Morphological variations and discriminanant analysis on Thitarodes pupae in Mt.Segrila
Larvae of the genus Thitarodes,as the host of entomopathogenic fungus Ophiocordyceps sinensis,have great economic importance in the Tibetan Plateau.There are two Thitarodes species reported in Mt.Segrila,T.pui and T.sejilaensis.It is hard to distinguish the two species before eclosion because of the same life history,close distribution,and almost the same morphology.We firstly report here the pupae morphological variations among three geographical populations of two Thitarodes species.Five morphological characters were measured.The data were statistically analyzed by analysis of significance of difference and three muhivariation analysis methods.The results of cluster analysis and principal component analysis showed a high similarity in intraspecific and a significant difference in interspecific.T.pui had significantly larger size of pupa than that of T.sejilaensis.Remarkable sexual size dimorphism was observed in both two species,which male pupae typically smaller than female pupae.The discriminant functions were established for sex & species identification of two species,and the discriminant accuracy was 100％ for any of the four types of Thitarodes pupae (T.sejilaensis ♂;T.sejilaensis ♀;T.pui ♂;T.pui ♀) in Mt.Sejila,and the comprehensive discriminant accuracy rate was 100％ also.It could be concluded that T.pui and T.sejilaensis will be distinguished quicky and accurately based on pupae morphological characters,and the sex of pupa will be determined.In consideration of the characteristic distribution & differentiation pattern of genus Thitarodes,the methods used in this paper should be universality and could be used to identify Thitarodes specimen distributed in other geographical region when they are in the period of pupal stage.
NETL
NSTL
万方数据
维普
