# First Report of Cactus Weevil Feeding on Selenicereus undatus in Jalisco, Mexico

## TL;DR

This paper reports the first observation of a cactus weevil feeding on and damaging wild pitahaya plants in Mexico, highlighting a new threat to this economically important crop.

## Contribution

The first documented report of Cactophagus spinolae feeding on Selenicereus undatus in the wild, establishing it as a reproductive host.

## Key findings

- Cactophagus spinolae was found feeding on Selenicereus undatus, damaging stems and flower buds.
- Nine eggs, nine larvae, and sixteen adults were observed, confirming S. undatus as a reproductive host.
- The study highlights the threat of C. spinolae to pitahaya crops in Jalisco, Mexico.

## Abstract

The cactus Selenicereus undatus (S. undatus), known as pitahaya or dragon fruit, is one of the pitaya species of economic importance for different countries worldwide, particularly in China, Mexico, Australia, Vietnam, Indonesia, and the United States, among other countries. On the other hand, Cactophagus spinolae (C. spinolae) is a pest insect found in Mexico, known as the cactus weevil or borer. This study reports, for the first time, C. spinolae feeding and damage to the vascular stem and flower bud of wild S. undatus plants in Jalisco, Mexico. Field sampling was conducted in wild populations of S. undatus between July and October 2024. The results of our study confirm that C. spinolae actively feeds on S. undatus, causing damage to the plant, primarily to the vascular cylinder of mature and immature stems, as well as to flower buds and tissues. During monitoring, we observed a total of nine eggs, nine larvae, and sixteen adults in different plant samples, confirming that S. undatus serves as a reproductive host for C. spinolae. The results highlight the threat of C. spinolae to S. undatus in the State of Jalisco, which highlights the need to incorporate new agricultural strategies to mitigate the impact that this insect has on pitahaya.