Nose Bot Fly of Horses vs Eastern Calligrapher

Side-by-side species comparison

Attribute Nose Bot Fly of Horses Eastern Calligrapher
Scientific Name Gasterophilus haemorrhoidalis Toxomerus geminatus
Order Diptera Diptera
Family Oestridae Syrphidae
Size 10-14 mm 5-7 mm
Habitat Farmland Woodlands
Diet Omnivores Nectar Feeders
Regions Europe, North America, Asia, North Africa North America
Conservation Least Concern Least Concern

Nose Bot Fly of Horses

A dark-bodied bot fly that deposits reddish-black eggs around the lips of horses. Larvae penetrate the lip mucosa and migrate to the stomach, then before pupation they reattach to the rectal mucosa, causing irritation and inflammation. The name refers to the reddish rectal inflammation it causes.

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Did You Know?

Before pupation, larvae reattach to the horse's rectum, causing such irritation that affected horses may rub their tails raw.

Eastern Calligrapher

A tiny hoverfly with intricate black calligraphic markings on a yellow abdomen. It is one of the most abundant flower flies in eastern North America.

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Did You Know?

Despite its small size, it is one of the most effective aphid predators in North American gardens.