milkweed bug

insect

Also known as: Oncopeltus fasciatus

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Last updated

June 30, 2026

Quick Summary

The milkweed bug (Oncopeltus fasciatus) is a large insect, typically black with reddish-orange bands. It belongs to the lygaeid bug family, which includes many species that can be crop pests. Milkweed bugs primarily feed on milkweed plants. These plants are known for their milky sap, which can make the insects that feed on them distasteful to predators. Milkweed plants are also crucial for the larvae of various butterflies, including monarch butterflies.123

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lygaeid bug
The large milkweed bug (Oncopeltus fasciatus) is distinguished by its broad red and black bands. They range from 3 to 15 mm (0.1 to 0.6 inch) in length, although they are usually less than 10 mm.
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The large milkweed bug (Oncopeltus fasciatus) is distinguished by its broad red and black bands. They range from 3 to 15 mm (0.1 to 0.6 inch) in length, although they are usually less than 10 mm.
Read More