Sweat Fly vs Deer Bot Fly

Side-by-side species comparison

Attribute Sweat Fly Deer Bot Fly
Scientific Name Hydrotaea irritans Cephenemyia stimulator
Order Diptera Diptera
Family Muscidae Oestridae
Size 5-7 mm 12-15 mm
Habitat Farmland Woodlands
Diet Dung Feeders Parasites
Regions Europe, North America Europe
Conservation Least Concern Least Concern

Sweat Fly

A small dark fly attracted to perspiration on humans and livestock. It forms dense head-circling swarms in summer that can be extremely annoying.

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Did You Know?

Swarms of these flies can reduce cattle weight gain by causing constant head-tossing behavior.

Deer Bot Fly

A parasitic fly that deposits larvae in the nostrils of roe deer. The larvae develop in the pharyngeal region before being sneezed out.

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Did You Know?

Once erroneously claimed to fly at over 1,300 km/h, making it a famous example of scientific exaggeration.