[Originally published in the Summer 2022 issue of the UC IPM Green Bulletin]

The three-lined cockroach, Luridiblatta trivittata, (Figure 1) is the smallest cockroach species in California, with adults averaging only 5–7 mm in length. This newly introduced cockroach is native to North Africa and the Eastern Mediterranean. It was first detected in California around 2004 in Marin County, but it was not positively identified until 2009. Since then the three-lined cockroachhas slowly expanded its range to include the entire San Francisco Bay Area, south to San Luis Obispo, east to the foothills of...