Water mites (Acari: Hydrachnidiae) are among the most numerous, diverse, ecologically important – and unknown – groups of arthropods in freshwater ecosystems. However, because so little is known about their diversity, water mites are rarely included in freshwater biodiversity inventories, biogeographic studies, assessments of water quality, or evaluations of conservation status. The major factor underlying the neglect of water mites as significant taxa in cross-disciplinary studies is a lack of acarologists trained in modern systematics to provide a greater understanding of the diversity and relationships among taxa.

Water mites are ubiquitous and diverse in freshwater systems, currently with more than 6,000 species, representing more than 400 genera, known worldwide (Di Sabatino et al., 2008). Water mites influence fecundity and survival of insect hosts, and studies on feeding rates indicate that water mites significantly influence the size and structure of host populations (Mullen 1975; Wiles 1982; Smith 1988, 1989; Weiberg and Edwards 1997). Physico-chemical and pollution ecology studies in Europe have also shown that water mites are exceptionally sensitive indicators of habitat quality (Smit and van der Hammen 1992, and Steenbergen 1993). Despite their importance to aquatic communities, most mite species remain unnamed and no comprehensive diagnostic tools exist, rendering the group inaccessible to all but the few specialists. This problem is of great importance because acarology will not progress if hypotheses cannot be tested and continued exclusion of mites from interdisciplinary studies will leave major gaps in our understanding of aquatic systems. Overall, this problem is due to the lack of water mite taxonomists, compounded by the steady loss of experts to retirement. Thus, there is an urgent need to train a new generation of experts and position water mites, and all of acarology, appropriately into the modern systematics world.

Our long-term goal is to train a sufficient number of new water mite systematists and advance the knowledge of diversity to a point where the mites are recognized as integral to interdisciplinary research. The objective of this particular application, which contributes to our long-term goal, is to train two PhD students in water mite systematics using modern taxonomic and phylogenetic methods to revise, monograph, and disseminate data on a North American water mite family, Torrenticolidae. The rationale for the design of this project is to ensure broad training and preparation for the academic world. Additionally, the project will provide the key to future research on commonly collected torrenticolids, by producing a comprehensive monograph and web-based diagnostic tools accessible to all researchers – not solely to specialists. We are well prepared to meet the described need of training the next generation of water mite systematists and successfully completing the proposed systematic work. The assembled team has the range and depth of expertise in water mite systematics to address the problem definitively (see Biographical Sketches). PI Dowling brings a molecular phylogenetic and classical taxonomic background in acarology to the team and PI Radwell provides seven years of water mite taxonomic expertise, knowledge of aquatic ecology, and skills as an educator at all levels. Collaborator Smith has over 40 years of experience in water mite taxonomy, systematics, and ecology, and is committed to pass the requisite skill set and existing knowledge to the next generation of researchers.

We plan to address the current need for new experts by pursuing the following specific aims in the format of a modern monographic project, which will greatly increase the overall knowledge of water mites:

1. Collect and describe North American torrenticolid taxa. Students will participate throughout the monograph process and gain thorough knowledge of field techniques, specimen preparation, character system development, and all aspects of species descriptions, data dissemination, and phylogenetics as described in the aims below.

2. Establish a modern streamlined approach to efficiently describe species and disseminate data through publications and online portals. Based upon preliminary trials, the proposed taxonomic workflow is expected to greatly speed up the time from discovery to publication, immediately increase the web presence of torrenticolids, and produce data accessible and useable across many disciplines.

3. Conduct phylogenetic tests of intrageneric relationships. Students will learn molecular and morphological techniques useful in phylogeny reconstruction. Phylogenies will be directly used to establish a stable classification and test evolutionary hypotheses.

The proposed research representing the first in-depth study of water mite diversity in North America, is expected to yield the following expected outcomes: 1) A comprehensive monograph of North American Torrenticolidae; 2) a streamlined and modern digital approach to taxonomy; 3) interactive tools and information that will establish an online presence for water mite research; and 4) the first phylogenetic tests of North American torrenticolid phylogeny. These outcomes collectively will achieve our goal of training a new generation of water mite systematists with the requisite knowledge and skills to compete in the modern systematics world and push the boundaries of acarological research forward.