Aeschnidiid nymphs are here first identified and described, and its phylogenetic relationship and bioecological characteristics are deduced. The nymphs known from China, Mongolia, Russia and Brazil and arranged in the...Aeschnidiid nymphs are here first identified and described, and its phylogenetic relationship and bioecological characteristics are deduced. The nymphs known from China, Mongolia, Russia and Brazil and arranged in the family Aeschnidiidae are, in fact, unrelated to this group. All the known five Chinese species in four genera which were erected based on fossil nymphs and placed in the family Gomphidae may be transferred in Aeschnidiidae and merged into one alone, the Sinaeschnidia cancellosa. It is a geographically widespread species from the 'Jehol biota' of East Asia and appeared in the latest Late Jurassic age.展开更多
We used brightfield electron microscopy (BEM), differential interference contrast microscopy (DICM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and confocal laser scanning micr...We used brightfield electron microscopy (BEM), differential interference contrast microscopy (DICM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and confocal laser scanning microscopy (CLSM) to investigate the stylet pathways of Bemisia tabaci during nymphal feeding behavior in cotton leaves beginning with penetration of the abaxial leaf surface and ending with stylets in sieve tubes in phloem tissues. Most nymphal stylets within salivary sheaths penetrating leaf tissues made complex turns and developed more than one salivary sheath branch before ending in sieve tubes. The external morphology of the salivary sheaths and their routes between and through leaf cells are described during the present study. Results showed the presence of the stylet within the sieve tubes. B. tabaci nymphs may remove stylets and feed in different sieve tubes. Ten short movies showing the progression of the stylet penetrations from adaxial surface to the sieve tubes are attached to Figures 8-15. The report and movies can be viewed from the internet. Download the movies to a local drive in your computer first for fast upload. The movies are posted on the website http://www.ars.usda.gov/Services/docs.htm?docid=14629. The movies can be used as a teaching aid in biology classes.展开更多
This research presents new information on the biology ofKermes quercus (L.). Observations were carried out in 2009 in the city of Warsaw and surroundings (Poland). Material was collected on Quet;cus robur L. betwe...This research presents new information on the biology ofKermes quercus (L.). Observations were carried out in 2009 in the city of Warsaw and surroundings (Poland). Material was collected on Quet;cus robur L. between the end of January until the beginning of November. The sampling each month was divided into three ten-day periods: I - from the 1st till 10th day of the month, II - from ! lth till 20th day of the month, and Ill - from 21st till 30th day of the month. The material was sampled at least once in each period. All live specimens of K. quercus were picked off and the developmental stages were identified. The observations revealed that, almost exclusively lst-instar nymphs occurred during the winter and they remained in this stage throughout the spring and summer until the last third of August. The process of moulting from 1st instar to 2nd instars started in the last third of August and lasted about 2 weeks. In autumn the 2nd-instars nymphs entered the winter diapause. The results suggest that, under the climatic conditions of Poland, Kermes quercus L. is not a univoltine species. Each generation probably develops through two years - in the first year overwintering as the lst-instar nymphs and in the second year as the 2nd-instar nymphs.展开更多
研究了上海市水源涵养林内樟颈曼盲蝽(Mansoniella cinnamomi(Zheng et Liu,1992))的生活史和生物学习性,以及若虫的龄期划分和各龄若虫的形态特征。依据樟颈曼盲蝽若虫头宽值频次和形态特征,其若虫共分5龄,1~5龄若虫的头宽值分别为(0....研究了上海市水源涵养林内樟颈曼盲蝽(Mansoniella cinnamomi(Zheng et Liu,1992))的生活史和生物学习性,以及若虫的龄期划分和各龄若虫的形态特征。依据樟颈曼盲蝽若虫头宽值频次和形态特征,其若虫共分5龄,1~5龄若虫的头宽值分别为(0.23±0.03)、(0.34±0.02)、(0.47±0.03)、(0.57±0.02)、(0.68±0.03)mm,并详细描述了各龄若虫的形态特征。该虫在上海地区一年发生4代,以卵在叶柄、叶主脉及嫩梢皮层内越冬,具有明显的世代重叠现象。确定了樟颈曼盲蝽各世代的发生历期,编制了其在上海地区的生活史表,详细观察记录了成虫的羽化、交尾、产卵等习性和若虫的活动、取食及脱皮等习性。展开更多
文摘Aeschnidiid nymphs are here first identified and described, and its phylogenetic relationship and bioecological characteristics are deduced. The nymphs known from China, Mongolia, Russia and Brazil and arranged in the family Aeschnidiidae are, in fact, unrelated to this group. All the known five Chinese species in four genera which were erected based on fossil nymphs and placed in the family Gomphidae may be transferred in Aeschnidiidae and merged into one alone, the Sinaeschnidia cancellosa. It is a geographically widespread species from the 'Jehol biota' of East Asia and appeared in the latest Late Jurassic age.
文摘We used brightfield electron microscopy (BEM), differential interference contrast microscopy (DICM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and confocal laser scanning microscopy (CLSM) to investigate the stylet pathways of Bemisia tabaci during nymphal feeding behavior in cotton leaves beginning with penetration of the abaxial leaf surface and ending with stylets in sieve tubes in phloem tissues. Most nymphal stylets within salivary sheaths penetrating leaf tissues made complex turns and developed more than one salivary sheath branch before ending in sieve tubes. The external morphology of the salivary sheaths and their routes between and through leaf cells are described during the present study. Results showed the presence of the stylet within the sieve tubes. B. tabaci nymphs may remove stylets and feed in different sieve tubes. Ten short movies showing the progression of the stylet penetrations from adaxial surface to the sieve tubes are attached to Figures 8-15. The report and movies can be viewed from the internet. Download the movies to a local drive in your computer first for fast upload. The movies are posted on the website http://www.ars.usda.gov/Services/docs.htm?docid=14629. The movies can be used as a teaching aid in biology classes.
文摘This research presents new information on the biology ofKermes quercus (L.). Observations were carried out in 2009 in the city of Warsaw and surroundings (Poland). Material was collected on Quet;cus robur L. between the end of January until the beginning of November. The sampling each month was divided into three ten-day periods: I - from the 1st till 10th day of the month, II - from ! lth till 20th day of the month, and Ill - from 21st till 30th day of the month. The material was sampled at least once in each period. All live specimens of K. quercus were picked off and the developmental stages were identified. The observations revealed that, almost exclusively lst-instar nymphs occurred during the winter and they remained in this stage throughout the spring and summer until the last third of August. The process of moulting from 1st instar to 2nd instars started in the last third of August and lasted about 2 weeks. In autumn the 2nd-instars nymphs entered the winter diapause. The results suggest that, under the climatic conditions of Poland, Kermes quercus L. is not a univoltine species. Each generation probably develops through two years - in the first year overwintering as the lst-instar nymphs and in the second year as the 2nd-instar nymphs.
文摘研究了上海市水源涵养林内樟颈曼盲蝽(Mansoniella cinnamomi(Zheng et Liu,1992))的生活史和生物学习性,以及若虫的龄期划分和各龄若虫的形态特征。依据樟颈曼盲蝽若虫头宽值频次和形态特征,其若虫共分5龄,1~5龄若虫的头宽值分别为(0.23±0.03)、(0.34±0.02)、(0.47±0.03)、(0.57±0.02)、(0.68±0.03)mm,并详细描述了各龄若虫的形态特征。该虫在上海地区一年发生4代,以卵在叶柄、叶主脉及嫩梢皮层内越冬,具有明显的世代重叠现象。确定了樟颈曼盲蝽各世代的发生历期,编制了其在上海地区的生活史表,详细观察记录了成虫的羽化、交尾、产卵等习性和若虫的活动、取食及脱皮等习性。