A DNA barcoding and photo-documentation resource of water mites (Acariformes, Hydrachnidia) of Siberia: Accurate species identification for global climate change monitoring programs

Abstract

Water mites (Hydrachnidia) are good model organisms for the assessment and long-term monitoring of the biological impacts of natural and human-induced environmental changes in freshwater ecosystems, including those related to global climate change. However, monitoring programs using water mites as bioindicators may be impeded by difficulties associated with species identification. Here we integrate conventional morphology, DNA sequence data (using the COX1 barcoding locus) and extensive voucher photo documentation to create and validate a tool for accurate species identification of water mites in Western Siberia (including a dedicated reference climate monitoring and research site). Using this approach, we detected a total of 95 species, of which, one was a conventional new species; 14 taxa were cryptic species having large among-species COX1 K2P distances but lacking any apparent morphological differences. Our a priori species delimitation was successfully validated a posteriori. An automatic species delimitation algorithm (ASAP) identified exactly the same set of 95 species, with a species delimitation threshold of 6.1%. This result agrees with previous works suggesting a large threshold of 5.6–6.0% for water mites, but contrasts with the BOLD approach which uses a much lower threshold to identify BINs (1%). Furthermore, by comparing our identified sequences with GenBank data, we expanded known geographic ranges of several water mite species. Using extensive GenBank data on mites in Canadian waters, four species were detected to be Holarctic rather than Palaearctic as thought previously (Lebertia obscura, Limnesia undulatoides, Oxus nodigerus and Arrenurus papillator). Four species, Lebertia obscura, Torrenticola brevirostris, Hygrobates limnocrenicus and Unionicola parvipora, were recorded for the first time in Russia. We provide an annotated species checklist reporting the distribution, ecology, bioindiocation potential, and COX1 barcode sequence data along with high-resolution photographs of each DNA voucher. Future ecological and biodiversity studies will benefit from using molecular tools for accurate identification of useful mesofaunal bioindicator organisms, such as water mites.

Molecular diversity and species delimitation in the genus Mideopsis Neuman, 1880 in Europe (Acari, Hydrachnidia, Mideopsidae)

“…Guo & Kong 2022;Yin et al 2023) is more conservative and is probably the best species-delimitation model for water mites. This is consistent with the previous studies on water mites in which the delimitation approach was used (e.g., Klimov et al 2022;Tyukosova et al 2022;Pešić et al 2023a, b;Pešić & Smit 2023;Pešić & Goldschmidt 2023) which indicates that the use of methods such as ASAP in combination with morphological data can be considered a successful tool for species delimitation in water mites. Our molecular analysis reveals that specimens from Central and Northern Europe, which were often attributed to widely distributed M. orbicularis, morphologically, due to a flattened dorsal shield, belong to two well-defined clades with a high COI divergence.…”

“…DNA was extracted from 26 specimens of the genus Mideopsis listed in Table 1. For all other species (Arabi et al 2012;Macher et al 2020, Pešić et al 2021a, b, 2022aPešić & Smit 2022;Klimov et al 2022), 45 COI additional sequences were retrieved from the respective sequence data archives. Relevant voucher information, photos, and newly generated DNA barcodes are publicly accessible through the dataset DS-MIDHYD in BOLD.…”

Two new species and a new synonym of Eustigmaeus (Acari: Stigmaeidae) from Russia with COI barcode

“…DNA extraction, oligonucleotide primers, amplification and sequencing have been done following Klimov and OConnor (2008), Matthews et al (2018), Klimov et al (2022). The sequences are deposited in the GenBank under the accession No.…”

A new species of Postumius (Acari: Stigmaeidae) from Asian Russia with COI barcode

“…A fragment of the COI barcoding gene (799 bp) had been sequenced from a single mite specimen from Buryatia. DNA extraction, oligonucleotide primers, amplification, and sequencing as described in Klimov & OConnor (2008), Matthews et al (2018), Klimov et al (2022). The sequence is deposited in GenBank under accession no.…”