华山松大小蠹成虫复眼的外部形态及显微结构

External morphology and microstructure of compound eyes of adult Dendroctonus armandi Tsai et Li(Coleoptera:Scolytidae)

【目的】对华山松大小蠹雌雄成虫复眼的外部形态和内部结构进行研究，为进一步探索华山松大小蠹感光和光选择机制提供理论基础。【方法】应用扫描电镜与透射电镜对华山松大小蠹复眼的形态结构进行观察。【结果】华山松大小蠹复眼呈长椭圆形，位于头部两侧；眼表面光滑平坦，小眼间隙被覆有感觉毛。华山松大小蠹雌、雄成虫复眼的小眼组成数目分别为238～250和187～202；雌性小眼间隙着生有角膜乳突；复眼中心区域小眼呈正六边形，边缘区域的小眼为不规则的四边形或六边形。华山松大小蠹成虫复眼具有典型的无晶锥并列像眼。华山松大小蠹成虫复眼由1个角膜、1个晶锥体、2个初级色素细胞、8个小网膜细胞和其特化的视杆、若干个次级色素细胞和基膜构成。视杆属于半集中型视杆。【结论】华山松大小蠹雌雄成虫复眼具有相同的内部结构，但雌性成虫复眼分辨能力和可见距离稍优于雄性成虫。

[Objective] The external morphology and internal microstructure of compound eyes of Den- droctonus armandi Tsai et Li were observed to provide reference for studying the photoreception and light- selection mechanism. [Method] The morphological structure of adult D. arrnandi was observed using scan- ning electron microscope （SEM） and transmission electron microscope （TEM）. [Result] The compound eyes of adult D. arrnandi were long ovals located on the lateral upside of head. The surface of the omma- tidia was smooth and covered with interommatidial hairs. The compound eyes of female and male of D. ar- mandi consisted of roughly 238-- 250 and 187-- 202 ommatidias, respectively. The interommatidial of female ommatidias was covered with corneal nipples. The ommatidias located in the central region of the compound eyes were typically hexagonal, while those located in the periphery of the compound eyes were often irregu- lar,or in pentagonal and hexagonal shapes. The organization of compound eyes of D. arrnandi was typical cone apposition eyes. The ommatidium of compound eyes of D. armandi consisted of a cornea,a crystalline cone,two primary pigment cells, eight retinal cells and rhabdom,a number of secondary pigment cells and basement membrane. The rhabdom was intermediate between ＂open＂ and ＂fused＂ rhabdomeric arrange- ments of rhabdom. [Conclusion] Although male and female adults had the same structure, the resolvingpower and visibility of female were better.