Common Name: Yellowmargined leaf beetle
Scientific Name: Microtheca ochrolema Stål
Description: Adult beetles are 3/8 inch long and dark brown to black. The wing covers (elytra) are textured with rows of pits and light cream-colored margins along the outer edges. Larvae are 3/8 inch long grub-like, dark brown to black and have three pairs of short legs behind the head. This species was accidentally introduced from South America and was first detected in New Orleans in 1945 on grapes from Argentina. Since then, it has spread to other southeastern states and into eastern Texas during the 1970’s.
This beetle has been confused with flea beetles. However, the hind legs of the yellowmargined leaf beetle are not enlarged for jumping as they are in flea beetles.
Life Cycle: Adult beetles overwinter and mate soon after emerging from the pupa. Larvae hatch from eggs and develop through several stages before pupating. Development from egg to adult occurs over about 23 days. Adults leave the host plant and enter a resting stage (estivation) about mid-June and remain there until October.
Habitat and Food Source(s): Mouthparts are for chewing. Leaves of mustard greens, turnip greens, collard greens, Chinese cabbage, bok choy, radish, Irish potato, watercress and roses are consumed by adults and larvae, giving them a tattered appearance with many irregularly shaped holes. Populations increase and damage is more severe in spring and fall.
Pest Status: Adult and larval stages feed on foliage of certain vegetables including mustard and turnip greens; medically harmless.
Literature: Drees 1990.