Host plants:
The caterpillar lives in basal parts and in the rhizome of reed (Phragmites).
Habitat:
Rhizedra lutosa inhabits reeds on more or less damp to wet standing plants, but that are not covered by water.
Life cycle:
The eggs overwinter. The caterpillar lives from mid-April to early August. The infested stems die off completely. If one draw at these, they usually just break off below the ground level and you realize the hollowed feeding tunnel that is filled by droppings. The larva is then usually already lower down in the rhizome. Once I was lucky enough to draw a larva up, too.
The moths fly in the autumn from late August to November and rest on old reed during daytime. I found a still quite well-preserved male on the Upper Rhine on 01/11/2011 resting on old reeds.
Endangerment factors:
Reed beds have been and still are further decimated in many places (especially by agriculture, also by overbuilding, reforestation).
Remarks:
Rhizedra lutosa occurs in Europe and temperate Asia to Japan.