Synonyms and other taxonomic changes
Lygaeus kalmii Stal
Identification
Adult: dark gray to black with broad orange or red band on forewing, forming an "X" shape that doesn't quite meet in the middle; head black with dull red spot on top, sometimes extending down onto face; pronotum with red transverse band, bordered anteriorly by two black spots, and posteriorly by two black semicircular lobes; membranous portion of forewing all black in eastern specimens
In western specimens, the membranous portion of the forewing is black with large white spots and white posterior margin
Nymph: abdomen all red in young nymphs, developing black spots with age; wingpads black, lengthening with age; pronotum red with two black diagonal markings
Range
Much of United States and southern Canada
Habitat
Fields, meadows containing milkweed and other flowers
Season
February-October
(1); though it should be noted that BugGuide also has some records for the months of November-January for certain states
Food
Adults suck nectar from flowers of various herbaceous plants, and also feed on milkweed seeds(?). Also reported to be scavengers and predators, especially in spring when milkweed seeds are scarce.
Life Cycle
Eggs are laid on milkweed in spring. One or more generations per year. Adults overwinter.
See Also
Adults of the
Large Milkweed Bug (
Oncopeltus fasciatus) have a different pattern on the leathery portion of the forewing: an orange forward-pointing triangle anteriorly, and an orange backward-pointing triangle posteriorly, separated by a black band in the middle.
Nymphs of the Large Milkweed Bug are more orange than red, and lack two diagonal black markings on the pronotum.
Adults of the
Eastern Boxelder Bug (
Boisea trivittata) lack a red "X" pattern on forewing, and have three longitudinal red stripes on the pronotum, not a red transverse band.
Adults of the
Western Boxelder Bug (
Boisea rubrolineatus) are mostly black with very little red.
Print References
Arnett, p. 258, fig. 20.28--mislabeled
Oncopeltus (1)
Slater, p. 71, fig. 120
(3)
Milne, p. 478, fig. 116
(5)
Arnett and Jacques, #57
(6)
Borror and White, plate 3
(7)
Internet References
live adult images (Bruce Marlin, Illinois)
preserved adult image and foodplant (Virtual Exhibit on Canada's Biodiversity)
