The students excitedly came in after catching this fly. “It has a massive stinger on it!” one said. I explained that it didn’t look like a stinger and that it was probably an ovipositor, making it a female insect.

Results

Billy Bob Bart ended up being a Robber fly called Efferia aestuans (EOL). Robber flies (or assassin flies) are notorious for predating other insects. They ambush from below to take them out in the air while flying. These are good to have around since they take out the nuisance species.