Report of Astaena pygidialis Kirsch (Coleoptera: Scarabaeidae), the Main Chafer Beetle Causing Damage to Avocado Fruit and Young Leaves in Antioquia Department, Colombia

Abstract

Scarab beetles (Coleoptera: Scarabaeidae) are one of the most limiting pests of avocado in Antioquia Department, Colombia. The establishment of management strategies to control these beetles has been difficult because the species causing damage to avocado fruit and young leaves have not been identified. Selected commercial avocado fields were surveyed at different times of d for scarab beetle adults affecting small fruit and young leaves, as well as other plant structures such as flowers, tender buds, stems, and mature leaves. Additionally, ultraviolet light traps were placed at each field to quantify the species captured. After direct scouting of avocado trees, the only scarab beetle species detected causing damage to fruit and young leaves at all sampling sites was Astaena pygidialis Kirsch (Coleoptera: Melolonthinae). Adults were observed chewing the green skin of small fruit causing striations on the fruit and skeletonization of young leaves by chewing the leaf tissue between veins on the upper surface. Other species observed include Anomala cincta Say (Coleoptera: Rutelinae), Charioderma xylina Blanchard, and Strigoderma sp. (all Coleoptera: Rutelinae) associated with flowers, Isonychus sp. (Coleoptera: Melolonthinae) with flower buds, Cyclocephala fulgurata Burmeister (Coleoptera: Dynastinae) with tender buds, stems and flowers, and Astaena valida Burmeister and Plectris pavida (Burmeister) (both Coleoptera: Melolonthinae) with mature leaves. The species detected through scouting also were captured with light traps. The dominant species captured with light traps was Phyllophaga obsoleta (Blanchard) (Coleoptera: Melolonthinae), which was not observed causing damage to avocado fruit or young leaves. Correct identification of the species is the key to establish adequate sampling and management strategies for these scarab beetles in avocado crops.