Japanese Horntail vs Yellow Ophion

Side-by-side species comparison

Attribute Japanese Horntail Yellow Ophion
Scientific Name Eriotremex formosanus Ophion obscuratus
Order Hymenoptera Hymenoptera
Family Siricidae Ichneumonidae
Size 20-35 mm 14-18 mm
Habitat Woodlands Farmland
Diet Wood Feeders Parasitoids
Regions East Asia, Taiwan, introduced to southeastern United States Europe
Conservation Least Concern Least Concern

Japanese Horntail

A large wood wasp with a robust reddish-brown body and dark wings. Native to East Asia, it attacks stressed and recently felled hardwood trees.

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Did You Know?

This species was first detected in North America in 1974 and is one of the few tropical siricid wood wasps to establish invasive populations.

Yellow Ophion

A laterally flattened, tawny-yellow parasitoid wasp active at dusk and after dark. Its larvae develop as internal parasitoids of noctuid moth caterpillars.

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Did You Know?

Its laterally compressed abdomen is thought to help it slip between grass blades when searching for host caterpillars.