Caryomyia shmoo Gagne, new species

Hosts: Carya tomentosa, texana, pallida, glabra, ovata

Gall (Figs. 59-61): Common, found on Eucarya hickories; single or clustered, on lower leaf surface between veins; 2.5-3.5 mm in height, bilaterally symmetrical, truncate-spheroidal at base, apical third abruptly narrowed, set to one side, and tipped with an umbo; green to yellow, turning tan to brown, smooth, hairless, not sticky; base with prominent conical pedicel set into circular indentation, leaf without conspicuous exfoliation surrounding base of gall; wall firm, brittle, thin, larval chamber shaped as for gall, glabrous, with longitudinal ridges. This gall resembles most that of the related species, C. caryae. The gall of the latter is spheroidal but that of C. shmoo is conspicuously narrowed at its apical third.

Affinities. — This species forms a natural group with C. caryae and C. hirtiglobus because of the general shape of the gall.

Biological notes. — Soft, whitish-green galls were first noted in central Maryland on June 9 and contained first instars. On June 15, full grown galls were brittle and still contained first instars. By July 8, galls contained second and third instars. When full-grown, the white larva fills the entire larval chamber and is very active when disturbed. Pupae exit the gall from one side through which the larva has already scraped away part of the wall.

Range: AL, AR, CT, FL, GA, LA, MD, MS, MO, NH, NY, NC, OH, PA, SC, TX, VA, DC, WV