[Resseliella] clavula. Canada (Ontario), USA (Indiana to Massachusetts, S to Virginia). Cornus florida (Cornaceae).
Cecidomyia clavula Beutenmüller 1892: 269. USA: New York, New York, Staten I.; HT; L; AMNH. Ref. Gagné et al. 2019 (compared with R. maxima)
Mycodiplosis alternata Felt 1907a: 30. USA: New York, Albany; HT; ♂; NYSM.

Lasioptera clavula

Cecidomyia clavula

Gall.--On the terminal twigs of dogwood (Cornus florida). It is club-shaped and about 0.5 to 1 inch long. Inside is an elongate channel inhabited by one or more larvae.

The larvae leave the gall in September and October and enter the ground to transform. They overwinter and the adults emerge during May and June.

Smooth, clublike enlargement just below bud in apical branches...Resseliella clavula (Beutenmüller)

Eggs are deposited among terminal leaves in spring...The twigs usually do not elongate beyond the galls and there is often a pair of wilted leaves beyond. The swellings are 2–3 cm long, green to red, and especially conspicuous in the fall after the orange larvae have dropped to the ground for the winter...Host: C. florida...