普通齿蛉和单斑巨齿蛉(广翅目:齿蛉科)卵块及1龄幼虫形态学研究

Morphological study of egg mass and first-instar larvae of Neoneuromus ignobilis and Acanthacorydalis unimaculata(Megaloptera:Corydalidae)

本文以普通齿蛉Neoneuromus ignobilis Navás,1932和单斑巨齿蛉Acanthacorydalis unimaculata Yang et Yang,1986为例,描述和比较了广翅目齿蛉科齿蛉属和巨齿蛉属的卵块及1龄幼虫形态特征。结果显示普通齿蛉与单斑巨齿蛉的卵块和1龄幼虫在形态上有着较大差异:普通齿蛉卵块约为单斑巨齿蛉卵块的3/4;普通齿蛉卵粒约为单斑巨齿蛉卵粒的2/3,卵粒都呈圆柱形,差异不大;普通齿蛉外层白色覆盖物厚度是单斑巨齿蛉的2-3倍。普通齿蛉卵块为单个附着在芦苇叶上,形状有4种类型,分别为椭圆形、螺形、卵圆形、圆形,在所有样本中其占比分别依次为47.1%、9.8%、17.6%和25.5%;单斑巨齿蛉卵块多为数个相连附着在桥底,卵壳薄且最外层卵粒向外翘起,使其表面如突起均匀地分布在卵壳表面。普通齿蛉1龄幼虫腹部背面白色的线状裸露区较稳定,且8对气管鳃靠近末端都有褐色和黄色的斑纹,而单斑巨齿蛉1龄幼虫腹部背面呈深褐色,腹部背面裸露区和颜色分布不稳定,气管鳃无花斑;两种1龄幼虫腹部两侧均都无毛簇。这些数据资料不仅丰富了广翅目昆虫的相关知识,而且为其产业化应用提供了参考。

This paper described and compared the morphological characteristics of egg masses and first-instar larvae of the genus Neoneuromus and Acanthacorydalis from the family Megaloptera,taking Neoneuromus ignobilis Navás,1932 and Acanthacorydalis unimaculata Yang et Yang,1986 as examples.The results showed that the morphology of egg masses and first-instar larvae of N.ignobilis and A.unimaculata were quite different:The egg mass of N.ignobilis was about three-fourths of that of the egg mass of A.unimaculata,and the egg of N.ignobilis was about two-thirds of the egg of A.unimaculata.Their eggs were cylindrical with almost no difference.The thickness of the outer white covering of N.ignobilis was 2-3 times that of A.unimaculata.Egg masses were attached to reed leaves individually,and there were 4 types of shapes,namely oval,spiral,egg-shape,and round,and their types in all samples accounted for 47.1%,9.8%,17.6%and 25.5%respectively.The egg masses of A.unimaculata were mostly attached to the bottom of the bridge,the egg shells were thin and the outermost eggs were lifted outwards,so that their surfaces such as protrusions were evenly distributed on the eggshell surface.The first-instar larvae of N.ignobilis had white linear bare area on the abdomen,and there were brown and yellow markings near the ends of the 8 pairs of tracheal gills.However,the back of the first-instar larva of A.unimaculata was dark brown,the linear bare area and color distribution were unstable,and their tracheal gills had no marking as N.ignobilis.Two types of first-instar larvae had no bristles on both sides of the abdomen.These data would not only enrich the related information of Megaloptera,but also provided references for their industrialization.