Methods

Michigan Coleoptera records were extracted from over 600 publications dating from 1850 to 2020 (see Reference tab for the ones cited in the species lists).  Much of the relevant literature was found in sources cited in American Beetles (Arnett and Thomas 2001, Arnett et al. 2002), Downie and Arnett (1996), and on the BugGuide website.  Original descriptions were checked in some cases to verify a Michigan record, especially for species not reported in the past 100 years.

Online searches were also conducted on Google Scholar for all beetle families. We also reviewed titles and tables of contents of several publications searching for additional records, including every issue of The Great Lakes Entomologist and its predecessor The Michigan Entomologist (1966-2020), the Newsletter of the Michigan Entomological Society (1956-2020), and The Coleopterists Bulletin, beginning from 1975.  We also looked at the titles of every contribution in every issue of the publications Insecta Mundi, ZooTaxa, and ZooKeys from their inception of publication to mid-2020.  Any title that looked promising was downloaded and searched for Michigan records.  We also searched the online website SCAN (Symbiota Collections of Arthropods Network; https://scan-bugs.org/) for beetle species reported to have been collected in Michigan and were housed at any of the participating major insect collections in North America.

Sources in all upper-case letters refer to specific insect collections, e.g., MSU-ARC refers to material held by the Michigan State University Arthropod Research Collection (data provided by G. Parsons), while all others refer to collection data extracted from SCAN (see abbreviations below). Initially, we recorded the literature or collection source where each species was mentioned and the scientific name that was used by that source.  All data were entered into an Excel file. Next, each scientific name was checked to determine whether it is still valid or if it had been synonymized under another name. Identifications were then verified (or corrected as necessary) for species records from the MSU collection that did not appear in the literature or for which there was no modern record. This step is still ongoing.

        The final step was to select up to five sources for each species to justify its inclusion in our list of Michigan beetles.  When fewer than five sources were found, we included every source.  In other cases, over 10 sources were known, so we chose a representative group of older and newer ones, but always included MSU-ARC if they had specimens.

Species names preceded by a single '?' are considered probable (for occurring in Michigan) but uncertain records. Those preceded by '??' are considered possible but unlikely to occur in Michigan. Species that are fully accepted as having valid Michigan records are unmarked. These designations appear only in the species lists for each family; they are not included in the species index. At the end of each family, we list those species reported in the literature that we consider to be erroneous Michigan records.

In general, we followed Bouchard et al. (2011) subfamily and tribe taxonomic rankings.  However, there were some exceptions as explained under the Taxonomic Notes tab. For each species the scientific name and authority are given followed by one or more sources that report the species as occurring in Michigan.

        The following abbreviations are used to indicate insect collections that are reported to contain specimens collected in Michigan and that we cite in our list: