Neuroterus floccosus (Bassett, 1881), comb rev., sexual generation

[Synonyms listed for agamic gall]

Material examined: Nine asexual females labelled as “Canada, Manitoba, Assiniboine Forest, 49.85862°N, - 97.25015°W, GPS ±10m, S. Digweed, Collected 2005.viii.30 ex Quercus macrocarpa, Reared 15-25.v.2006 ex gall of Neuroterus quercusverrucarum agamic gen.”, determined originally as Neuroterus quercusverrucarum asexual generation females by S. Digweed. Seven sexual females and 4 males labelled as “Canada, Alberta, Edmonton, Northern Forest Centre, 53.49165°N, -113.54291°W, GPS ±10m, Reared 4-13.vii.2006 ex galls of Neuroterus quercusverrucarum ♂♀ ex Quercus macrocarpa, S. Digweed”

Gall. Sexual generation minute (approximately 1mm long), ovoid, seed-like integral leaf galls, smooth and only covered with normal leaf pubescence (Fig. 150). Galls are visible and project slightly from both upper and lower leaf surfaces, and often but not always occur alongside major leaf veins. Galls appear reddish-brown from above and paler tan from below. Exit holes of adult insects generally occur on the underside of the leaf.

Biology. Asexual galls (Fig. 149) have been recorded on leaves of Q. bicolor and Q. macrocarpa. Galls become apparent in August as small depressions filled with loose, pale wool on the underside of new, terminal, long shoot leaves. Multiple galls often co-occur on a single leaf, which causes the leaf to curl, and galls tend to be found on stumps or damaged trees bearing vigorous, long late-season shoots. Adult females of the asexual generation emerge the spring following gall induction, from mid-April to late May. Galls of the sexual generation first appeared in late May on Q. macrocarpa in Edmonton, and adults emerged in late July and early August.

Distribution. USA: from Virginia west to Illinois (Burks 1979). Canada: Ontario (Burks 1979), Manitoba. This species was only reared in sleeves in Edmonton, Alberta, and does not naturally occur on bur oak there.