Celticecis semenrumicis (Patton)

Cecidomyiaceltis semenrumicis
Cecidomyia semenrumicis

Hosts: Celtis laevigata, occidentalis

Gall.--On twigs, occasionally on petioles or stronger veins on either side of the leaf; upright, with 3–6 prominent, longitudinal, narrow, lateral wings and long, slender, curled apex; surface hairless, matte, green turning tan, or wholly or partly red; 6–8 mm long, 4–6 mm wide at mid-length; connection to twig or leaf a broad, persistent callus; when on leaf apparent on reverse as a widened vein; gall in cross section an elongate-ovoid larval chamber surrounded by thin wall beyond which the wings radiate.

Affinities.--Celticecis semenrumicis, C. ramicola, and C. ovata are distinguishable mainly from their galls. Galls of all three species are usually found attached to twigs. Those of C. semenrumicis ultimately develop distinct wings, are hairless, have a slender, curled apex, dehisce by early summer, and are known from the Mississippi Basin and Texas. Galls of C. ramicola have the same general distribution, are also hairless but never winged, have a short, straight apical extension, develop in late summer and early autumn and are slow to dehisce, in some cases persisting through late autumn. Galls of C. ovata are not sympatric with those of the other two, are instead more northern and eastern and hairy and wingless.

Biological note.--Galls first grow to their full length and only then develop wings. In Louisiana galls were found as early as late April on only partly expanded leaves, already with second instars. By June 6 only third instars were present, and galls dehisced readily although a few galls with viable full-grown larvae were found as late as August.

Distr.--KS, LA, MO, TX

- Raymond J. Gagne, John C. Moser: (2013) The North American Gall Midges (Diptera: Cecidomyiidae) of Hackberries (Cannabaceae: Celtis spp.)^©

Reference: https://www.biodiversitylibrary.org/page/51467028#page/39/mode/1up