D3547: New records and recommended methods for detecting the introduced two-spined trap-jaw ant (Odontomachus haematodus) in the Southeastern United States

The two-spined trap-jaw ant, Odontomachus haematodus (Linnaeus), is a ground-nesting ant native to South America that has been introduced to the Southeastern United States. Although the earliest records of this species in the continental US date back to over 60 years ago, a long period of misidentification as a native congener has limited our understanding of the spread of this species across the Gulf South. Although the most current published literature indicates that the introduced range of O. haematodus is limited to urbanized coastal regions of Mississippi, Alabama, and Louisiana, citizen science observations suggest recent expansion. Before large-scale systematic surveys can be conducted, best practices for surveying this species need to be established. We conducted a multi-method survey of urban parks and private properties in and around Hattiesburg, Mississippi to 1) assess the degree of O. haematodus occurrence in the Hattiesburg area, and to 2) identify the most effective survey method for detecting O. haematodus in urban areas. We report high abundance of O. haematodus in Hattiesburg, the northernmost & inland most reported occurrence of this species to date. We go on to recommend best practices for future surveys and discuss newly developed hypotheses for future work seeking to develop effective management approaches for controlling this species across its introduced range.