草地贪夜蛾成虫与灯下4种相似种的形态特征比较

Morphological differences among Spodoptera frugiperda and other four similar noctuid species in light trap

草地贪夜蛾Spodoptera frugiperda(J.E.Smith)是2019年新入侵我国的一种重大迁飞性害虫,在灯诱监测过程中,草地贪夜蛾成虫易与旋歧夜蛾Anarta trifolii(Hufnagel)、陌夜蛾Trachea atriplicis(Linnaeus)、甘蓝夜蛾Mamestra brassicae(Linnaeus)、斜纹夜蛾Spodoptera litura(Fabricius)4种夜蛾的成虫混淆。本文通过制作标本进行形态鉴定,并结合相关资料进行对比分析,发现翅面颜色、斜纹位置和长度、顶角特征等有助于几种夜蛾的区分,此外,前足基部明显膨大也是识别草地贪夜蛾的关键特征。草地贪夜蛾的雄性外生殖器容易与斜纹夜蛾的混淆,与其他两种有明显区别。掌握关键分类特征,可以准确识别上述5种夜蛾,为草地贪夜蛾的预测预报奠定基础。

The fall armyworm,Spodoptera frugiperda(J.E.Smith),as a vital migratory insect pest to corn,was found invaded to China in 2019.Morphologically,the adult of fall armyworm was not easy to be differentiated with adults of Anarta trifolii(Hufnagel),Trachea atriplicis(Linnaeus),Mamestra brassicae(Linnaeus)and Spodoptera litura(Fabricius).In this paper,the morphological characteristics of these five noctuid species were described and compared.The results showed that for the intact forewings,features such as the forewings color,the position and length of slant strip,characteristics at or near the tip were useful for the identification of these noctuid species.The morphological characteristics of male genitalia can also be used for the identification of these species except for the fall armyworm and Spodoptera litura.In addition,the evident enlargement at the base of the forefoot is also a key feature of fall armyworm moths.With those key features,these five noctuid species can be accurately identified,which lays an important foundation for monitoring of noctuids.