First insight into molecular diversity of interstitial water mites (Acari: Hydrachnidia): a case study from the upper Neretva River in Bosnia and Herzegovina

ABSTRACT

Water mites are a diverse but neglected meiofaunal group in interstitial habitats. In this study, water mites were sampled from the hyporheic zone of the upper Neretva river catchment in Bosnia and Herzegovina. In total, 10 obligate subterranean (hyporheobiontic) species were detected. Seven of them, i.e. Atractidespumilus (Szalay, 1946), Frontipodopsis reticulatifrons Szalay, 1945, Lethaxona pygmaea K. Viets, 1932, Paraxonopsis inferorum (Motaş and Tanasachi, 1947), P. vietsi (Motaş and Tanasachi, 1947), Erebaxonopsis brevipes Motaş and Tanasachi, 1947, and one halacarid species, Parasoldanellonyx typhlops K. Viets, 1933, were recorded for the first time for the fauna of Bosnia and Herzegovina. The first DNA barcoding data are provided for three families (Frontipodopsidae, Lethaxonidae, and Hungarohydracaridae), one subfamily (Stygomomoniinae), and 10 species, providing the first basis for a DNA barcode reference library of water mites from the interstitial habitats in South-Eastern Europe. In each of the four species, considered to have a wide Western Palaearctic distribution, i.e., A. pumilus, F. reticulatifrons, Hungarohydracarus subterraneaus, and Stygomomonia latipes, two separate lineages were distinguished. Fossil-calibrated modelling revealed that the diversification and speciation processes within the above-mentioned species started in the Late Miocene (7.3–11.8 Ma).

KEYWORDS:

• Water mites
• DNA-barcoding
• hyporheic zone
• Balkans
• hyporheobiontic species

Acknowledgments

Special thanks to Harry Smit (Alkmaar) whose constructive comments greatly improved this paper. We are indebted to the organizing team of Neretva Science Week for offering the opportunity to study the subterranean fauna. We thank Vojo Milanović and Stefan Andjus for their help with field work, and Gregor Bračko, Annasibila Požrl and Lan Glad Zidar for their help with sorting of the collected material. BR, ŠB, EP, and MZ work was supported by Riverwatch and the organizers of the “Neretva Science Week 2022” and partly by Slovenian Research Agency through core funding P1-0184 and PhD grant to EP. EP was also supported by the University Foundation of eng. Milan Lenarčič. MZ was partly supported by Biodiversa+, the European Biodiversity Partnership under the 2021-2022 BiodivProtect joint call for research proposals, co-funded by the European Commission (GA N°101052342) and with the funding organisations Ministry of Universities and Research (Italy), Agencia Estatal de Investigación – Fundación Biodiversidad (Spain), Fundo Regional para a Ciência e Tecnologia (Portugal), Suomen Akatemia – Ministry of the Environment (Finland), Belgian Science Policy Office (Belgium), Agence Nationale de la Recherche (France), Deutsche Forschungsgemeinschaft e.V. (Germany), Schweizerischer Nationalfonds (Grant N° 31BD30_209583, Switzerland), Fonds zur Förderung der Wissenschaftlichen Forschung (Austria), Ministry of Higher Education, Science and Innovation (Slovenia), and the Executive Agency for Higher Education, Research, Development and Innovation Funding (Romania). This study is part of the “DNA-Eco” scientific project, supported by a grant of the Montenegrin Ministry of Science. We thank two anonymous reviewers, whose constructive comments greatly improved this work.

Disclosure statement

No potential conflict of interest was reported by the author(s).