Cryophilic Tardigrada have disjunct and bipolar distribution and establish long-term stable, low-density demes

0576048 - ÚŽFG 2024 RIV DE eng J - Journal Article
Zawierucha, K. - Štefková Kašparová, Eva - McInnes, S. - Buda, J. - Ambrosini, R. - Devetter, Miloslav - Ficetola, G. F. - Franzetti, A. - Takeuchi, N. - Horna, Patrik - Novotná Jaroměřská, T. - Ono, M. - Šabacká, M. - Janko, Karel
Cryophilic Tardigrada have disjunct and bipolar distribution and establish long-term stable, low-density demes.
Polar Biology. Roč. 46, č. 10 (2023), s. 1011-1027. ISSN 0722-4060. E-ISSN 1432-2056
R&D Projects: GA ČR(CZ) GA22-28778S; GA MŠMT(CZ) EF18_053/0017247; GA MŠMT EF15_003/0000460
Institutional support: RVO:67985904 ; RVO:60077344
Keywords : Long-range dispersal * Disjunct distribution * Glaciers * Cryoconite holes * Biogeography * Tardigrada
OECD category: Biology (theoretical, mathematical, thermal, cryobiology, biological rhythm), Evolutionary biology; Zoology (BC-A)
Impact factor: 1.7, year: 2022
Method of publishing: Open access
https://link.springer.com/article/10.1007/s00300-023-03170-4

Glaciers are inhabited by various cryophilic organisms ranging from single celled to multicellular, like Tardigrada (water bears). Owing to their scattered distribution, glaciers represent extremely fragmented habitats, and it remains unclear how their inhabitants survive and disperse among such isolated patches. This study investigates the biogeography of the tardigrade genus Cryoconicus, whose distribution, population stability, and interregional connectivity are examined by screening the collections from similar to 60 glaciers worldwide and by a phylogeographic analysis. We found that two Cryoconicus species occur at low densities on two Arctic glaciers in Svalbard, far from their previously reported Antarctic and Central Asian ranges. Screening of worldwide databases and DNA metabarcoding indicated that these species are absent or rare in the intermediate areas, suggesting large disjunctions in their ranges. In particular, the genetic data and multiyear resampling showed that Cryoconicus kaczmareki established a stable population on the Ebba Glacier (Svalbard), which has been isolated from its Asian core range since before the last glacial maximum. Our findings suggest that glacial invertebrates may possess wide yet largely disjunctive ranges. Interpolar- or intercontinental-scale movements of cryophilic meiofauna may occur, but migration connectivity is not sufficient to mitigate the differentiation of the local population. Revealed biogeographic patterns further demonstrate that inhabitants of extreme environments may establish isolated and highly fragmented populations that persist long term, even if at very low densities.
Permanent Link: https://hdl.handle.net/11104/0345936