Advances in tardigrade diversity, distribution characteristics and ecological functions

doi:10.17520/biods.2024406

Abstract

Abstract:

Background: Tardigrades, commonly known as water bears, are microscopic invertebrates inhabiting diverse environments across marine, freshwater, and terrestrial ecosystems. As essential components of microfauna communities, they are renowned for their extraordinary extremotolerant adaptability and occupy multiple trophic levels within micro-food webs, indicating their significant ecological roles. Despite significant advancements made in understanding tardigrade biodiversity, identification methodologies, physiological and ecological traits recently, a comprehensive summaries remains lacking.

Bibliometric analyses & Perspective: Through bibliometric analyses of global tardigrade research over the past three decades, this review systematically summarizes the research progress in the new species discovery, identification methods, distribution characteristics, and ecological functions of tardigrades. The primary findings encompass: (1) Up to 2024, 1,488 documented tardigrade species inhabit a wide range of aquatic and terrestrial ecosystems, including moss, soil, marine environments, polar regions, and even anthropogenic habitats, with new species being continuously discovered. (2) Current identification methods remain predominantly morphology-based, while standardized molecular tools for phylogenetic resolution are critically underdeveloped, severely constrain taxonomic advancements. (3) We describe characteristics in aquatic ecosystems and unique adaptive mechanisms to global change stressors including climate warming and atmospheric nitrogen deposition. (4) Preliminary summaries reveal their ecological roles in micro-food webs through interactions with meiofauna and microbial communities.

Future prospects: We propose three critical research priorities: (1) Emphasizing the need to improve molecular biology research methods; (2) Exploring the distribution characteristics across different ecosystems on large spatial and long-term temporal scales; (3) Elucidating their position in micro-food webs and ecological functions.

Key words: tardigrade, distribution characteristics, ecological function, food web, bibliometric analyses

Chen Dingsong, Liu Zikai, He Ziyang, Chen Weidong. Advances in tardigrade diversity, distribution characteristics and ecological functions[J]. Biodiv Sci, 2025, 33(2): 24406.

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URL: https://www.biodiversity-science.net/EN/10.17520/biods.2024406

https://www.biodiversity-science.net/EN/Y2025/V33/I2/24406

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