The male of Hymenoepimecis japi (Hymenoptera, Ichneumonidae, Pimplinae) is described and illustrated. The specimen was collected in a modified web (cocoon web) of Leucauge roseosignata (Araneae, Tetragnathidae) made in a laboratory. Both, host and parasitoid were collected in Reserva Biológica Serra do Japi, located in Jundiaí, São Paulo, Brazil.

The entomopathogenic fungus Ophiocordyceps camponoti-atricipis parasitizes the ant species Camponotus (Myrmothrix) atriceps in the Brazilian Central Amazon, and may induce behavioral changes in its hosts. In this study, we extended the distribution range of this interaction for the Atlantic Forest biome. In addition, we investigated the occurrence of parasitized ants fixed upon specific host plants, plant structures and heights above the soil. We found higher frequencies of ants on the introduced plant of commercial value Coffea arabica. The ants adhered to the plants using their mandibles, normally on the abaxial surface and central veins of leaves. The fungus killed its hosts preferentially at a height of 1 m to 2.5 m above the soil, differing from that observed in other studies.