FIRST RECORD AND BIOLOGICAL OBSERVATIONS ON THE WOODWASP Sirex obesus BRADLEY IN AGUASCALIENTES, MEXICO

The woodwasp Sirex obesus Bradley is described from specimens fortuitously captured in Lindgren funnel traps used in studies on the flight of the bark beetle Dendroctonus mexicanus Hopkins and through the direct capture on the bark of trees, in the municipality of San Jose de Gracia, Aguacalientes, Mexico. Pinus leiophylla Schl.et. Chain. and Pinus teocote Schl. et. Chain., weakened by the presence of D. mexicanus, were identified as hosts of S. obesus. The adults of this species emerge and oviposit during October and November. As parasitoids of S. obesus, some specimens of Ibalia leucospoides Hochenwarth (Hymenoptera: Ibaliidae) were collected in the same pine sections where the specimens of S. obesus emerged. This is the first record of the species in the state of Aguascalientes; therefore, more attention should be given to this insect because of its potential risk of invading pine trees and stands in Mexico.