What pest is known for its metallic blue or green appearance?

The pest known for its metallic blue or green appearance is the blow fly. Blow flies belong to the family Calliphoridae, and many species exhibit strikingly vibrant colors, often iridescent shades of blue or green. This characteristic coloration is often one of the most distinguishing features of blow flies, making them easily identifiable compared to other common flies.

Blow flies are particularly known for their role in forensic entomology due to their attraction to decaying organic matter, where they lay their eggs. Understanding the traits of these pests, including their appearance, can help in pest identification and control strategies.

The other options listed—house flies, bottle flies, and fruit flies—do not typically possess this metallic sheen. House flies are more grayish and lack the vibrant coloration, while bottle flies are a different category of flies that also do not show the metallic quality associated with blow flies. Fruit flies, on the other hand, are much smaller and usually brown with distinctive red eyes, having no similarity to the unique coloration of blow flies. Recognizing these differences is crucial for effective pest management and accurate identification in structural settings.