Phylogenetic utility and comparative morphology of the composite scale brushes in male phycitine moths (Lepidoptera, Pyralidae)
Zoologischer Anzeiger 248 (2009): 119–136
鱗翅目形態中一般所稱的毛刷 (hair brushes)、毛筆器 (hair pencil)與發香鱗(androconial scales)等特徵，在不同總科類群中多次的出現，其類型與繁複程度、分佈部位皆有所不同，也因而造成此類特徵在命名上的混淆與爭議。
雖然過去不少親緣關係的研究經常選用此類特徵進行形態親緣重建的特徵，然而相較其應用於系統發生學，此類特徵的同源性、組織學與功能形態學的討論顯得少且不完整。
作者Simonsen (註一) 與 Roe是兩位加拿大亞伯達省大學生物科學系的研究員，研究方向著重於鱗翅目螟蛾科類群之系統發生。在此篇文章選用了佔螟蛾科2/3物種數的斑螟亞科(Phycitinae)中的Dioryctria屬(台灣共3種)，來討論高多樣性的第八腹節合生毛刷(composite hair brushes)在超微結構(ultrastructural)、總體形態(gross morphology)與相關且複雜的鄰近腺體組織的同源性，並映像(mapping)此類特徵至Dioryctria屬分子親緣關係樹後，所得到結果的演化意義。
研究方法中，作者使用掃描式電子顯微鏡(SEM)作特徵的觀察與呈現，而非傳統形態所利用的光學或解剖顯微鏡；此外，作者選用了粒線體COI與COII序列，並使用最簡約法(maximum parsimony)進行親緣關係重建，而非一般分子親緣樹重建上所使用的最大概似法(maximum likelihood)或貝葉氏機率(Baysian probability)。
結果方面，作者將此類合生毛叢器特徵再映像至分子樹上，可支持Dioryctria屬的單系性，然而在特徵狀態上具有多次的轉換，也就是屬內特徵狀態具有趨同演化的結果，但當中的樹型分佈卻可支持屬內某些種群(species groups)的單系性。而作者也利用所獲得的結果來闡述結合各種層級特徵的評估可對斑螟亞科的演化關係在未來提供豐富的資訊；最後作者也提到使用掃描式電子顯微鏡而非光學或解剖顯微鏡來分析超微結構，可獲得更多且為3D的立體結構特徵。
註一 Thomas Simonsen的個人介紹
Abstract
Male pyralid moths in the subfamily of Phycitinae are known to possess composite scale brush structures associated with the 8th abdominal sternite, but the histology and the structural morphology of these organs have not been adequately explored. As such, the phylogenetic utility of these structures is unknown. We examine the pre-genitalic abdominal histology of male Dioryctria reniculelloides (Pyralidae: Phycitinae) associated with the composite scale brushes, as well as structural morphology within the genus Dioryctria and two closely related genera. The composite scale brushes are composed of fused scales. The musculature associated with the base of sternum 8 shows considerable modification compared to previously described Lepidoptera. Complex glandular tissue was also found associated with the scale brush structures, suggesting secretory function. Phylogenetic utility of ultrastructure and gross morphology was examined for major Dioryctria species groups. Many characters were homoplasious, but several supported the monophyly of the genus, as well as some internal relationships. In conclusion, the combination of ultrastructural, gross morphological and histological characters can be a rich source of information for elucidating a range of evolutionary relationships within the subfamily.
Keywords: Dioryctria; Phylogeny; Ultrastructure; Histology; Homology
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