Arctic Grayling vs Nose Bot Fly of Horses

Side-by-side species comparison

Attribute Arctic Grayling Nose Bot Fly of Horses
Scientific Name Oeneis bore Gasterophilus haemorrhoidalis
Order Lepidoptera Diptera
Family Nymphalidae Oestridae
Size 38-48 mm wingspan 10-14 mm
Habitat Mountains Farmland
Diet Omnivores Omnivores
Regions Arctic Scandinavia, Finland, northern Russia, Siberia, Alaska, northern Canada Europe, North America, Asia, North Africa
Conservation Least Concern Least Concern

Arctic Grayling

A pale grayish-brown butterfly with a translucent, papery wing quality and subtle darker striations. Its cryptic appearance makes it nearly invisible on lichen-covered rocks. Adults are extremely wary and difficult to approach.

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Did You Know?

When this butterfly lands on lichen-covered rocks, it tilts sideways to align its wing veins with the rock cracks, achieving near-perfect camouflage.

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.