Blandford Fly vs Window Gnat

Side-by-side species comparison

Attribute Blandford Fly Window Gnat
Scientific Name Simulium posticatum Sylvicola fenestralis
Order Diptera Diptera
Family Simuliidae Anisopodidae
Size 2-3 mm 5-7 mm
Habitat Rivers & Streams Underground
Diet Blood Feeders Sap Feeders
Regions Europe Europe
Conservation Least Concern Least Concern

Blandford Fly

A notorious black fly that causes severe allergic reactions with its bite around the Blandford area of Dorset. Females need blood meals for egg development. Larvae develop in clean rivers.

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Did You Know?

Named after Blandford Forum in Dorset where outbreaks of painful bites affect thousands of people each summer.

Window Gnat

A small, delicate fly with dark-spotted wings often found resting on windows and walls. Larvae develop in fermenting organic matter and tree sap runs.

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Did You Know?

Despite being one of the most commonly encountered flies on windows throughout Europe, this species remains largely unstudied and overlooked by entomologists.