Oncopeltus fasciatus

Large Milkweed Bug

Oncopeltus fasciatus, Large Milkweed Bug



Family: Lygaeidae

Subfamily: Lygaeinae

Length: 10 - 18 mm


Oncopeltus fasicatus lives out its life on milkweed plants. Mating, egg-laying, development of larvae, and courtship all take place on these plants. The primary food is milkweed seed, while the insects also feed on milkweed plant juices. The milkweed diet makes the bugs unpalatable, and they sport aposematic coloring. The species ranges from Ontario to South America, including the West Indies.

Researchers have documented flights of one hour or more in this species, and have described it as "migratory." It does seem clear the species flies into areas where the winter climate is too cold for it to overwinter, waiting until the warmth of Spring to make such flights (see for example Dingle, 1964, 1981).

Raising this species in the lab has become so routinized that Oncopeltus fasciatus has become the standard lab animal for general entomological research.

Koerper and Jorgensen (1984), for example, reported a technique for rearing that went through a new cycle every thirteen weeks, with 400 nymphs and 195 adults constantly present. The food requirements for such a colony was 25 grams of sunflower seeds per cycle.

Photo locations: top two photos are from Upshur County, West Virginia; bottom photo is from Sacatepéquez department, Guatemala.

Mating Large Milkweed Bugs, Oncopeltus fasciatus


Oncopeltus fasciatus, Large Milkweed Bug, Guatemala image

Map, Oncopeltus fasciatus

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