How to identify a brown marmorated stink bug

Providing growers methods for identifying this new invasive insect species.

As we move into the 2011 season, growers have two new pests that may appear in their orchards, vineyards and fields. Identifying one of these insects, the brown marmorated stink bug, has been slightly more challenging due to the presence of some native look-alike stink bug species in Michigan. This article is meant to provide growers with simple characteristics that will accurately decipher our native stink bugs with this new invasive pest.

First, all stink bugs are shield-shaped and have long piercing-sucking mouthparts. They also have incomplete metamorphosis, so they have nymphs that resemble the adults except for color and wing length. All stink bugs are aptly named as they emit an odor if disturbed, and the ones found in Michigan are often less than .75 to 1 inch.

The characteristics that sets the brown marmorated stink bug apart from our other sink bugs are

This last trait is important and, unfortunately, difficult to see in the field. We recommend a 30X hand lens to aid in making out the shape of the pronotum; a 14X hand lens will work with good eyes, holding the insect at the correct angle and ample light. All three of these identifiers on one bug are critical for proper identification. Brown marmorated stink bugs are also brown-black in color as adults with a whitish underside. Unfortunately, a few of our other native stink bugs have similar traits. The pictures below should help in differentiating brown marmorated stink bugs from other stinkbug species.

Adult brown marmorated stinkbug with antennal segments highlighted
Adult brown marmorated stinkbug with antennal
segments highlighted. Photo credit: Rutgers University.

Adult rough stinkbug
Adult rough stinkbug, a common look-alike to brown
marmorated stinkbug.
Photo credit: R. Bessin, University of Kentucky.

Close up of brown marmorated stinkbug
Left, a close up of the shield of brown marmorated
stinkbug with a smooth edge. Right, the shield of the
rough stinkbug with a toothed edge.
Photo credit: D. Elsner, MSUE.

Related topic:

If you suspect or see brown marmorated stink bug on your farm or home, please collect specimens and send them to MSU Diagnostic Services:

MSU Diagnostic Services
101 Integrated Plant Systems
East Lansing, MI 48824-1311

Be sure to include a note with your contact information including your email address or phone. Digital photos may be sent to: .(JavaScript must be enabled to view this email address). Please save the specimen after you take the photo for potential further identification.