Systematic revision of Symbiodiniaceae highlights the antiquity and diversity of coral endosymbionts

The advent of molecular data has transformed the science of organizing and studying life on Earth. Genetics-based evidence provides fundamental insights into the diversity, ecology, and origins of many biological systems, including the mutualisms between metazoan hosts and their micro-algal partners. A well-known example is the dinoflagellate endosymbionts (“zooxanthellae”) that power the growth of stony corals and coral reef ecosystems. Once assumed to encompass a single panmictic species, genetic evidence has revealed a divergent and rich diversity within the zooxanthella genus Symbiodinium. Despite decades of reporting on the significance of this diversity, the formal systematics of these eukaryotic microbes have not kept pace, and a major revision is long overdue. With the consideration of molecular, morphological, physiological, and ecological data, we propose that evolutionarily divergent Symbiodinium “clades” are equivalent to genera in the family Symbiodiniaceae, and we provide ...分子数据的问世彻底革新了地球生命分类与研究的科学范式。基于遗传学的证据为诸多生物系统的多样性、生态学特征与起源提供了基础性认知，涵盖后生动物（metazoan）宿主与其微藻共生伙伴之间的共生关系。其中一个广为人知的案例便是甲藻（dinoflagellate）内生共生体（zooxanthellae，又称虫黄藻）——它们为石珊瑚及珊瑚礁生态系统的生长提供核心动力。此前学界曾假定虫黄藻属（Symbiodinium）仅包含一个泛交的单一物种，但遗传学证据却揭示了该属内存在丰富且分化显著的类群多样性。尽管数十年来学界已多次报道该多样性的重要意义，但这些真核微生物的正式分类系统却未能与时俱进，大幅修订早已迫在眉睫。综合分子、形态学、生理学与生态学数据，我们提出：演化上分化显著的Symbiodinium"演化支（clades）"应等同于共生甲藻科（Symbiodiniaceae）下的属级分类单元，且我们将提供……