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Species Lygaeus kalmii - Small Milkweed Bug

Small Milkweed Bugs Mating - Lygaeus kalmii - male - female Small Milkweed Bug - Lygaeus kalmii ID Needed - Lygaeus kalmii Small Milkweed Bug - Lygaeus kalmii Small Milkweed Bug - Lygaeus kalmii Small Milkweed Bug - Lygaeus kalmii Small Milkweed Bug - Lygaeus kalmii Lygaeus kalmii
Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Hemiptera (True Bugs, Cicadas, Hoppers, Aphids and Allies)
Suborder Heteroptera (True Bugs)
Infraorder Pentatomomorpha
Superfamily Lygaeoidea
Family Lygaeidae (Seed Bugs)
Subfamily Lygaeinae
Genus Lygaeus
Species kalmii (Small Milkweed Bug)
Other Common Names
Common Milkweed Bug
Synonyms and other taxonomic changes
Author: Stal 1874
Size
body length 10-12 mm
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
Typical nymph: , occasionally:
Range
widely dist., but rare in se US, and n. Great Plains and Rocky Mtn states (BG data)
Habitat
Fields, meadows containing milkweed and other flowers
Season
Mostly: Jun-Oct, yr round in CA (BG data)
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. They have been reported feeding on honey bees, monarch caterpillars and pupae, and dogbane beetles, among others. The Life of a Californian Population of the Facultative Milkweed Bug Lygaeus kalmii
"Adults mainly feed on milkweed seeds, but they often consume nectar from various flowers." Harvard Entomology
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
Brimley, p. 67 (1)
Arnett, p. 258, fig. 20.28--mislabeled Oncopeltus (2)
Slater, p. 71, fig. 120 (3)
Rea, p. 36 (4)
Milne, p. 478, fig. 116 (5)
Arnett and Jacques, #57 (6)
Borror and White, plate 3 (7)
Salsbury, p. 101 (8)
Internet References
live adult images (Bruce Marlin, Illinois)
preserved adult image and foodplant (Virtual Exhibit on Canada's Biodiversity)
Works Cited
1.Insects of North Carolina
C.S. Brimley. 1938. North Carolina Department of Agriculture.
2.American Insects: A Handbook of the Insects of America North of Mexico
Ross H. Arnett. 2000. CRC Press.
3.How to Know the True Bugs
Slater, James A., and Baranowski, Richard M. 1978. Wm. C. Brown Company.
4.Milkweed, Monarchs and More: A Field Guide to the Invertebrate Community in the Milkweed Patch
Ba Rea, Karen Oberhauser, Michael Quinn. 2003. Bas Relief Publishing Group.
5.National Audubon Society Field Guide to Insects and Spiders
Lorus and Margery Milne. 1980. Knopf.
6.Simon & Schuster's Guide to Insects
Dr. Ross H. Arnett, Dr. Richard L. Jacques. 1981. Fireside.
7.A Field Guide to Insects
Richard E. White, Donald J. Borror, Roger Tory Peterson. 1998. Houghton Mifflin Co.
8.Insects in Kansas
Glenn A. Salsbury and Stephan C. White. 2000. Kansas Dept. of Agriculture.