Phylloxerina nyssae (Pergande)

Galls are usually crescent-shaped, yellowish-white, formed in spring by rolling, scalloping and swelling of edges of leaves of Nyssa sylvatica (Stoetzel 1993). Later in the year (September), lemon-yellow apterae, BL 1.0-1.3 mm, completely covered in white wax wool, occur together with sexuales in bark crevices of young trees, particularly in cavities caused by dropping out of dead twigs about 2 m above ground level. Apparently there is no host alternation. In Maryland and Washington D.C., USA (Pergande 1904).

Cecidomyia nyssaecola

Nyssa

Marginal leaf fold, length 2.5 to 3.5 mm

Cecidomyia nyssaecola sp. nov.

Gall. This is made by a narrow upward and inward fold of the margin of the leaf of sour gum (Nyssa sylvatica) and measures about .3 to 1 mm in diameter and from about 2.5 to 3.5 mm in length. Sometimes only a few of the folds occur on a leaf and again the entire margin on both sides of the leaf is covered with them, causing the leaf to become scalloped. The gall is pale yellowish or yellowish green and contrasts with the dark green leaf, making it a rather conspicuous object, readily detected. The galls are sometimes more or less contiguous when occurring in numbers on the same leaf. When dry the gall becomes brown.

Habitat: VA, KY, IL, NY, NJ, PA, NC

Very common everywhere in the vicinity of New York, from which locality my specimens were obtained. The gall may be found in June and the fly emerges in July.

Cartodiplosis nyssaecola

Host: Nyssa sylvatica

Marginal leaf folds
This species was originally believed to cause this gall, which is actually formed by Phylloxera nyssae. C nyssaecola is a predator on the phylloxeroids.

Range: NY and MD