摘要
Alexandrium catenella (Whedon et Kof.) Balech, A. tamarense (M. Lebour) Balech, and A. fundyense Balech comprise the A. tamarense complex, dinoflagellates responsible for paralytic shellfish poisoning worldwide. The relationships among these morphologically defined species are poorly understood, as are the reasons for increases in range and bloom occurrence observed over several decades. This study combines existing data with new ribosomal DNA sequences from strains originating from the six temperate continents to reconstruct the biogeography of the complex and explore the origins of new populations. The morphospecies are examined under the criteria of phylogenetic, biological, and morphological species concepts and do not to satisfy the requirements of any definition. It is recommended that use of the morphospecies appellations within this complex be discontinued as they imply erroneous relationships among morphological variants. Instead, five groups (probably cryptic species) are identified within the complex that are supported on the basis of large genetic distances, 100% bootstrap values, toxicity, and mating compatibility. Every isolate of three of the groups that has been tested is nontoxic, whereas every isolate of the remaining two groups is toxic. These phylogenetic groups were previously identified within the A. tamarense complex and given geographic designations that reflected the origins of known isolates. For at least two groups, the geographically based names are not indicative of the range occupied by members of each group. Therefore, we recommend a simple group-numbering scheme for use until the taxonomy of this group is reevaluated and new species are proposed.
摘要译文
链状亚历山大藻（温登等拳皇）Balech，A.藻（M. Lebour）Balech和A. fundyense Balech包括A.藻复杂，甲藻负责全球麻痹性贝类中毒。这些形态定义物种之间的关系知之甚少，作为的原因是增加的范围和华发生观察了几十年。INES从株六温带大陆发起新的核糖体DNA序列，现有的数据来重建复杂的生物地理学和探索新的人群的起源。的形态种被检查下的系统发育，生物和形态学物种概念的标准，并且不以满足任何定义的要求。建议在这个复杂的内部使用的形态种称谓，因为他们暗示形态之中变种错误的关系终止。相反，五组（可能是隐种）标识被大量遗传距离，100％的自举值，毒性和交配兼容性的基础上支持的配合物中。每隔离3已测试是无毒的基团的，而每一个隔离剩余的两个基团是有毒的。这些亲缘团体先前的A.内确定藻复杂和特定地理名称反映称分离的起源。用于至少两个基团，在基于地理位置的名称不表示由每组的成员所占据的范围之外。因此，我们推荐一个简单的组编号方案的使用，直到这个群体的分类被重新评估，新品种提出了建议。
Emily L. Lilly[1,‡]; Kenneth M. Halanych[2] and Donald M. Anderson[3];. Species boundaries and global biogeography of the Alexandrium tamarense complex (Dinophyceae)1[J]. Journal of Phycology, 2007,43(6): 1329-1338