Philonix gigas

Quercus lyrata
Leaf galls, detachable
Globular, 15-20 mm in dia, with a thick wall and pubescent surface, dropping in the fall.

Quercus macrocarpa
Leaf galls, detachable
Globular, 15-20 mm in dia, surface covered with a fine pubescence, dropping in early Sept. (Ft Worth, TX)

[Photo caption]
On Q lyrata. Also on Q macrocarpa. Adults emerged Dec 1 and Dec 15 after -14 F. More were found dead in breeding cage in March.

Philonix gigas, new species

Host: Quercus lyrata

Gall. — Globular, 15-20 mm. in diameter, produced on the under side of leaves and dropping to the ground in the fall. In appearance and structure they resemble the much smaller galls of Philonix nigra (Gillette).

Habitat. — The type galls were collected at Hoxie, Arkansas. Seven flies emerged December 1, 1917; three December 18, 1917; and two March 24, 1919. From galls collected at Poplar Bluff, Missouri, three adults were cut out November 16, 1917.

Cynips (fulvicollis) gigas (Weld)
agamic form

Philonix gigas Weld, 1922, Proc. U.S. Nat. Mus. 61 (18): 12, fig. 2.
Cynips fulvicollis gigas Kinsey, 1930, Ind. Univ. Studies 84-86:259, figs. 40, 229, 241, 250. Houard, 1935, Marcellia 28:126.

To the data given in Kinsey 1930, add:

RANGE.-Missouri: Kansas City (galls, Q. Michauxii). See Figure 120.

LIFE HISTORY. —Galls immature on August 14.

Cynips fulvicollis var gigas
agamic form

Philonix gigas
Philonix nigra err det Weld

GALL. — As described for the species, larger than other varieties; prominently pubescent; up to 20.0 mm. in diameter; on the leaves of Quercus lyrata, Q. Michauxii, and Q, Muhlenbergii. Figure 229.

RANGE. — Arkansas: Hoxie (Weld, Q. lyrata, types). Missouri: Poplar Bluff ( Q . lyrata, acc. Weld 1922). Kansas: Manhattan and Holton ( Q . Muhlenbergii acc. Weld, 1926). Riley County (Marlatt in Kans. Agric. College and Kinsey coll.). Arkansas City ( Q . Michauxii, R. Voris in Kinsey coll.). Winfield, Cedarvale, Silverdale, and Dexter ( Q . Michauxii, Q. Miihlenbergii, R. Voris in Kinsey coll.). Probably confined to Q. lyrata and to chestnut oaks, in the Ozark area and its immediate extensions. Figure 40.

This is an Ozark variety which seems to be isolated from varieties major and vorisi of the same region by its host relations. The types of gigas came from Q. lyrata and I have many insects that appear to represent the same variety from Q. Muhlenbergii and Q. Michauxii. Gigas is closely related to major and vorisi, and occasionally the host restrictions fail and the three hybridize in eastern Kansas. Weld was correct in recognizing lanaeglobuli, from Q. bicolor in Florida, as another relative of gigas.

Weld found pupae in the galls on October 10 (in 1917) ; he found live adults in the galls on November 16. The Marlatt material from Riley County, Kansas, was bred in November and January. Weld’s material bred out-of-doors at Evanston gave eight adults on December 1 and three more on December 18, the thermometer having registered — 14° F. between those dates. He found other adults emerging in the next spring, and suggests that “emergence must be distributed over at least two or three seasons, for normal larvae were found when the last of the galls were cut open December 2”, more than two years after collecting. Almost all of the insects I have bred emerged in the first winter after collection, only two emerging the second year in my breeding bags. My records for emergence are December 17, 20, 22, 28, and 24 ; January 4, 5, 7, and 9; and February 6.