光肩星天牛和黄斑星天牛混合种群的显微特征比较

鞘翅上斑纹的颜色是传统形态分类区分光肩星天牛和黄斑星天牛的重要外部形态特征 ,光肩星天牛的鞘翅斑纹颜色多为乳白色 ,而黄斑星天牛则为黄色 .在许多地区 ,如宁夏青铜峡市 ,光肩星天牛和黄斑星天牛以混合种群的方式存在和共同危害 .这种混合种群中出现了许多鞘翅斑纹颜色介于乳白色和黄色之间的“过渡类型”个体 .作者从同一寄主合作杨上的该混合种群中采集了近千只成虫标本 ,按鞘翅斑纹从乳白色自然、连续地过渡到黄色的颜色序列 ,从标本中选取 12只成虫 ,分别代表序列上鞘翅斑纹颜色深浅不同的个体 ,并从左到右依次编为 1～ 12号 .利用扫描电镜对这 12个体的斑纹、触角、下唇须、下颚须、前胸音锉及跗垫进行了超微结构的观察和比较 ,以探讨光肩星天牛、黄斑星天牛和“过渡类型”三者间超微形态特征的关系 .结果表明 ,从乳白色到黄色 ,斑纹上的分泌物表现出了从少到多的连续变化趋势 ,而在触角、下唇须、下颚须、前胸音锉及跗垫部位上则无显著的差异 .

Comparison of microscopic characters of mixed population of Anoplophora glabripeonis (Motschulsky) and A. Nobilis (Ganglbauer)

The color of elytral stain is an important morphological character traditionally distinguishing Anoplophora glabripennis (Motschulsky) from A. nobilis (Ganglbauer). The typical stain color of A. glabripennis is white, but that of A. nobilis is yellow. In some areas in China, such as Qintongxia City of Ningxia Hui Autonomous Region, these two Anoplophora species exist and attack trees as mixed population. In such population, there are many "median type" whose stain color is between white and yellow. In this study, the authors collected about one thousand specimens from such mixed population from the host Populus 'Opera' (Hsu) in Qintongxia City. According to the sequence on which the stain color changes from white to yellow naturally and continuously, the authors selected 12 individuals representing 12 different types of stain color on the sequence. Using scanning electronic microscopy, the microscopic characters, including stain, antenna, labial palp, maxillary palp, lima and tarsal pulvillus, of every individual on the sequence were observed. The relationship of microscopic characters among Anoplophora glabripennis, A. nobilis and the "median type" was discussed. The results demonstrate that, on the sequence, the amount of secretion of the stain has an augmenting trend, but other microscopic characters have no obvious distinction.