Stink Bugs and Similar-Appearing Insects in Iowa

The brown marmorated stink bug (BMSB) is a recently-introduced, invasive insect now found throughout the U.S. Several native or established insects in Iowa are similar in appearance to the BMSB. See the photos below to determine if you have BMSB in your home, landscape or field. Submit all suspect specimens to clinic (at no charge) by following the steps for Submitting an Insect Specimen.

Stink bugs and similar-appearing insects

Brown marmorated stink bug
Brown marmorated stink bug.

Brown Marmorated Stink Bug

  • approximately 5/8 inch long
  • a mottled brownish grey color
  • "shield" shaped body
  • antennae with alternating light and dark bands
  • top of the abdominal segments protruding from beneath the wings with alternating dark and light bands.
  • underside is pale in color


Brown Stink Bug

  • About 0.5 inch long
  • shield-shaped
  • grayish-yellow with dark punctures on the back
  • fourth and fifth antennal segments darker in color
  • front corners of thorax rounded to slightly pointed
  • underside with a pinkish tinge

Spined Soldier Bug

Spined soldier bug
Spined soldier bugs eating a lady beetle larva.
  • About 0.5 inch long, but variable
  • Color varies from yellowish to pale brown
  • small black specks cover the back
  • acute spines on the front corners of the thorax
  • a short black line on the wing tips which extends beyond the abdomen
  • the conspicuous spine on the middle of the front tibia may be noticeable
Image of a pine seed bug.
Western pine seed bug.

Western Pine Seed Bug

  • A common household accidental invader in Iowa
  • about 1 inch long
  • elongate in shape
  • dull reddish brown in color
  • pointed at both ends
  • antennae are almost as long as the body
  • faint, white zigzag line across the center of the back
Squash bug
Squash bug.

Squash Bug

  • Common on foliage and fruit of pumpkins and squash in late summer
  • 1-inch long
  • gray-black or brown in color,
  • longate oval and pointed at the head end
  • hide in winter under old vines, under leaves, clods, stones and other debris.
  • rarely found indoors

BMSB is reported from approximately 47 different states, including Iowa. A single dead specimen was collected in Cedar Rapids, Iowa in February, 2011 and submitted to ISU for diagnosis. Since then, BMSB has been reported from over one-third of Iowa. BMSB travels readily in shipping containers and with people. Adults and nymphs feed on sap from a wide variety of plants and in the fall of the year accidentally wander inside buildings as a nuisance pest. For more information please see the HHPN article, "Brown Marmorated Stink Bug".

Links to this article are strongly encouraged, and this article may be republished without further permission if published as written and if credit is given to the author, Yard and Garden, and Iowa State University Extension and Outreach. If this article is to be used in any other manner, permission from the author is required. This article was originally published on September 1, 2016. The information contained within may not be the most current and accurate depending on when it is accessed.