Mamestra configurata

Definition

A noctuid moth species commonly known as the Bertha armyworm, native to western North America and Mexico. The larvae are significant agricultural pests, particularly of canola, mustard, and other Brassicaceae crops, capable of causing extensive defoliation during outbreak years. Adults are medium-sized, cryptically colored moths with forewings that show considerable individual variation in pattern—hence the specific epithet *configurata*.

Etymology

From Latin *configuratus* (arranged, shaped), referring to the variable wing patterns; genus *Mamestra* from an arbitrary Latinized name.

Example

In the Canadian prairies, Mamestra configurata populations are monitored annually using pheromone traps to predict larval densities in canola fields and time insecticide applications before economic thresholds are exceeded.

Synonyms

• Bertha armyworm

Related Terms

• Noctuidae
• Lepidoptera
• Armyworm
• agricultural pest
• pheromone trap
• Economic threshold

Usage Notes

The common name "Bertha armyworm" is used throughout Canadian and U.S. agricultural extension literature; the species epithet is sometimes misspelled *configuratus* due to confusion about grammatical gender agreement. Population outbreaks are cyclic and can be locally devastating, though the species is also a host for nucleopolyhedroviruses (McNPV) used in biocontrol research.