Other Common Names
Southern Corn Rootworm (in the larval stage)
Synonyms and other taxonomic changes
Chrysomela duodecimpunctata Fabricius (for subspecies D. u. howardi)
Crioceris sexpunctata Fabricius (for subspecies D. u. howardi)
Diabrotica duodecimpunctata Fabricius (for subspecies D. u. howardi)
Diabrotica soror LeConte
Size
Adults variously reported as between 5 - 9mm long.
Larvae to 8mm.
Identification
Adults yellow to greeen with eleven black spots on the elytra.
Subspecies identification from
EPPO Data Sheets: In
D. u. undecimpunctata, the abdomen is greenish-yellow with 11 black spots on the elytra (Arnett, 1985), while in
D. u. howardi, it is yellow to yellowish-red with 12 large black spots. The head, antennae and legs are entirely black (
howardi) or with some greenish-yellow (
undecimpunctata).
Food
Larvae feed on roots of a wide range of plants, including many field crops.
Life Cycle
Overwinters as an adult in southern states. Eggs are laid at soil surface or below at the base of food plants. Larvae hatch in 7 - 10 days and feed for three to six weeks. The larvae pupate at the base of host plants and emerge as adults in 1-2 weeks.
Remarks
Considered a major pest of many field crops including cucumbers and other squashes, corn, soy. Beetles also transmit crop diseases such as bacterial wilt. Adults also reported damaging to garden plants including hibiscus, roses.
Southern and eastern subspecies is D. undecimpunctata howardi. There is also a subspecies named D. undecimpunctata undecimpunctata, Western Spotted Cucumber Beetle, found only in Arizona, California, Colorado and Oregon.
Internet References
Texas Beetles includes range map
