Giant ichneumon wasp and mystery visitor By Matt Young September 14, 2020 11:00 MST Photograph by Mark Sturtevant. Photography Contest, Runner-up. Megarhyssa atrata, giant ichneumon wasp. The photographer writes, "This large female ichneumon wasp is using her long ovipositor to drill into wood in order to lay an egg on a wood-boring sawfly larva. The smaller wasp riding her is probably a male in the genus Rhysella, and he appears to be mightily confused about his prospects for mating and passing on his genes."