祁连山北麓天然草原主要蝗虫雄性外生殖器形态特征分析

Comparison of male external genitalia of nine grasshoppers in the pasture at the northern foot of the Qilian Mountains

中文关键词:天然草原  肃南县  蝗虫  雄性外生殖器  主成分分析

keywords:pasture  Sunan County  grasshopper  male external genitalia  principal component analysis

中文摘要:为准确识别祁连山北麓天然草原主要蝗虫种类以科学防治蝗虫，采集当地优势种亚洲小车蝗Oedaleus decorus asiaticus、小翅雏蝗Chorthippus fallax，常见种东方雏蝗Chorthippus intermedius、宽须蚁蝗Myrmeleotettix palpalis、宁夏束颈蝗Sphingonotus ningsianus以及稀有种黄胫异痂蝗Bryodemella holdereri、祁连山短鼻蝗Filchnerella qilianshanensis、肃南短鼻蝗Filchnerella sunanensis、北方雏蝗Chorthippus hammarstroemi共9种蝗虫，于室内进行雄性外生殖器解剖及其结构特征描述，并选取7项指标进行主成分分析，以对基于其他外部形态特征不易区分的种类进行种间分类。结果显示：供试9种蝗虫雄性外生殖器差异在于阳具基背片形状、侧板边缘凹凸程度、后突形状等，可用于以上种类鉴定。雄性外生殖器指标主成分分析结果显示，特征值大于1.00的成分因子有2个，第1主成分主要包括锚状突外侧间距、两锚状突间距、锚状突内侧间距和后突外侧间距，第2主成分主要为阳具基背片桥宽，二者总贡献率为88.14%。表明利用雄性外生殖器的主要特征锚状突、后突、冠突、桥宽的相对位置，可以准确区分祁连山北麓天然草地供试的9种蝗虫。

Abstract:To identify common grasshopper species in the pasture of the northern foot of the Qilian Mountains, this study used traditional anatomical methods to obtain the male external genitalia of nine species: Oedaleus decorus asiaticus, Myrmeleotettix palpalis, Sphingonotus ningsianus, Bryodemella holdereri, Filchnerella qilianshanensis, Filchnerella sunanensis, Chorthippus intermedius, Chorthippus hammarstroemi and Chorthippus fallax. The morphological characteristics of their male external genitalia were described, and seven indicators were selected for principal component analysis. The results showed that the differences in the male external genitalia were the overall shape of the basal dorsal part of the penis, the convexity of the lateral plate edge, and the shape of the posterior process. The results of principal component analysis revealed two component factors with eigenvalues greater than 1.00. The first principal component included the lateral distance of the ancorae, the distance between two ancorae,the measured distance within the ancorae, and the lateral distance of posterior process. The second principal component was bridge width. The total contribution rate of these two components was 88.14%. In conclusion, the main characteristics of male external genitalia in grasshoppers are the relative positions of anchor-shaped process, posterior process, coronoid process, and bridge width, in that order. Therefore, these characteristics can be used as the basis for studying the relationship and classification of the nine locust species in the pasture of the northern foot of the Qilian Mountains.