Eyed Elater Glowworm vs Throat Bot Fly of Horses

Side-by-side species comparison

Attribute Eyed Elater Glowworm Throat Bot Fly of Horses
Scientific Name Phengodes fusciceps Gasterophilus nasalis
Order Coleoptera Diptera
Family Phengodidae Oestridae
Size 15-25 mm (females) 11-15 mm
Habitat Woodlands Farmland
Diet Omnivores Omnivores
Regions Eastern United States Worldwide wherever horses are kept
Conservation Least Concern Least Concern

Eyed Elater Glowworm

A railroad worm beetle whose larviform females emit light from paired organs along the body. Males are short-lived, winged, and do not glow.

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Did You Know?

Females produce both green light from their body segments and red light from their head, resembling a tiny railroad train at night.

Throat Bot Fly of Horses

A yellowish-brown bot fly that lays eggs under the jaw of horses. Larvae migrate to the area between the teeth and gums before traveling to the pyloric region of the stomach and duodenum. It is one of the most common horse bot flies worldwide.

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Did You Know?

Unlike other horse bots, this species' larvae prefer the duodenum over the stomach, a unique niche among Gasterophilus species.