Development of visual aids for the identification of the invasive pepper weevil from endemic weevil species in Northwestern Ohio

Nuris Acosta
Staff Researcher
Luis A. Canas

Pepper weevil (Antonomus euginii) Grant is a devastating pest in peppers. Detection of pepper weevils is based on finding the adults on lures sticky cards. However, pepper weevil resembles other endemic weevils in Ohio leading to false alarm among growers and unnecessary insecticides applications. Therefore, it is important for pepper growers to get a prompt and accurate identification of pepper weevil to avoid unnecessary control costs. Thus, this study aims to describe characteristics of adult's weevils that can assist with the identification process. We hypothesized that endemic weevils' species will be captured on sticky cards place on pepper fields. Yellow pheromone–baited sticky cards (TRECE® Pherocome) were placed around the perimeter of three fields in the Northwestern Ohio, just before pepper bud formed. After both side of the card was used, the cards were transported to the laboratory for examination and pictures of the weevils were taken with a SC 180 Olympus microscope digital camera. We found 9 types of endemic weevil. These weevils showed similar size and shape than pepper weevil. The shape and pattern of the scales, the scale directionality in the thorax, and the shape of the body and the snout were found to be some of the most notorious morphological features to differentiate endemic weevils from pepper weevil. These characteristics along with the pictures, should assist with a prompt identification process for the growers.

Key words: Pepper weevil, characteristics, scales, sticky cards.