Molecular diet studies of water mites reveal prey biodiversity

has many branches that match the non-biting midge Cricotopus trifasciatus sequence 95% to 98%, the pie chart of sequence abundances for the same specimen (Fig 6A) shows the most common sequence (97% of the sequences) is the one that has a 98% identity to the reference. The pie charts in Fig 6 illustrate diverse diets in Lebertia. These include specimens of the mite L. quinquemaculosa in which most non-mite sequences were from oligochaetes (Fig 6C); another with diverse sources including chironomids, worms, mosquitoes (Culex pipiens, 98.6% identity, 3% of the sequences), and a cladoceran (Chydorus brevilabris, 97.6% identity, 8% of the sequences) (Fig 6D); and another in which the cladoceran Diaphanosoma sp. (96.7% identity) accounted for 46% of the sequences (Fig 6E). Mosquito DNA was found in both mite species L. davidcooki (2 specimens) and L. quinquemaculosa (4 specimens, Figs 6D and 7C). For the seven specimens of L. davidcooki (e.g., Fig 6B) that had Podocopida sp. (with sequence identities ranging from 93 to 96%), this ostracod accounted for a mean of 16% of the sequences. Similarly, in the specimen of the mite Arrenurus, illustrated in Fig 6F, more than 95% of its non-mite sequences were ostracod Podocopida sp. (95.1% identity). Another Dip- teran observed as prey of the mite L. quinquemaculosa was Megaselia sp. with a percent match of 98.5% identity (see Fig 6E). The two species of Lebertia differ in dietary composition and seasonal presence The percent abundances of chironomid, oligochaete, and mosquito sequences in both Lebertia

species are summarized in Fig 7. Chironomids, the most frequently cited prey of Lebertia [8], Fig 6. Abundance of OTUs within representative water mites. (A, B) L. davidcooki; (C-E) L. quinquemaculosa; (F) Arrenurus. Pie sections are proportional to the percent abundance in that mite and labeled with the name of the “best hit” reference sequence, percent identity of the OTU with the reference sequence, and it’s percent abundance. Pie sections with � are OTUs with best matches to a variety of Chironomidae or identified only to that level as the best hit. https://doi.org/10.1371/journal.pone.0254598.g006 PLOS ONE Prey DNA diversity in water mites PLOS ONE | https://doi.org/10.1371/journal.pone.0254598 July 29, 2021 11 / 18