Walshomyia cupressi

This gall midge induces large, monothalamous, four-sided galls in summer on at least two cypress species.

They appear as massive replicas of the terminal buds and often occur in clusters of three or four individual galls.

Galls at different stages of development can be found from spring through fall.

Vigorously growing cypress trees seem to host more galls than stunted specimens nearby.

Hosts:
Hesperocyparis pygmaea (Mendocino cypress)
Hesperocyparis sargentii (Sargent cypress)

This species causes a gall on buds of Cupressus pygmaea (Lemmon) Sarg. and C. sargentii Jeps. The gall is a greatly swollen bud.

CYPRESS GALL MIDGE
Walshomyia cupressi Pl. 40

This midge induces large, monothalamous, four-sided galls insummer on at least two cypress species in California. They appear as massive replicas of the terminal buds and often occur in clusters of three or four individual galls.

Walshomyia cupressi

Greatly enlarged bud
Adults emerge from the buds in April

Hosts: Cupressus pygmaea, C. sargentii

Distr: CA