Feron tibiale Kinsey, 1937 comb. rev.

Gall (Fig. 440). Individual galls swollen, cylindrical, flaring at the broadened tip, covered with more or less crystalline processes, with a few broad filaments (chiefly at the base of each gall), with almost all of the fibers fine, hair-like. Galls clustered, forming a more or less solid and tangled mass up to 27 mm in diameter and 13 mm high. Purple rose and light brown when young, becoming light straw brown to russet, rosy brown, or dark brown with age (Kinsey 1937).

Biology. Only the asexual generation is known, which induces galls on section Quercus, subsection Leucomexicana oaks: Q. arizonica, Q. chihuahuensis, Q. deserticola (= Q. texcocana) according to Kinsey (1937); adults emerge mainly during January-February (Kinsey 1937). Quercus glabrescens, Q. glaucoides, Q. obtusata, and Q. rugosa are new host records for this study.

Two species described by Kinsey (1937), F. tostum and F. uterinum, are morphologically consistent with the series of specimens that Kinsey called F. tibiale. They simply represent geographical variants of that species and hence we synonymise the names in this study.

The conspecific status of the two morphological variants within this species (one with a smooth mesopleuron, the other having a mesopleuron with a transverse reticulated-carinated band) was confirmed using DNA sequence data. One individual from each of the two morphotypes was sequenced for cytb and ITS2; both individuals had identical sequences for both genes (GenBank accessions OQ446186, OQ446241, OQ448247–OQ448248).

Distribution. Mexico: Mexico City, Chihuahua, Durango, Querétaro (Kinsey 1937); also from the State of Mexico in this study.

Feron tibiale, n. sp.
Agamic form

Gall. — Individual galls swollen cylindric, flaring at the broadened tip, covered with more or less crystalline processes, with a few broad filaments (chiefly at the base of each gall), with almost all of the fibers fine, hair-like. The whole forming a more or less solid and tangled mass up to 27. mm. in diameter and 13. mm. high. Purple rose and light brown when voting, becoming light straw brown to russet, rosy brown, or dark brown with age.

Host. — Quercus texcocana. [deserticola]

Range. — Mexico: Mexico City, 25 E, 7000’ (types). .Mexico City, 12 W, 8500’ (galls). — Puebla: El Seco, 5 S\XZ, Extending from the Valley of Mexico southeast toward the state of Vera Cruz.

Life History. — Adults: December 5, 16. 23. January 10. February 25. March 2, 9, 10, 15. April 1, 10, 17. Most of the emergence in January and February.

This is the southernmost species yet known in the complex with 13-segmented antennae. Tibiale Is closely related to tecturnarum, which is the next species to the north and the most widespread species in Mexico.