Taking care of the enemy: egg predation by the Darwin wasp Tromatobia sp. (Ichneumonidae) on the cobweb spider Chrysso compressa (Araneae, Theridiidae)

Some wasp species use spiders as food resources, overcoming several anti-predator barriers that are exerted by spiders. Tromatobia ichneumonid wasps spider egg predators usually attack Araneidae species, although there few records of predation on Clubionidae, Philodromidae, Linyphiidae, Tetragnathidae, and Theridiidae Here, we describe the interaction between sp. Chrysso compressa , a subsocial theridiid exhibits extended maternal care, in Atlantic Forest southeastern Brazil. We observed larva develop inside sacs C. preying entire mass building cocoons change color morphology sacs. Despite these structural modifications, registered an adult female guarding caring for (attacked sac) if they were offspring (non-attacked sac). To best our knowledge, this study represents first record eggs.