Genus Phallus Junius Ex L. (Phallales, Basidiomycota): New Occurrences, Checklist, and Identification Key for Brazil

The genus Phallus, popularly known as stinkhorns, includes representatives characterized by phaloid form, mucilaginous gleba with a passive dispersal mechanism of basidiospores associated to insects. In Brazil, the records of Phallus species are concentrated in the South and Southeast regions of the country, some identifications are mistaken, and studies are insufficient to estimate biodiversity of the genus. In this context, the present study aimed to contribute with two new Phallus records for Brazil, inventory Phallus species described for Brazil, and develop an identification key. Collections were conducted in the municipalities of Barbalha-CE (Parque Ecológico Municipal Riacho do Meio) and Crato-CE (Parque Estadual Sítio Fundão). The basidiomata collected were herborized, underwent morphological analysis, and were identified based on specific literature. The species P. squamulosus was identified, characterized by an unexpanded basidiome and volva with a scaly surface and white receptacle with shallow reticulations and a wide apical pore. This is the third record for science and the first for the Semiarid Northeast. After review of Phallus records for Brazil in the literature (articles and books), we concluded that there are 14 species of Phallus in Brazil. In the checklist of the genus Phallus, we have included synonymies, collections, type locality, GenBank information, records for Brazil, including state, city, biome, voucher used in the description, and reference. We also present additional information on the species: diagnostic characters, discussion, taxonomic problems, references for illustrations and description, DNA sequencing data deposited in GenBank, and information from Brazilian collections. The identification key for Phallus species recorded for Brazil was based on the macro- and microscopic characters of the basidiomata. The study will contribute to the taxonomy and systematics of the genus Phallus and will serve as a basis for new taxonomic studies and for the identification of new specimens collected in Brazil and other localities.