Andricus rochai (agamic)

Andricus rochai Pujade-Villar n. sp. 

Gall (Figs. 4a-d) Globular (8-12 mm, n = 25), pedunculate (3-10 mm), gregarious (forming groups of more than 10 galls) and deciduous. Located in the main leaf vein (Fig. 4b) or at the end of the shoots (Fig. 4a), which thicken, in which depressed and circular insertion points are observed (Figs 4a-b). First green, then reddish, and finally brown. Centrally located larval chamber (2mm diameter), separated from the outside by a spongy colored tissue chestnut at maturity (Figs. 4c-d).

Host: Quercus laeta Liebm. (Section Quercus, white oaks), endemic to Mexico distributed in multiple states (Aguas Calientes, Coahuila, Durango, Guanajuato, Hidalgo, Jalisco, Mexico, Michoacan, Nayarit, Nuevo Leon, Oaxaca, San Luis Potosí and Zacatecas) as indicated by Valencia-A (2004)

Biology. Only agamic females are known. At the end of June 2016 hundreds of galls were detected in the soil. In 2017, these were observed in the buds of the trees at the end of May-early June. Adults emerged in January of the following year. In February 2018, in sheets formed the previous year, gills adhered to the venation were observed main leaves, inside the galls there were mature larvae and pupae; so this agamic form is capable to attack two different organs in oaks. The galls are easily dropped upon contact or vibration from the wind. The sexual form is unknown, but it must have rapid development between January-April. Parasitoids (Pteromalidae and Eurytomidae) were obtained in two phases, the first from July to December (before the emergence of the cynipids) and the second from second after said emergency. 

Distribution Mexico (Mexico City).

Descripción de una nueva especie de Andricus Hartig de México (Hymenoptera: Cynipidae: Cynipini)