There is a fungus, Massospora cicadina, that attacks periodical cicadas[often called 17-year or 13-year locusts]. First, diploid resting spores infect cicadas just before they emerge, turning most of the abdomen into haploid spores while leaving the head and thorax intact. The cicadas remain active, but become ‘unnaturally sexually receptive’. Infected males even wing-flick at other males. causing frequent male-male attempts at copulation. Infected females cannot complete normal mating and keep wing-flicking at normal males until they die. Sexual contact, or more exactly pseudo-sexual contact [half the abdomen has fallen off], seems to be important in spreading the haploid spores.
In the second stage, the infected cicadas produce a mass of diploid resting spores, that fall to the ground and wait 17 years for the next set of victims.