The benthic biome of the deep‐sea floor, one of the largest biomes on Earth, is dominated by diverse and highly productive heterotrophic protists, second only to prokaryotes in terms of biomass. Recent evidence suggests that these protists play a significant role in ocean biogeochemistry, representing an untapped source of knowledge. DNA metabarcoding and environmental sample sequencing have revealed that deep‐sea abyssal protists exhibit high levels of specificity and diversity across local regions. This review aims to provide a comprehensive summary of the known heterotrophic protists from the deep‐sea floor, their geographic distribution, and their interactions in terms of parasitism and predation. We offer an overview of the most abundant groups and discuss their potential ecological roles. We argue that the exploration of the biodiversity and species‐specific features of these protists should be integrated into broader deep‐sea research and assessments of how benthic biomes may respond to future environmental changes.

中文翻译：

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凝视深渊：一睹深海海底异养原生生物的多样性、分布和行为

深海海底生物群落是地球上最大的生物群落之一，以多样化且高产的异养原生生物为主，其生物量仅次于原核生物。最近的证据表明，这些原生生物在海洋生物地球化学中发挥着重要作用，代表着未开发的知识来源。DNA 元条形码和环境样本测序表明，深海深海原生生物在局部区域表现出高水平的特异性和多样性。本综述旨在全面总结深海海底已知的异养原生生物、它们的地理分布以及它们在寄生和捕食方面的相互作用。我们概述了最丰富的群体，并讨论了它们潜在的生态作用。我们认为，对这些原生生物的生物多样性和物种特异性特征的探索应该纳入更广泛的深海研究和评估中，以了解海底生物群落如何应对未来的环境变化。