Studies on the biogeography of Phellinotus piptadeniae (Hymenochaetales, Basidiomycota): Expanding the knowledge on its distribution and clarifying hosts relationships

Abstract Phellinotus piptadeniae is associated with several hosts and presents a continental and disjunct geographic distribution, whose populations occur in both dry and wet forests of South America. To understand the distribution of P. piptadeniae, we explored the prior knowledge of its host geography to predict potential distribution of the fungus and discuss aspects of its geography. Based on records from public herbarium data of Piptadenia gonoacantha, the main host of P. piptadeniae, we confirmed its occurrence in four Brazilian states with no previous records. Also, the analysis of herbarium specimens from Brazil and Argentina revealed the presence of P. piptadeniae in one additional Brazilian state and its first record in Argentina. Our study showed the importance of using prior information of host distribution to clarify the P. piptadeniae distribution pattern. The most representative host of the fungus was Pip. gonoacantha (1117 records). Further, a high environmental concordance between P. piptadeniae and a contemporary Seasonally Dry Tropical Forest distribution map (~76% of the records) was observed. We discuss the current distribution pattern of P. piptadeniae, present evidence for Caatinga as an ancestral area of the Phellinotus lineage and the Vanishing refuge model as the probable process that shapes the natural history of the species.