Population structure of Guyanagaster necrorhizus supports termite dispersal for this enigmatic fungus

Understanding dispersal mechanisms—the movement of propagules—can shed light on how organisms are adapted for their ecosystem. Guyanagaster necrorhizus is a sequestrate fungus, meaning its dispersal propagules, or spores, are entirely enclosed within a fruiting body, termed a sporocarp. This fungus is most closely related to Armillaria and its allies. While Armillaria species form mushrooms with forcibly discharged spores, G. necrorhizus spores have lost this ability, and by necessity, must be passively dispersed. However, G. necrorhizus does not possess characteristics of other sequestrate fungi with known dispersal mechanisms. Repeated observations of termites feeding on G. necrorhizus sporocarps, and spores adhering to their exoskeleton, led to the hypothesis that termites disperse G. necrorhizus spores. To test this hypothesis, we used microsatellite markers and implemented population genetics analyses to understand patterns of clonality and population structure of G. necrorhizus. W...