Giant Ichneumon Wasp
Large, thin-bodied wasp. Females are very dark black and yellow. They are parasitoids of wood-boring insects in dead, deciduous trees.When a female is ready to oviposit her eggs, she rotates segments 8 and 9 of her abdomen and unfolds her intersegmentary membranes so that they form a disc 2 cm in diameter. The surface of this disc produces a secretion that disintegrates the wooden substrate and facilitates her ability to insert her ovipositor. After she lays her eggs on the surface of the host larva she completes the same rotational movements to remove her ovipositor from the wood and the stylus returns to its resting position. This entire process takes an hour.
''Megarhyssa atrata'' is a species of large ichneumon wasp. It is known from North America, where it is found from Quebec, Michigan, Ohio and North and South Carolina to Florida. Adults are on wing from May to July. The larvae are parasitoids of the larvae of the woodwasp ''Tremex columba'' in dead deciduous trees.