台灣產錐蜷科親源關係之研究

Abstract

過去關於台灣錐蜷科（Thiaridae）的分類，目前沒有一個統一的系統，以至於物種在屬級的階層變動頗大，本研究利用外部形態、齒舌、粒線體（16S rRNA gene）等形質建立一套明確分類系統，釐清現今台灣錐蜷科類分類上的問題。 本研究經全島採集調查後，於南台灣七股，首次發現台灣新記錄種，斑蜷（Melanoides maculata）。在形態形質方面，本研究發現，錐蜷科齒舌的小齒數量及形態，可作為物種間的區分依據。而結節蜷本研究並沒有採集到相關的標本，因此本實驗沒有其相關結果。 粒線體16S rRNA基因片段之系統發育樹結果與遺傳距離結果顯示，首先黑蜷的分類地位不屬於錐蜷科，應將其歸於Melanopsidae。其次，結果證明網蜷外殼具有多型性，並且在採集時發現，網蜷與台灣網蜷有共域分布的情形，因此其亞種台灣網蜷的分類位階應以廢除。最後關於流紋蜷在屬階層的異動，本研究結果認為應將其獨立為一個屬Sermyla。本研究結果是，台灣產錐蜷科可以分為5屬8種，第一是Melanoides包含兩個物種，分別是斑蜷M. maculata、網蜷M. tuberculata；第二是Tarebia只有一種瘤蜷Tarebia granifera；第三是Stenomelania有三個物種，分別是細紋蜷S. costellaris、結節蜷S. turulosa與錐蜷S. plicaria；第四是Thiara 只有一種塔蜷T. scabra；第五是Sermyla 只有一種流紋蜷Se. riqueti。In past reserch history, the classification on family Thiaridae went through several huge change. This research uses three important attributions of Mollusc, the external form, radula and mitochondria 16S rRNA, in order to establish an unequivocal phylogenetic tree. By using this result, to solve many doubts while distinguishing between family Thiaridae in Taiwan. This research has not been gathered Stenomelania torulosa and Faunus ater, so we don’t have any results about them. And this research discovered that the character of form and numbers of caps can be use to species identification. According to the analysis of mitchondria 16S rRNA partial gene fragments, this study results do not support F. ater as Thiaridae, should belong to it Melanopsidae, and support riqueti independent to the genus Sermyla, and we can prove Melanoides tuberculata shells have many types, M. tuberculata formosanus of Thiaridae that the classification level can be abolished becouse M. tuberculata and M. tuberculata formosanus, these two kinds, is distributed in the land altogether. This study got the following results, Taiwan Thiaridae can be divided into 5 genera and 8 species, there are M. tuberculata, M. maculata, S. riqueti, S. costellaris, S. plicaria, S. torulosa, Tarebia granifera, and Thiara scabra.