Many are serious pests of cultivated plants , for example the Colorado potato beetle ( Leptinotarsa decemlineata ) , the asparagus beetle ( Crioceris asparagi ) , the cereal leaf beetle ( Oulema melanopus ) , and various flea beetles , and a few act as vectors of plant diseases .
Many are serious pests of cultivated plants , for example the Colorado potato beetle ( Leptinotarsa decemlineata ) , the asparagus beetle ( Crioceris asparagi ) , the cereal leaf beetle ( Oulema melanopus ) , and various flea beetles .