Lygaeus kalmii, known as the small milkweed bug or common milkweed bug, is a species of seed bug in the family Lygaeidae. It is found in Central and North America.[1][2][3]
Lygaeus kalmii was first formally named in 1874 by Swedish entomologist Carl Stål in his Enumeratio Hemipterorum.[4][3]
There are two recognized subspecies:[3]
Young nymphs of Lygaeus kalmii are initially fully red, developing black diagonal markings on the pronotum. Adults are orange to red and gray/black, reaching 10 to 12 mm (0.39 to 0.47 in) in length. The head is black with a red spot in the center. The forewings are patterned with a black heart inside of an orange-red X which does not meet in the middle.[2][5]
The membranous portion of the forewings in the eastern subspecies Lygaeus kalmii angustomarginatus has a narrow white margin, while that of the western L. k. kalmii has white spots and a broader margin.[2]
The small milkweed bug is commonly confused with other black and red or orange insects, including Oncopeltus fasciatus, Lygaeus turcicus, and Lygaeus reclivatus.[6]
Lygaeus kalmii angustomarginatus is found in north temperate regions of North America and is not a migratory insect.[7] Only adults overwinter and they do not begin reproduction until the following April. Females are receptive to males in all seasons.[8] The eggs are laid on milkweed (Asclepias spp.) in the spring.[2]
Small milkweed bugs' primary sources of nutrients are flower nectar and milkweed seeds. If these food sources are limited, they may feed on other insects.[9]
Adult Lygaeus kalmii Lygaeus kalmii, known as the small milkweed bug or common milkweed bug, is a species of seed bug in the family Lygaeidae. It is found in Central and North America.
