Celticecis globosa Gagne, new species

Cecidomyia sp. Wells 1916: 273, Plate XVII, Fig 12a.

Hosts: Celtis laevigata, occidentalis

Gall.--Attached to leaf vein, usually on underside of leaf; ovate to globular, upright, often with lateral or encircling bulge near mid-length, apex flattened; light green, white to yellow, turning reddish, matte, hairless or, in most specimens from southcentral U.S. (Arkansas, Louisiana, Mississippi and Texas) covered with short pubescence not obscuring surface; ca. 3.0–3.5 mm long and 2.0–2.5 mm wide; apparent on opposite side of leaf as minute convexity; wall uniformly thin except at bulge when present, larval chamber ovate, shaped as for gall not including bulge.

Affinities. — See discussion under C. pubescens. [C pubescens and two others, C. pyriformis and C. wellsi, appear to be related. All three cause upright, columnar, woody, more or less hairy leaf galls that are attached to veins, Celticecis globosa may also be related to these three. The gall of C. globosa is also upright and woody but the larval chamber is ovoid instead of columnar and the larva itself is flatter and more deeply sulcate between segments.]

Biological notes.--The gall exterior is hairless (Fig. 22) or, in most specimens from Arkansas, Louisiana, Mississippi and Texas, fuzzy (Fig. 40). At the beginning of our study we kept these separate, but in the end we could find no other distinction between specimens of C. globosa from the hairy and non-hairy galls. This gall appears generally late in the season. In Alexandria, Louisiana, we noticed young galls with already developed second instars only in early July. These continued to develop long after galls of all other species except some C. pubescens were all mature. As late as September 25, some galls of C. globosa still contained second instars, although most contained third instars. By mid-October almost all galls contained third instars. Galls with viable third instars were still common on leaves on November 20, long after galls of most other species remaining on the leaves contained only dead larvae or parasitoids. In Kentucky, Ohio and Maryland, galls of C. globosa were also late, making it the most common gall collected in August and September. Larvae are usually white but some turn yellow to orange.

Distr.--This is a widespread species in eastern U.S. on both northern hackberry and sugarberry.

AR, FL, IA, KS, KY, LA, MD, MS, OH, TX, VA, WV

- 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/31/mode/1up