昆虫学报 ›› 2016, Vol. 59 ›› Issue (10): 1133-1142.doi: 10.16380/j.kcxb.2016.10.012

• 研究论文 • 上一篇    下一篇

大双角蝎蛉幼虫复眼超微结构及其在全变态类幼虫侧单眼演化中的意义

陈庆霄1,2, 花保祯1,*   

  1. (1. 西北农林科技大学植物保护学院, 植保资源与病虫害治理教育部重点实验室, 陕西杨凌 712100; 2. 河南科技大学林学院, 河南洛阳 471023)
  • 出版日期:2016-10-20 发布日期:2016-10-20

Ultrastructure of larval compound eyes of Dicerapanorpa magna (Mecoptera: Panorpidae) and its implications for the evolution of stemmata of holometabolous larvae

CHEN Qing-Xiao1,2, HUA Bao-Zhen1,*   

  1. (1. Key Laboratory of Plant Protection Resources and Pest Management of the Education Ministry, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China; 2. Forestry College, Henan University of Science and Technology, Luoyang, Henan 471023, China)
  • Online:2016-10-20 Published:2016-10-20

摘要: 【目的】长翅目(Mecoptera)是全变态类昆虫中唯一在幼虫期具有复眼而无侧单眼的类群,是研究昆虫复眼与侧单眼之间演化关系的理想材料。本研究旨在阐明长翅目幼虫复眼的结构特征,为探讨长翅目幼虫复眼与其他全变态类幼虫侧单眼之间的进化关系提供依据。【方法】本研究运用光学显微镜、扫描和透射电子显微镜技术观察了蝎蛉科(Panorpidae)大双角蝎蛉Dicerapanorpa magna (Chou)幼虫复眼的超微结构,并依据其结构特征对长翅目幼虫复眼在全变态类幼虫侧单眼演化中的意义进行了探讨。【结果】结果表明,大双角蝎蛉幼虫复眼属于并列像眼,由50多个小眼组成。小眼由1个角膜、1个晶体、8个视网膜细胞、2个初级色素细胞和数个次级色素细胞等组成。视网膜细胞分为4个远端细胞和4个近端细胞。远端视网膜细胞的视小杆向上延伸包裹着晶体的基部,使视杆末端呈漏斗状。【结论】分层的视网膜细胞和漏斗状的视杆很可能是长翅目幼虫复眼的共有祖征。这两个特征不存在于长翅目成虫复眼中,但存在于许多渐变态类昆虫中。由此推测,长翅目幼虫复眼可能与渐变态类昆虫的复眼存在同源关系。我们认为,长翅目幼虫独有的复眼很可能是全变态类昆虫的祖征,其他全变态类幼虫的侧单眼可能是由复眼演化来的。

关键词: 大双角蝎蛉, 幼虫, 小眼, 视网膜细胞, 视杆, 超微结构, 进化

Abstract: 【Aim】 Mecoptera are unique in Holometabola in that their larvae possess a pair of compound eyes instead of stemmata, thus becoming ideal materials for uncovering the evolutionary relationship between compound eyes and stemmata in insects. This study aims to elucidate the structural features of the compound eyes of larval Mecoptera and to provide evidence for exploring the evolutionary relationship between the compound eyes of larval Mecoptera and the stemmata of other holometabolous larvae. 【Methods】 In this study, we observed the ultrastructure of the larval compound eyes of the scorpionfly Dicerapanorpa magna (Chou) using light, scanning and transmission electron microscopy and explored implications of the compound eyes of larval Mecoptera in the evolution of the stemmata of holometabolous larvae based on these structural features. 【Results】 The results showed that the compound eyes of larval D. magna are of the apposition type, each eye comprising more than 50 ommatidia. The ommatidium consists of a cornea, a crystalline cone, eight retinula cells, two primary pigment cells, and several secondary pigment cells. In the larval ommatidia, these retinula cells are arranged into four distal and four proximal cells. The rhabdomeres of the distal retinula cells extend up to surround the basal surface of the crystalline cone, so that the rhabdom assumes distally a funnel shape. 【Conclusion】 Layered retinula cells and the funnel-shaped rhabdoms are very likely the ground plan of the compound eyes in larval Mecoptera. These two characters are absent in imaginal Mecoptera, but present in many hemimetabolous insects, implying that the compound eyes of larval Mecoptera are likely homologous with those of hemimetabolous insects. We assume that the peculiar compound eyes of larval Mecoptera are the plesiomorphy of Holometabola, and the stemmata of other holometabolous larvae might be derived from compound eyes.  

Key words: Dicerapanorpa magna, larva, ommatidium, retinula cell, rhabdom, ultrastructure, evolution