Caloptilia alnivorella

Description

The alder leafminer (Caloptilia alnivorella) is a moth of the family Gracillariidae. It is known from the Russian Far East, Canada (Québec, Nova Scotia, Ontario and the Northwest Territories) and the United States (including Vermont, Utah, Maine, California, Colorado and Michigan). The wingspan is about 14 mm. Adults overwinter in the fall and come out in the spring to mate. The larvae feed on Acer negundo, Alnus species (including Alnus crispa var. mollis, Alnus glutinosa, Alnus incana, Alnus japonica, Alnus mollis, Alnus rubra, Alnus tenuifolia and Alnus viridis), Betula papyrifera and Quercus garryana. They mine the leaves of their host plant. The mine starts as a short, narrow, Phyllocnistis-like mine on the upper side of the leaf. Later instars form tents by bending the lateral edges and attaching them together. Within the tent, a small fold is made at the edge for a pupation site. The cocoon is found within the fold or on the surface of the leaf.