Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Clickable Guide
Moths Butterflies Flies Caterpillars Flies Dragonflies Flies Mantids Cockroaches Bees and Wasps Walkingsticks Earwigs Ants Termites Hoppers and Kin Hoppers and Kin Beetles True Bugs Fleas Grasshoppers and Kin Ticks Spiders Scorpions Centipedes Millipedes

Upcoming Events

Photos of insects and people from the 2015 gathering in Wisconsin, July 10-12

Photos of insects and people from the 2014 gathering in Virginia, June 4-7.

Photos of insects and people from the 2013 gathering in Arizona, July 25-28

Photos of insects and people from the 2012 gathering in Alabama

Photos of insects and people from the 2011 gathering in Iowa

Photos from the 2010 Workshop in Grinnell, Iowa

Photos from the 2009 gathering in Washington


Species Lygaeus kalmii - Small Milkweed Bug

Small Milkweed Bug - Lygaeus kalmii Small Milkweed Bug - Lygaeus kalmii Small milkweed bugs - Lygaeus kalmii Small Milkweed Bug - Lygaeus kalmii Lygaeus kalmii Small Milkweed  Bug  Nymph - Lygaeus kalmii Lygaeus kalmii? - Lygaeus kalmii New to me. - Lygaeus kalmii
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
body length 10-12 mm
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:
widely dist., but rare in se US, and n. Great Plains and Rocky Mtn states (BG data)
Fields, meadows containing milkweed and other flowers
Mostly: Jun-Oct, yr round in CA (BG data)
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

Another example of scavenging
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.