Amanita viridissima (Amanitaceae, Basidiomycota), a striking new species from highlands of the semiarid region of Bahia, Brazil

Background - Amanita is a well-established genus by morphological, biochemical, and molecular data, in which most of the taxa are ectomycorrhizal. The generic characteristics are bilateral lamellar trama (in the agaricoid forms), longitudinally acrophysalidic stipe tissue and schizohymenial development. In the Brazilian semi-arid region putative ectomycorrhizal agaric or chanterelle species are infrequently reported. Amanita lippiae, Cantharellus guyanensis, C. rubescens and Lactarius rupestris were recently described for that region. Here, an additional, morphologically striking new species of Amanita is described from the 'Chapada da Diamantina' highlands of Bahia, Brazil. Methods - The new species was collected in a forest called 'mata de neblina' or 'mata nebular' (= misty forest), that occurs at elevations between 1650 and 1800 m a.s.l. in the region of Catoles. For morphological analysis standard methods for Amanita were followed. Key results - Amanita viridissima is described as new species from the Bahian semiarid highlands. It belongs to Lepidella subsect. Solitariae stirps Cinereoconia and is charactererized by the medium-sized green basidiomes, clampless basidia, pale subhymenium cells, pigmented universal veil and with elongate (but also sometimes cylindric in our case) basidiospores. Other two taxa of stirps Cinereoconia, Amanita odorata and A. pelioma also have green pigments, but differ in several features.