Visual Organization and Spectral Sensitivity of Larval Eyes in the Moth Trabala Vishnou Lefebur (Lepidoptera: Lasiocampidae)

青枯葉蛾幼蟲視神經系統之結構與光譜感度

林金盾(Jin-Tun Lin) ； 黃璧祈(Pi-Chi Hwang) ； 童麗珠(Li-Chu Tung)

《Zoological Studies》 41卷4期 (2002/10) Pp. 366-375

摘要

青枯葉蛾（Trabala vishnou Lefebur）的幼蟲在頭部兩側各有六個單眼，每個單眼的大小不同，而基本結構類似小眼，具角膜晶體、角膜生成細胞、圓錐晶體和視細胞等構造。每個單眼均由七個視細胞組成，依其位置歸為遠端和近端兩類，然而排列方式分為兩型：單眼II和V具四個遠端視細胞配三個近端視細胞；其他單眼具三個遠端視細胞配四個近端視細胞。遠端視細胞的桿狀體位於中央，輻射狀排列成星形；近端視細胞桿狀體的排列不規則。各視細胞的基部形成軸突伸出，同側單眼的42條軸突聚成一束單眼視神經，直接投射到腦部視神經叢的特定位置，單眼I- IV投射於前背側，V和VI則較近後腹側。由光譜感度得知單眼I-IV含紫外光、藍光和綠光受器， 而V和VI只有藍光和綠光兩種受器，沒有紫外光受器。

關鍵字

鱗翅目 ； 青枯葉蛾 ； 側單眼 ； 光譜感度

並列摘要

The caterpillar of the moth, Trabala vishnou Lefebur, has 6 stemmata on each side of its head. The diameter of the lens of each stemma varies. However, the basic structure of a stemma is similar to an ommatidium of a compound eye. Each stemma has a corneal lens, corneagenous cells, a crystalline cone, and retinular cells. The 7 retinular cells in each stemma are organized in 2 tiers, distal and proximal. Stemmata II and V both have 4 distal and 3 proximal retinular cells, while the other stemmata have 3 distal and 4 proximal cells in each stemma. The distal rhabdom is star-shaped radially around the central axis of the stemma, and the proximal one is irregular. The proximal part of each retinular cell narrows forming an axon. The 42 axons from the ipsilateral stemmata join together to form an optic nerve which directly enters into the brain. Axons I-IV project anterodorsally to the optic neuropile of the brain, while axons V and VI project posteroventrally. From the spectral sensitivities of stemmata, it is evident that stemmata I-IV have UV, blue, and green receptors, whereas stemmata V and VI have only blue and green units without UV receptors.

並列關鍵字

Lepidoptera ； Trabala vishnou Lefebur ； Stemmata ； Spectral sensitivity