GALL
The larve begins its existence between the youngest leaves, but soon bores itself down through the growing point and hence feeds upon the inside of the very tip of the stem. The topmost 2-4 internodes are completely shortened, their leaf sheaths are contracted. The solitary, yellowish, larva lies in a chamber just below the growing point; the wall of the larval chamber is not thickened, green, and is not sclerified after the summer. Pupation internal, after hibernation. The maximal thickness of the gall is less than twice the thickness of the stem just below.

HOSTPLANTS
Paaceae, monophagous: Phragmites australis.

Lipara similis and L. rufitarsis were found throughout Rhode Island infesting both native and exotic P. australis, but their presence and abundance varied among sites. Within stands ... L. rufitarsis infests the shorter, thinner exterior stems [and] reduces stem length by 37% ... Both Lipara species prevent infested stems from flowering. In adjacent stands of native and exotic P. australis, L. rufitarsis infests significantly more native stems than exotic stems ...