Atrusca dugesi (Mayr, 1886)

Figs 249–261

Synonymy
Dryophanta dugesi Mayr, 1886: 370.
Cynips (Atrusca) dugesi (Mayr): Kinsey 1930: 278, female, gall.
Cynips dugesi variety dugesi (Mayr): Kinsey 1930: 281, female, gall.
Cynips dugesi dugesi (Mayr): Kinsey 1936: 109, female, gall.
Atrusca dugesi (Mayr): Pujade-Villar, 2009: 818.

Types examined

According to Melika & Bechtold (2001) Mayr’s type of Dryophanta dugesi was not found in the Mayr collection at the Natural History Museum in Vienna where the collection is deposited.

Material examined

Two females “San Felipe, Gto 8000’, 20Sw, Mex., gall 12.7.31, 7 females 2.15.32”, “Q. jaralensis Kinsey coll.”, “Cynips dugesi Kinsey det. ‘33”, deposited in the general collection in AMNH, NYC, examined by GM.

Gall (Fig. 261)

The gall is similar to galls of Kinsey’s bella and dugesi complexes. Mature galls rosy tan, unspotted, weakly shining, up to 21 mm, in average 17 mm in diameter. The gall pic from https://www.gallformers.org/gall/3392 by Juan Carlos López Domínguez on Q. microphylla.

Biology

The asexual generation is only known to induce leaf galls on Q. jaralensis [syn. of Quercus potosina], Q. microphylla. Galls mature in autumn; adults emerge in February–March next year.

Distribution

Mexico: Guanajuato.

Cynips (dugèsi) dugèsi (Mayr)
agamic form

Dryophanta Dugès i Mayr, 1886, Verh. zoo.-bot. Ges. Wien 36:370, pl. 12 fig. 1a, 1b, 2. Mayr, 1902, Verh. zoo.-bot. Ges. Wien 52:290. Dalla Torre and Kieffer, 1902, Gen. Ins. Hymen. Cynip.: 52.
Dryophanta dugesii Dalla Torre, 1893, Cat. Hymen. 2:50.
Dryophanta Dugesii Kieffer, 1901, André Hymen. d’Europe 7 (1):621.
Diplolepis dugesi Dalla Torre and Kieffer, 1910, Das Tierreich 24:344, 355, 811; figs. 76-77.
Dryophanta Dugesi Küster, 1911, Die Gallen der Pflanzen: 170.
Dryophanta dugesi Beutenmüller, 1911 (in small part only), Bull. Amer. Mus. Nat. Hist. 30:345, pl. 12 figs. 6-7. Felt, 1918, N.Y. Mus. Bull. 200:98, fig. 97 (6-7).
Cynips dugèsi dugèsi Kinsey, 1930 (in small part only), Ind. Univ. Studies 84–86: 281-282.

GALL.-Similar to all galls of the C. bella and C. dugèsi complexes. Mature galls rosy tan, unspotted; weakly shining; of moderate size, up to 21. mm., averaging nearer 17. mm. in diameter. Figure 71.

Original description Translation: The gall, which is produced by an as yet undescribed species of cynipid, is found on Quercus mexicana Humbolt and Bonplandt, and belongs to that group of American leaf galls which are connected with the under surfaces of the leaves only by a single point, have thin walls, and show in cross-section a central, egg-shaped larval cell from which radiating threads go to the inner surfaces of the outer walls of the gall. It is entirely spherical and measures 6. to 15. mm. in diameter; has a very thin wall which is for the most part not shining, largely a beautiful red in color, in part light yellow, or even with a light yellow ground finely marbled red; in the early stages it is covered with soft and short downy hairs which later must fall off because of the interference of the enlarging galls with each other or through rubbing. By cutting open the gall, one sees numerous, very fine, radially placed hairs extending from the centrally-placed, monothalamous larval cell to the outer wall, while, for instance in the galls of Dryophanta bella Bassett and D. polita Bassett these hairs are not very numerous and more or less fine. If one directs the cut through the new species so that it does not go through the larval cell, one may never or rarely see the cell because of the many hairs arising from it (see the illustration showing the cross-section of the gall).

HOST.S.–G) wercus microphylla, an alpine, dwarf white oak. Less often on Q. jaralensis, a scrub white oak. Not on the black oaks, Q. mexicana or Q. hypoleuca to which the types were mistakenly ascribed.

RANGE.-Guanajuato: León, 20 NE, 9000' (Q. microphylla, Q. jara lensis). San Felipe, 20 SW, 8000' (Q. fara lensis). Type locality not known, but probably from near León. Chiefly restricted to the alpine dwarf oak, Q. microphylla, in that por tion of the Western Sierra of Mexico which centers in Guanajuato. Figure 18.

LIFE HISTORY..—Adults: February 15, 16, 20. March 2.

All previous determinations of insect and gall material as Cynips dugèsi (in Beutenmüller 1911, Kinsey 1930, etc.) prove to have been incorrect. Through the courtesy of Dr. F. Maidl of the Vienna Museum I have now been able to examine a type insect and galls, and discover dugèsi to be an insect which we, in our own collections, found nearly confined to the little alpine dwarf, Q. microphylla, in the high mountains which lie northeast of León, in the Central Mexican Sierra. The twigs and leaves with the type galls have been variously mis-determined as belonging to the black oak, Quercus mexicana, or to the black oak, Q. hypoleuca ; but to one who has studied Mexican oaks in the field they are unmistakably those of Quercus microphylla, the same host on which we found the insect. Although the type collection was without locality record, other than “Mexico,” Dr. Dugès lived in León, and it is not improbable that his collections were made in the same high mountains from which we collected the species just northeast of León. We also have the insect from nearer San Felipe, also in the state of Guanajuato, but found it nowhere outside of that state.

Practically all of the insects bred from all of the other oaks which occur in the Sierra near León represent Cynips (dugèsi) vulgata, but a few of the insects from the scrub oak, Q. jaralensis, prove to be C. dugèsi, indicating that the host isolation which normally segregates dugèsi on Q. microphylla may, on occasion, break down. No species of the C. bella complex occurs anywhere near the area in which dugèsi is found.

Cynips dugesi variety dugesi
agamic form

Dryophanta dugesi
Diplolepis dugesi

GALL. — As described for the species, galls thus far collected being rather small (up to 15.0 mm. in diameter), with dull surfaces; on leaves of Quercus mexicana and other white oaks.

RANGE. — Mexico: San Luis Potosi (Ed. Palmer, in M. C. Z. and Kinsey coll.). Mts. of Guana juanto (Duges in U.S.N.M.). Probably confined to an area in more central Mexico. Figure 44.

Mayr gave Q. mexicana as the host of the type material, and his illustration more nearly matches mexicana than the black oak, hypoleuca, to which Beutenmiiller referred it. My specimens were on an oak more closely related to Q. oblongi- folia (which it is not). If Mayr’s host reference is correct, then mexicana is a white oak arid not a black oak as Trelease lists it (Nat. Acad. Sci. Mem. 20 :173) .