Piceacecis (Diptera: Cecidomylidae), A New Genus For A Non-Native Pest Of Norway Spruce From Europe And Its North American Relative

Dasineura abietiperda (Henschel), a European pest of Norway spruce, Picea abies (Pinaceae), is reported as new to northeastern North America where the tree is widely planted and valued as an ornamental. Adult gall midges emerge in early spring, mate and deposit eggs on twigs or new shoots. The larvae burrow into tissue causing swellings to form under bud scales and less frequently along shoots or near the terminal bud. Larvae overwinter in the galls. Field symptoms include bent twigs or shoots, swellings in nodes and needle drop. A new genus, Piceacecis Gagne is described to include D. abietiperda and its North American relative, Phytophaga tsugae (Felt), which occurs on native American white spruce, Picea glauca. Both cecidomyiids are redescribed with illustrations. The names of both are new combinations in Piceacecis, and Phytophaga piceae Felt is a new junior synonym of Piceacecis tsugae. In the past these synonyms have been combined also with Mayetiola.