Striped flea beetle (Phyllotreta striolata)
The striped flea beetle (Phyllotreta striolata) is a small flea beetle, shiny black with a greenish tinge, 1.5 to 2.5 mm long, having a wavy amber line running the length of each elytron (wing cover). It is a pest of cabbage and other brassicas. The hind legs are thickened, enabling the beetle to jump like a flea when disturbed. Although the larvae live in the soil, feeding on the roots of host plants, they are not significant pests. Rather, the primary damage is caused by adult beetles feeding on the foliage. With their chewing mouthparts, beetles make small round pits in the cotyledons and leaves of young plants. As the plants grow, the remaining thin layers of tissue eventually dry up and fall away, leaving small "shot holes" in the foliage. This type of injury is capable of killing young plants. The seedlings may be killed if severe damage occurs. In addition, beetles may act as vectors of plant disease.