Window Gnat vs Greater Bee Fly

Side-by-side species comparison

Attribute Window Gnat Greater Bee Fly
Scientific Name Sylvicola fenestralis Bombylius canescens
Order Diptera Diptera
Family Anisopodidae Bombyliidae
Size 5-7 mm 10-14 mm
Habitat Underground Deserts & Drylands
Diet Sap Feeders Nectar Feeders
Regions Europe Southern Europe, North Africa, Western Asia
Conservation Least Concern Least Concern

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.

Greater Bee Fly

A pale greyish bee fly with a long proboscis and clear wings. It parasitizes ground-nesting bees in arid Mediterranean habitats.

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Did You Know?

It can hover motionless in the air for extended periods while probing flowers with its rigid proboscis.