The genus Amphidinium is an important group of athecated dinoflagellates because of its high abundance in marine habitats, its member’s ability to live in a variety of environmental conditions and ability to produce toxins. Furthermore, the genus is of particular interest in the biotechnology field for its potential in the pharmaceutical arena. Taxonomically the there is a history of complication and confusion over the proper identities and placements of Amphidinium species due to high genetic variability coupled with high morphological conservation. Thirteen years has passed since the most recent review of the group, and while many issues were resolved, some remain. The present study used microscopy, phylogenetics of the 28S region of rDNA, secondary structure of the ITS2 region of rDNA, compensatory base change data, and cytotoxicity data from Amphidinium strains collected world-wide to elucidate remaining confusion. This holistic approach using multiple lines of evidence resulted in a more comprehensive understanding of the morphological, ecological, and genetic characteristics that are attributed to organisms belonging to Amphidinium, including six novel species: A. fijiensis, A. magnum, A. paucianulatum, A. pseudomassartii, A. theodori, and A. tomasii.

两栖动物属是一类重要的无鞭毛鞭毛动物，因为它在海洋生境中的丰度很高，其成员在各种环境条件下的生活能力和产生毒素的能力。此外，由于其在制药领域的潜力，该属在生物技术领域特别受关注。从分类学上讲，对两栖动物的正确身份和位置有复杂和困惑的历史物种由于高的遗传变异性和高度的形态保存。自小组最近一次审核以来已经过去了十三年，尽管许多问题得到解决，但仍有一些问题。本研究使用显微镜技术，rDNA的28S区系统发育，rDNA的ITS2区的二级结构，代偿性碱基变化数据以及从全球范围内收集的两性双歧杆菌菌株的细胞毒性数据来阐明仍然存在的混淆。这种使用多种证据的整体方法导致对形态，生态和遗传特征的更全面理解，而形态，生态和遗传特征归因于属于两栖动物的生物，包括六个新物种：A。fijiensis，一。大酒瓶，一。paucianulatum，一。pseudomassartii，一。theodori，和一个。托马西。