Phytomyxea (plasmodiophorids) is an enigmatic group of obligate biotrophic parasites. Most of the known 41 species are associated with terrestrial and freshwater ecosystems. However, the potential of phytomyxean species to influence marine ecosystems either directly by causing diseases of their hosts or indirectly as vectors of viruses is enormous, although still unexplored. In all, 20% of the currently described phytomyxean species are parasites of some of the key primary producers in the ocean, such as seagrasses, brown algae and diatoms; however, information on their distribution, abundance and biodiversity is either incomplete or lacking. Phytomyxean species influence fitness by altering the metabolism and/or the reproductive success of their hosts. The resulting changes can (1) have an impact on the biodiversity within host populations, and (2) influence microbial food webs because of altered availability of nutrients (e.g. changed metabolic status of host, transfer of organic matter). Also, phytomyxean species may affect their host populations indirectly by transmitting viruses. The majority of the currently known single-stranded RNA marine viruses structurally resemble the viruses transmitted by phytomyxean species to crops in agricultural environments. Here, we explore possible ecological roles of these parasites in marine habitats; however, only the inclusion of Phytomyxea in marine biodiversity studies will allow estimation of the true impact of these species on global primary production in the oceans.

中文翻译：

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寄生植物真菌（疟原虫）在海洋生态系统中的生态作用——综述

Phytomyxea (plasmodiophorids) 是一组神秘的专性生物营养寄生虫。已知的 41 种物种中的大多数与陆地和淡水生态系统有关。然而，植物真菌物种通过直接引起宿主疾病或作为病毒载体间接影响海洋生态系统的潜力是巨大的，尽管仍未得到探索。总的来说，目前描述的 phytomyxean 物种中有 20% 是海洋中一些主要初级生产者的寄生虫，如海草、褐藻和硅藻；然而，关于它们的分布、丰度和生物多样性的信息要么不完整，要么缺乏。Phytomyxean 物种通过改变宿主的新陈代谢和/或繁殖成功来影响健康。由此产生的变化可以 (1) 对寄主种群内的生物多样性产生影响，(2) 影响微生物食物网，因为营养物质的可用性改变（例如宿主的代谢状态改变，有机物质的转移）。此外，植霉菌属物种可能通过传播病毒间接影响其宿主种群。大多数目前已知的单链 RNA 海洋病毒在结构上类似于由植物菌属物种传播到农业环境中的作物的病毒。在这里，我们探索了这些寄生虫在海洋栖息地中可能的生态作用；然而，只有将 Phytomyxea 纳入海洋生物多样性研究，才能估计这些物种对全球海洋初级生产的真实影响。phytomyxean 物种可能通过传播病毒间接影响其宿主种群。大多数目前已知的单链 RNA 海洋病毒在结构上类似于由植物菌属物种传播到农业环境中的作物的病毒。在这里，我们探索了这些寄生虫在海洋栖息地中可能的生态作用；然而，只有将 Phytomyxea 纳入海洋生物多样性研究，才能估计这些物种对全球海洋初级生产的真实影响。phytomyxean 物种可能通过传播病毒间接影响其宿主种群。大多数目前已知的单链 RNA 海洋病毒在结构上类似于由植物菌属物种传播到农业环境中的作物的病毒。在这里，我们探索了这些寄生虫在海洋栖息地中可能的生态作用；然而，只有将 Phytomyxea 纳入海洋生物多样性研究，才能估计这些物种对全球海洋初级生产的真实影响。