The San Antonio Express-News is reporting that concerned scientists have put out an alert asking Texas landowners to keep a lookout for the invasive cactus moth (Cactoblastis cactorum) whose arrival in Texas is apparently imminent. The moth, which originates from South America, is a threat to native prickly-pear cacti (Opuntia spp.), and in fact has been used as a biological control in other parts of the world where prickly-pear cacti are considered invasive. Cactus moths were discovered in the U.S. in the late 1980s, and have been spreading both from Florida westward and from Mexico northward. If you're in Texas and you think you've spotted the moths or the caterpillars of this species, you should contact Texas Cooperative Extension (I can't find a related webpage - more information can be found here (.pdf), or call Barron Rector at 979-845-2755).