Tuesday, July 21, 2009

Milkweed Bugs

Milkweed bugs are in the classification Hemiptera (True Bugs). The first two pictures are the Large Milkweed Bug (Oncopeltus fasciatus). The first picture is of several stages of nymphs, the second is how they appear as adults. The third picture is the Small Milkweed Bug (Lygaeus kalmia).
Large Milkweed bugs measure up to 3/4 of an inch. They are orange and black like the Small Milkweed Bug which measures about 10/16 of inch. One distinguishing characteristic of the Large variety is the black band through the middle of their back. The Small variety lacks this band instead they have a somewhat cross shaped orange marking on their wings. Each species uses milkweed as the host plant for their young. Females lay eggs on milkweed and the nymphs feed on the plant. This makes them toxic for consumption to possible predators. Both species can be found throughout most of the US. The Small variety has a larger range then the Large variety. Look for them in many types of habitats, but always in association with Milkweed.


  1. I really enjoyed this colourful post. You might like my red bugs here. Any help with the last one (in particular - though not a good photo) would be appreciated! Greetings from Wales, UK - though my 'bug pix' were taken in Greece.

  2. Thanks Caroline, I headed over to your blog and left a comment there. My husbands family is from Wales originally. We've always talked of visiting there someday.