由功能形態與演化學來探討鱗翅目成蟲之口器取食機制

文獻出處: Krenn, H. W. 2010. Feeding mechanism of adult Lepidoptera: Structure, Function, and Evolution of the Mouthparts. Ann. Rev. Entomol. 55: 307-327.

[Abstract]

簡介
由於為數龐大的鱗翅目類群在幼蟲時期取食植物而於成蟲訪花吸食花蜜，所以被認為在口器形態的演化與維管束植物有長久密切的關連，而鱗翅目成蟲口器的形態在過去訪花昆蟲分類群之中的研究也所佔多數，且可分為解剖學、功能形態學、生態學與演化學來進行討論。本文即為介紹並回顧鱗翅目成蟲口器的研究發展。

文章主要分為三大主題:

1. 鱗翅目口器型式的形態與演化: 介紹並圖解由小蛾科、食杉蛾科與異石蛾科等基群(basal lineage)成蟲的咀嚼式口器，演化至具有管狀可曲捲吸食花蜜或水溶液的旋喙群(glossata)成蟲的虹吸式口器，其不同部位口器結構(如大小顎與下唇)的形態改變。
2. 旋喙群管狀口器的運動與液體吸取方式: 由功能形態學介紹管狀口器伸展的肌肉控制與藉由虹吸幫浦(sucking pump)產生液體壓力梯度來吸取不連續流質液體的步驟過程。
3. 旋喙群對不同食物資源的口器演化與其形態多樣性: 介紹利用不同食物資源的具管狀口器鱗翅目，例如吸花蜜、吸哺乳動物淚液、吸表面水溶液或是刺吸水果果肉汁液等，其演化出的特殊口喙結構與相關行為來達成食物的最有效利用。

對於原文章所討論的鱗翅目分類群科名可參見昆蟲綱科以上學名中名對照表, 相關文章可點閱:

• 蝴蝶喝珍奶，奶茶哪裡來?
• 全球壺夜蛾族物種名錄

Abstract

The form and function of the mouthparts in adult Lepidoptera and their feeding behavior are reviewed from evolutionary and ecological points of view. The formation of the suctorial proboscis encompasses a fluid-tight food tube, special linking structures, modified sensory equipment, and novel intrinsic musculature. The evolution of these functionally important traits can be reconstructed within the Lepidoptera. The proboscis movements are explained by a hydraulic mechanism for uncoiling, whereas recoiling is governed by the intrinsic proboscis musculature and the cuticular elasticity. Fluid uptake is accomplished by the action of the cranial sucking pump, which enables uptake of a wide range of fluid quantities from different food sources. Nectar-feeding species exhibit stereotypical proboscis movements during flower handling. Behavioral modifications and derived proboscis morphology are often associated with specialized feeding preferences or an obligatory switch to alternative food sources.