Monomachus sp. ♀️

 

Monomachus is a genus of parasitoid wasps within the family Monomachidae (superfamily: Diaprioidea), known for their distinctively long, sickle-shaped metasoma in females and large mandibles in both sexes. Found in the Southern Hemisphere (Neotropics, Australia, New Guinea), these 9.5-11.2 mm wasps act as parasitoids, particularly targeting Stratiomyidae (Diptera) fly eggs and larvae. Monomachus wasps exhibit strong sexual dimorphism. Females possess an elongated, slender, and curved metasoma (abdomen) designed for oviposition, while males have a more pedunculate, thinner abdomen. Both sexes feature unique, often large mandibles. They are primarily found in the New World tropics (especially Brazil's Atlantic rainforest) and in Australia/New Guinea. They are notably absent from New Zealand. They are parasitoids of Diptera (flies), specifically in the subfamily Chiromyzinae (Stratiomyidae). Monomachus antipodalis in Australia has been known to parasitize Boreoides species, while South American species have been reared from Chiromyza vittata. Monomachus prefer high-altitude, cool areas, often found in cloud forests or temperate areas of the Southern Hemisphere. They are often collected in Malaise traps. The family has historically been linked to Proctotrupoidea but is now often placed within the superfamily Diaprioidea. There are over 23 species of Monomachus known from the New World and several from the Australia/New Guinea region. Monomachus are generally considered rare or hard to capture, though they can be found in higher numbers in specific locations, such as Brazil's Atlantic rainforest in the cooler months.