Introduction. The name of each listed species is followed by up to five sources that report the species as occurring in Michigan. Sources in all upper-case letters refer to specific insect collections: MSU-ARC refers to material held by the Michigan State University Arthropod Research Collection (data provided by G. Parsons). All others refer to collection data extracted from the Symbiota Collections of Arthropods Network (SCAN) database online at https://scan-bugs.org/. See the Methods page for a list of abbreviations and associated collections.

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. Species reported in the literature that we consider to be erroneous Michigan records are in a separate list following the others.

We thank T. C. McElrath of the Illinois Natural History Survey for assistance with several identifications. An excellent webite is available for this family at http://monotomidae.com/index.html.

MONOTOMIDAE

2 subfamilies, 2 tribes, 4 genera, 12 species

Subfamily Monotominae

Tribe Europini

Bactridium ephippigerum (Guérin-Méneville, 1837): Hubbard and Schwarz (1878), MSU-ARC

Bactridium striolatum Reitter, 1872: Hubbard and Schwarz (1878), Leng (1920), Casey (1916), Downie and Arnett (1996), MSU-ARC; B. convexulum was described based on a male from Michigan (now a synonym of striolatum)

Pycnotomina cavicolle (Horn, 1879): MSU-ARC, GMNH:UGCA; ID of MSU specimen by T. McElrath

Tribe Monotomini

Monotoma americana Aubé, 1837: Hubbard and Schwarz (1878), MSU-ARC

Monotoma bicolor Villa & Villa, 1835: Bousquet and Laplante (1999), Hubbard and Schwarz (1878), Downie and Arnett (1996), MSU-ARC

Monotoma myrmecophila Bousquet & Laplante, 2000: Bousquet and Laplante (1999)

Monotoma picipes Herbst, 1793: Bousquet and Laplante (1999), Hubbard and Schwarz (1878), MSU-ARC

Subfamily Rhizophaginae

Rhizophagus brunneus brunneus Horn, 1879: Bousquet (1990), Andrews (1923), Hubbard and Schwarz (1878), Downie and Arnett (1996), MSU-ARC

Rhizophagus dimidiatus Mannerheim, 1843: Bousquet (1990)

??Rhizophagus pusillus Bousquet, 1990: Bousquet (1990); "The record from Michigan may not be reliable." Bousquet (1990)

Rhizophagus remotus LeConte, 1866: Bousquet (1990), Downie and Arnett (1996), MSU-ARC

Rhizophagus sayi Schaeffer, 1913: Bousquet (1990), Hubbard and Schwarz (1878), Townsend (1889), MSU-ARC

The following species was also reported from Michigan, but we consider it to be adventive, a misidentification or other error:

Subfamily Rhizophaginae

Rhizophagus minutus Mannerheim, 1853: Downie and Arnett (1996), Leng (1920); the eastern subspecies (newly described in 1990 by Bousquet) is known no closer than 200 miles from MI.

This family list was last updated: February 3, 2023