Celticecis oviformis (Patton)

Cecidomyiaceltis oviformis
Cecidomyia oviformis

Hosts: Celtis laevigata, occidentalis

Gall.--Usually along twig, occasionally on petiole or major veins of upper side of leaf, most often in groups; evenly spherical beyond obtuse, often weakly lobed base, with short apical nipple; green, turning brown, uniformly short-fuzzy but hairs not obscuring matte surface; 5–6 mm long, 4–5 wide; connection to host a prominent, circular, flat, persistent brown callus nearly 1/2 as wide as gall base; when on leaf apparent on opposite side of leaf as a thickening of vein; wall of uniform thickness throughout, larval chamber spherical, of same shape as gall.

Biological notes.--Galls of this species have a similar shape to those of C. connata when those of the latter are not found in aggregate, but galls of C. oviformis are covered with fine pubescence and are uniformly thin-walled, unlike galls of C. connata that are hairless and have thick walls of irregular diameter. Galls of C. oviformis develop and dehisce early in the season, possibly why it was not collected more often. In mid-April when galls were first noticed in Alexandria, Louisiana, they already contained second instars. After mid-May galls of this species still found attached to the host were parasitized.

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

FL, IL, KS, LA, MD, MO, OH, WV, TX

Celticecis oviformis New Combination

Cecidomyiaceltis oviformis

Celticecis oviformis

Celticecis oviformis was found at three study sites in Pennsylvania and one site in New Jersey (Figure 7). This study expands the range of C. oviformis into Pennsylvania and New Jersey, representing two new state records for this species.

[No name given; species later named Cecidomyiaceltis oviformis by Patton]

30. Cecidomyidous galls on the tender twigs, either singly or placed in rows of two or more specimens ; occurring also singly on the petiole or on the lower surface of the leaf. Gall usually resembling somewhat a large egg of some diurnal Lepidopteron; short, conical, or subglobular in outline, arising from a circular, truncate base, rounded off at tip where it is furnished with a short spine or nipple; surface dark green, opaque, granulose, usually with faint and shallow longitudinal furrows and usually hirsute with short stout hairs; sides at the base with more or less distinct, irregular protuberances. The gall is not entirely sessile, but only connected with the twig at the central part of its base. A vertical section shows a single spherical cell (rarely two) having a thick whitish yellow, hard and woody wall. Average height of gall 4 mm (excluding the apical spine); average diameter at base 3.4mm. The gall varies in shape, some specimens being more conical, others nearly globular or even slightly depressed at tip, while others are not hairy and less opaque, the surface being covered with little pustules. The latter form possibly constitutes a distinct species.

14. Cecidomyia sp.

A large, globular, mucronate tipped gall of the stem. 5-8 mm. dia. Base varies toward a truncate condition in some specimens. Green throughout the summer; finely pubescent. Chamber large, spherical. A thin membrane is constructed by the larva across the distal end of the chamber. Protective layer thick, nearly half as thick as the wall. Does not extend to apical canal. Nutritive layer relatively thin. The fibro-vascular bundles traverse the protective layer.

Riley describes a globular gall, which on "detaching the gall, the base is seen to be truncate and attached to the rib of the leaf by an extremely short, conical style, which is not visible from the sides. Average height, 3.5 mm., dia. at middle, 3.5-4 mm." See No. 32 in Riley's list [Celticecis pubescens]. This gall might be interpreted as an immature specimen of the above [Wells' Cecidomyia sp 13, Celticecis pyriformis]. Sear's number 34 is a variation of the above with the basal one-third developing low irregular ridges.