Predatory fungi are not uncommon in the upper Amazon basin. Cordyceps sp. are common within this range. The fungus kills the invertebrate host, one or more fruiting bodies sprout from the invertebrate's exoskeleton (stromatic clavae), and spores (ascospores) are swept away on air currents to infect new hosts. Stroma are prominent, erect, and mostly clavate with a distinct fertile apical portion and a fertile stipe according to the Atlas of Entomopathogenic Fungi (Samson et al. 1988). This was photographed on a night hike at the CICRA research center, Madre de Dios, Peru.