Actinoptera discoidea (Fallén, 1814)
on Gnaphalium, Helichrysum
in spring the larvae induces an onion-shaped, almost a cm high rosette gall. In summer either a fusiform, up to 6 mm long swelling of a stem or the larve lives in the sclerified receptacle; larva a white maggot, always solitary.
Asteraceae, narrowly oligophagous