Feasibility Of Identification Of 3 Lymantriid Moths Based On Morphological Characteristics Of Wing Veins

The gypsy moth,Lymanria dispar(Linnaeus,1758)(Insecta:Lepidoptera:Erebidae:Lymantriinae),is an important quarantine pest.There are two important relative species of gypsy moth in China,which are L.monacha(L.)and L.xylina Swinhoe.The morphological and behavioral characteristics between them are very similar and it is easy to confuse them.The identification of gypsy moth and its relative species requires the staff to have certain professional knowledge and long-term experience accumulation.The identification is time-consuming and subjective.The existing form description can not meet the high requirements of port quarantine for fast customs clearance.In view of this,there is an urgent need for a convenient,fast,accurate and practical,comprehensive and systematic method for the classification and identification of Chinese Lymantriid moths,to improve the efficiency of grass-roots workers.We collected 15 gypsy moths from 9 different geographical populations and their relative species,L.monacha(L.)and L.xylina Swinhoe,respectively.The scales of the right forewing of Lymantriid moths were removed with chemical methods and images were collected.The images of the right forewings of the Lymantriid moths were grayed and sharpened by photoshop software.Based on the geometrical morphometry method,7 and 15 landmarks were selected from the right forewing of the Lymantriid moths by tpsDig2 software.The influence of non-shape factors was eliminated by PAST software after Platts overlaying.The SPSS software was used to analyze the variance and discriminate the relevant data to explore the feasibility of the characteristics of the wing veins in the differential identification of Lymantriid moths.The main results are as follows:1.After Platts overlaying,the discriminant analysis of 9 different geographical populations of gypsy moths was carried out by using the distance between adjacent landmarks of the right forewing.The original discriminantion accuracy and the cross-validated discrimination accuracy were low.Discriminant analysis of gypsy moth and its relative species was carried out by the same method.The original discriminantion accuracy was 97.8%and the cross-validated discrimination accuracy was 93.3%,which indicates that after Platts overlaying,the method can better classify gypsy moth and its relative species.2.The discriminant analyses of 9 different geographical populations of gypsy moths were carried out by using the original coordinates of 7 and 15 landmarks of the right forewing respectively.The original discriminantion accuracy and the cross-validated discrimination accuracy were all low.After using the Platts overlay to eliminate the influence of non-shape factors,the original discriminantion accuracy and the cross-validated discrimination accuracy were close to 100%,which indicates that results of discriminant analysis were good.Discriminant analysis of gypsy moth and its relative species was carried out by the same method,the accuracy of original discrimination and cross-validated discrimination was 100%.The above studies show that after Platts overlaying,both 7 and 15 landmarks of the right forewing can be used for the classification and identification of different geographical populations of gypsy moth and its relative species.The above two methods can provide grass-roots workers and port quarantine personnel with an auxiliary basis for identifying gypsy moths,and provide technical basis and theoretical support for solving the Sino-US trade dispute caused by gypsy moths.