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turnip moth

n. A moth of the family Noctuidae, ''Agrotis segetum'', whose larvae called cutworm cause damage to a wide variety of crop.

Wikipedia
Turnip moth

The turnip moth (Agrotis segetum) is a moth of the family Noctuidae. It is a common European species, but it is also found in Asia and Africa, very likely having been spread by the international trade in nursery stock. It is a cutworm in the genus Agrotis, which possibly is the genus that includes the largest number of species of cutworms.