Hawaii's unintended beetle became the only successful introduction

Representative Image of diverse Calosoma beetle species with a focus on their failed introductions to Hawaii (AI Generated Image) For six decades, scientists repeatedly introduced predatory beetles to Hawaii in an effort to control crop-damaging caterpillars, but none of the intentionally released species established a lasting population. A study published in Biological Control titled Calosoma (Coleoptera: Carabidae) biological control introductions to Hawaiʻi: Taxonomic ignorance and confusion lead to an unexpected result documents 13 introductions of beetles from the genus Calosoma between 1897 and 1957. The beetles were brought in as predators of nutgrass armyworm, armyworm and lawn armyworm. Researchers examined museum specimens, archival field notes and published records and identified eight flight-capable Calosoma species involved in the failed introductions. The only Calosoma species currently resident in Hawaii is Calosoma anthracinum, a rarely collected Mexican beetle that was never intentionally introduced. The researchers say it appears to have arrived accidentally in a mixed shipment of beetles.Calosoma beetles were introduced to Hawaii 13 times between 1897 and 1957The...