Ground Beetles (Carabidae)

Containing some of the most colorful beetles found on Martha’s Vineyard, as well as a few of the most conspicuous ones, the family Carabidae is a large one; bugguide.net reports about 34,000 species worldwide and almost 2,500 species in North America. Members of the family vary widely in appearance, though the typical appearance of ground beetles includes broad elytra and a smaller thorax and head. Some species are iridescent or brightly colored, and many have striations or other texture on their elytra. As the family’s common name suggests, many members are usually found on the ground, some of them pursuing prey in the open, some of the lurking beneath leaf litter, fallen logs, or bark. Other Carabids, though, turn up on flowers or a range of other substrates, and it is worth remembering that generally these beetles are active and mobile: they are often found in unexpected places. As a group, Carabids tend to be largely or exclusively nocturnal, and it worth mentioning that many of the Vineyard’s records for beetles in this family come from moth sheets, where ultraviolet lights attract a range of nocturnal arthropods.

While some taxonomies consider tiger beetles to be a subfamily of Carabidae (Cicindelinae), we follow iNaturalist and most contemporary taxonomies in affording the tiger beetles full family status. So the Vineyard’s dozen or so tiger beetle species have their own checklist and do not appear in this section.

For a group of beetles that are on average fairly large and may have prominent colors or color patterns, Carabid beetles are surprisingy difficult to identify. A high percentage of the Vineyard’s iNaturalist observations of this family have not been identified to species, and in many cases even the genus is not yet confirmed. In assembling this checklist, we’ve taken a conservative stance, relying on two main sources. Some species are included here on the basis of one or more “research-grade” observation in iNaturalist. We are also extremely grateful to The Nature Conservancy of Massachusetts, which kindly gave us access to an unpublished report (Purrington 1997) compiled by the late entomologist Foster Forbes Purrington, who carried out extensive Carabid surveys on Martha’s Vineyard, Nantucket, and Tuckernuck for the Conservancy in the mid-1990s. The “Comments” column of the accompanying checklist notes the basis for inclusion of each species, with “iNat” indicating iNaturalist and “FFP” indicating the Purrington report. Courtesy of The Nature Conservancy of Massachusetts, we are making two of Dr. Purrington’s reports available via links in the sidebar on this page. One of these is the aforementioned Vineyard report (Purrington 1997). The other is a report on even more extensive survey work on Nantucket, included here as valuable resource for the regional insect fauna of the Massachusetts islands. Both of these documents are scans, in .PDF format, of the original hard copy reports prepared by Dr. Purrington for the Conservancy.

In all, our checklist includes a total of 70 Carabid species known from Martha’s Vineyard. It is of course very possible that other species remain to be discovered here, or that species documented by Purrington have been extirpated by one cause or another in the 30 years since his surveys were conducted. So, as with other taxonomic groups, further work, whether casual observation or formal studies, is heartily encouraged.

Matt Pelikan, September 10, 2026