera: Tenthredinidae). Most eggs were laid in the mid to lower crown of 1.5–2 m tall trees. However, most of the few eggs that were laid in the upper crown (i.e., whorl 2) were female. Fourth and fifth instars dispersed acropetally, from the mid and lower to the upper crown, causing high defoliation in the upper crown. Late-instar females were generally more abundant than males on the leader, the most apical shoot on a tree where eggs and early instars rarely occurred, strongly suggesting that more females than males disperse acropetally. This hypothesis was supported in a manipulative experiment, where only 15–20% of larvae in all-male broods, but almost three-quarters of larvae in mixed broods, dispersed to the upper crown. To our knowledge, this is only the second study to explicitly demonstrate preferential allocation of progeny sex through oviposition site selection by a herbivorous insect, and the first study to unambiguously demonstrate sex-biased dispersal by the juveniles of an insect whose adult females can fly. This study emphasizes the important role of intra-plant variation in shaping both oviposition site selection and the dispersal behavior of juvenile phytophagous insects within their hosts, and suggests that sex-biased foraging behaviors may be necessary for some insects to accommodate the respective needs of immature females and males within heterogeneous host plants.  相似文献   
4.
记述采自云南及四川省的方颜叶蜂属Pachyprotasis两新种:郑氏方颜叶蜂Pachyprotasis zhengi Wei et Zhong,sp.nov.和程氏方颜叶蜂Pachyprotasis chenghanhuai Wei et Zhong,sp.nov..新种模式标本保存在中南林业科技大学昆虫模式标本室.  相似文献   
5.
记述中国叶蜂亚科2新种:孙氏金蓝叶蜂Metallopeus sunae Wei et Zhang,sp.nov.和光额横带叶蜂 Tenthredo nitidifrontalia Wei et Zhang,sp.nov.前者隶属于金蓝叶蜂属Metallopeus Malaise,1934,后者隶属于叶蜂属Tenthredo Linnaeus,1758的横带叶蜂种团T.pompilina group.金蓝叶蜂属的分布纪录向北延伸约10个纬度.  相似文献   
6.
记述了采自中国河南省太行山区和福建光泽的叶蜂科粘叶蜂属1新种:半环粘叶蜂Caliroa semicincta Wei,sp.nov.。该新种与欧洲种C.annulipes(Klug,1814)比较近似,但后足胫节基部3/5和基跗节基部4/7白色,触角第3节等长于端部4节之和,前翅2r脉等长于Rs脉第4段,锯腹片锯刃内外侧均具2枚明显的亚基齿,刃间膜等宽于锯刃,并明显鼓起,节缝刺毛带很宽,最宽处等宽于带间距等,与后者不同。新种模式标本保存于中南林业科技大学模式昆虫标本室。  相似文献   
7.
Abstract. 1. A group of six unusual sawfly species, which do not conform to the phylogenetic constraints hypothesis as it has been applied to sawflies, was examined in natural populations. All species were in the genus Pontania (Hymenoptera: Tenthredinidae), which induce galls on leaves of willow species (Salicaceae). An understanding of these non‐conformist species was important as a test of the validity of the general hypothesis. 2. The six species of sawfly, Pontania mandshurica, P. cf. arcticornis, P. aestiva, P. arcticornis, P. pacifica, and P. nr. pacifica, showed no oviposition preference for long, vigorous shoots, in contrast to 37 documented tenthredinid species that have demonstrated such a preference. Rather, the non‐conformist species attacked the shortest shoot length classes more frequently and larval establishment in galls was successful. 3. The evident escape from the phylogenetic constraint, which commonly limits sawfly attack to the most vigorous shoots in a willow population, resulted from low apparent heterogeneity of the resources exploited by these Pontania species. At the time of female oviposition, shoots and leaves were too uniform to allow discrimination by females among shoot length classes, resulting in random, or near random attack of shoots. 4. The unusual relative uniformity of resources to which sawflies were exposed resulted from several characteristics. (1) Females emerged early relative to shoot growth phenology, making discrimination among shoot length and vigour difficult or impossible. (2) Low heterogeneity in leaf length resulted in resource similarity independent of shoot length. (3) Abscission of leaves occurred after emergence of larvae from leaf galls so that differential abscission of leaves in relation to shoot length became irrelevant. (4) In some cases, low variance in shoot lengths was evident in old ramets lacking long, vigorous shoots. Probably as a result of low resource heterogeneity, larvae survived well across all shoot length classes, revealing no ovipositional preference and larval performance linkage related to the exploitation of the longest shoot length classes in a population of willows, as in the conformist species. Therefore, larval survival did not provide positive feedback on female preferential behaviour for long shoots, as in the conformist species studied.  相似文献   
8.
The effect of temperature on egg development of the apple sawfly Hoplocampa testudinea Klug was studied under controlled conditions. Based on a linear model describing the relationship between temperature and developmental rates a thermal threshold of 6.9 °C and a thermal constant of 85 day-degrees were established. The experimental results were used to expand and parameterise an existing phenology model to include egg development and hatching of first instar larvae. The model thus became a valuable forecasting tool not only for adult emergence and the optimal monitoring period but also for egg hatch and the best timing of control measures against first instar larvae. The model was validated by comparing predictions with independent observations on egg-laying and subsequent hatching of first instar larvae under semi-field conditions.  相似文献   
9.
Type specimens of seven nominal species of sawfly described by Edward Newman and one by Charles Healy were studied. This material is housed in the Oxford University Museum of Natural History, United Kingdom. The following new synonymies are proposed (valid names in parentheses): Hartigia Schiødte, 1839 (Phylloecus Newman, 1838), Cephus helleri Taschenberg, 1871 (Phylloecus faunus Newman, 1838) and Euura gallae Newman, 1837 (Euura mucronata (Hartig, 1837)). The type species of Euura Newman, 1837 and Euura subgenus Gemmura E. L. Smith, 1968 belong to the same taxonomic species, Euura mucronata (Hartig, 1837), so that these genus group names become new synonyms. Lectotypes are designated for Phyllotoma tormentillae Healy, 1868, Fenusa ianthe Newman, 1837, Fenusa parviceps Newman, 1837, Selandria pallida Newman, 1837 and Phylloecus faunus Newman, 1838. 26 new combinations are proposed for species formerly placed in Hartigia and here transferred to Phylloecus, and 4 original combinations are re-instated as valid.  相似文献   
10.
Laboratory feeding experiments using two transgenic Bacillus thuringiensis (Bt) rape cultivars (Bt‐Westar and Bt‐Oscar) both expressing the Cry1Ac protein, and the corresponding untransformed lines, were carried out to study the effects of transgenic Bt rape on the non‐target herbivore Athalia rosae (L.) (Hymenoptera: Tenthredinidae). Furthermore, Cry1Ac protein concentration in Bt rape leaves, A. rosae larvae fed Bt rape, their faeces, eonymph instars, pupae, and adults were quantified using an enzyme‐linked immunosorbent assay (ELISA). There were no significant differences in mortality, larval development, and weight between transgenic Bt rape and non‐transgenic rape fed A. rosae. Additionally, we did not detect any significant differences in the fecundity and fertility of adult females either fed as larvae with transgenic Bt or with non‐transgenic rape. However, results of the ELISA indicated that Cry1Ac protein was detectable in larvae and faeces (Bt‐Westar 1.1 ± 0.2 and Bt‐Oscar 0.3 ± 0.2 µg Cry1Ac protein/g fresh weight) although this was less than in the leaf material, where concentrations were 2.2 ± 0.8 µg Cry1Ac protein/g fresh weight for Bt‐Westar and 7.5 ± 2.9 µg Cry1Ac protein/g fresh weight in Bt‐Oscar. In contrast, Cry1Ac protein could not be detected in eonymphs, pupae, or adults of A. rosae. Our results suggest that Cry1Ac protein in Bt rape does not have a significant effect on the herbivore A. rosae but the protein is still detectable after ingestion and excretion by these herbivores, thus providing the possibility of exposure to organisms other than herbivores.  相似文献   
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