Callirhytis clavigera (Ashm.)

Quercus cinereae [incana], laurifolia, phellos
Stem galls, woody stem swellings
A horned knot gall but the horns do not drop out. Described from Quercus laurifolia.

Quercus myrtifolia
Stem galls, woody stem swellings
Callirhytis cornigera or Callirhytis clavigera. A horned knot gall.

[Photo caption]
On Q. phellos (horns have been broken off in photo). Also on Q laurifolia, myrtifolia. Adults emerged Feb. 14-21 (TX).

Cynips quercus clavigera n. sp.

Galls.--Abrupt, irregular, woody, tuber-like swellings, varying greatly in size, from a half to an inch and a quarter long by almost the same in width, attached to the terminal twigs and branches; externally (at the beginning of the season), it is smooth and resembles very much the gall of Cynips q batatoides, but later in the season it becomes rough with deep fissures, through which issue spiny, succulent tubes, which secrete a sticky honey-like substance; internally, at first it is white and soft but becomes brown and hard with age; the tubes are thickened at base in the centre of which the larva resides.

Andricus clavigerus O.S.
Agamic form, clavigerus OS

Irregular, ovoid, horned, woody twig or branch galls, dia 1-3 cm.

Adults in May

On Q phellos

Callirhytis quercusclavigera (Ashmead 1881)

Hosts: Quercus inopina, myrtifolia

[Asexual generation stem swelling galls found in Florida in the spring.]