Inocybe tauensis, a new species from the Samoan Archipelago with biogeographic evidence for a Paleotropical origin

Inocybe tauensis is described as a new species from the island of Ta’u, American Samoa. The species occurs in native littoral forest and is associated with the ectomycorrhizal tree Pisonia grandis. Based on an analysis of nLSU, RPB1, and RPB2 sequence data, I. tauensis appears to be derived from ancestors with a Paleotropical biogeographical distribution. Alternative explanations for the unexpected presence of an Inocybe species in the Samoan Archipelago are discussed.