Egg-sac-parasite
Guides
Philolema latrodecti
widow spider parasitoid wasp
Philolema latrodecti is a parasitoid wasp in the family Eurytomidae that specializes in attacking egg sacs of widow spiders in the genus Latrodectus. Originally described from Hawaii, it has been introduced to several regions as a biological control agent for invasive widow spiders. The wasp has been observed parasitizing brown widow spiders (Latrodectus geometricus) in French Polynesia and the Cook Islands, and the southern black widow (Latrodectus mactans) in Mexico. Infestation rates can be substantial, with one study finding the wasp in 31% of dissected brown widow egg sacs in Tahiti.