Phanacis hypochoeridis (Kieffer, 1887)

Nomenclature: Aulax hypochaeridis Kieffer, 1887

Feeds on: Induces galls on Hypochaeris radicata L.

Distribution: United States: California, Oregon; Canada: British Columbia

Aylax hypochaeridis

Hypochaeris radiata
Fusiform swelling of midrib and peduncle. Widely distributed in western Oregon and Washington where it helps to check the spread of its introduced host plant. Galls have ben seen at OR-CA state line and in San Diego CA.

Phanacis hypochoeridis
Catsear stem gall wasp

Host: Catsear (Hypochaeris radicata).

Gall location: On the stem, typically midway down the length of the stem.

Description: Elongate, spindle-shaped swellings containing many chambers, often 1-5 centimeters in length. Green and fleshy when fresh to brown and dry when old.

Range: This species is primarily known in North America from the West Coast, particularly California, Oregon, and British Columbia. A small population has apparently been identified in North Carolina.

This species was introduced to North America from Europe along with its host plant. Catsear occurs throughout most of the United States and some parts of Canada, so the gall may occur in additional states not listed above. The catsear gall wasp and the dandelion gall wasp (Phanacis taraxaci), both of which are introduced species, are the only representatives of the gall wasp tribe Phanacidini to be found in North America.