Ichneumon is a genus of parasitic wasps in the family Ichneumonidae. Megarhyssa greenei is a species of large ichneumon wasps. Mastrus ridens is a species of ichneumon wasp. Megarhyssa atrata is a species of large ichneumon wasp. Insects in the family Ichneumonidae are commonly called ichneumon wasps, or ichneumonids. The ovipositor of the giant ichneumon wasp is the longest egg-laying organ known among biologists. Megarhyssa nortoni (common name western giant ichneumon) is a species of large ichneumon wasp. Flies in this family have elongated bodies and resemble ichneumon wasps in shape. Netelia is a genus of ichneumon wasps in the family Ichneumonidae. "P. alcon" larvae are sought underground by the "Ichneumon eumerus" wasp. Hercus fontinalis is a species of ichneumon wasp in the family Ichneumonidae. The Ichneumon wasp "Dirophanes invisor" is a parasitoid which specializes on "T. viridana". They may also be parasitized by ichneumon wasps, "Bathylplectes anurus" and "B. curculionis". In 1811, Johann Karl Wilhelm Illiger subsumed the ichneumon to the genus "Herpestes".