Animated coloured scanning electron micrograph (SEM) of Nut weevil head (.). Curculio is genus of weevil (beetle) in the family Curculionidae. These weevils are referred to as acorn or nut weevils. They attack the seeds of trees such as oaks and hickories. They are consider an important agricultural pest. The adult female weevil bores a small hole in the immature nut to lay her eggs. The eggs then hatch into legless grubs. The grubs bore holes through the shells (from the inside) to emerge into the soil. They usually live for a year or two in the soil before maturing into adults.