Cynips torosa, comb. rest.

Cynips (plumbea) torosa, new species
Agamic form

GALL.—Large, spherical, rarely flattened on a small base, not pointed ; dull, slightly shrivelling, with a conspicuous, moderately heavy scurf (stellate pubescence) which is so persistent that even old galls are conspicuously bluish gray ; denuded surfaces of galls light tan to dark purplish brown; up to 9.5 mm., averaging near 7.0 mm. in diameter.

HOSTS. — Quercus rhodophlebia [rugosa] (types) ; Q. texcocana [deserticola]. These are the two largest trees among the oaks of the region.

RANGE.—Mexico : Mexico City, 22 E, 8200' (Q. rhodophlebia, Q. texcocana). Puebla: El Seco, 19 NE, 8500' (Q. rhodophlebia, types). El Seco, 5 SW, 8200' (Q. texcocana). Apparently restricted to the mountains east and southeast of Mexico City, ranging possibly into the state of Vera Cruz. Replaced south and west of Mexico City by C. texcocana Kinsey.

From several points in the mountains south and west of Mexico City we have C. (plumbea) texcocana (see Kinsey 1936, Ind. Univ. Sci. Ser. 4:205). From collections made 15 miles east of Mexico City, in January, 1932, we obtained three insects which look like good texcocana; but from the more extensive collections made 22 miles east of Mexico City in December, 1935, and from our collections made in the more south- eastern state of Puebla we get a different insect, the present species torosa. The galls of texcocana and torosa are practically identical, but the insects are so different that there seems no chance of error in our determinations; and we must conclude that the more eastern and more western species meet in the Valley of Mexico, or else that our earlier record for texcocana from east of Mexico City involved some error in data. We have several other cases of cynipid groups represented by different species on the two sides of the Valley of Mexico.