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Ectomycorrhizal fungi (ECM) sustain nutrient recycling in most terrestrial ecosystems, yet we know little about what major biogeographical events gave rise to present-day diversity and distribution patterns. Given the strict relationship between some ECM lineages and their hosts, geographically well-sampled phylogenies are central to understanding major evolutionary processes of fungal biodiversity patterns. Here, we focus on Amanita sect. Vaginatae to address global diversity and distribution patterns. Ancestral-state-reconstruction based on a 4-gene timetree with over 200 species supports an African origin between the late Paleocene and the early Eocene (ca. 56 Ma). Major biogeographic "out-of-Africa" events include multiple dispersal events to Southeast Asia (ca. 45-21 Ma), Madagascar (ca. 18 Ma), and the current Amazonian basin (ca. 45-36 Ma), the last two likely transoceanic. Later events originating in Southeast Asia involve Nearctic dispersal to North America (ca. 20-5 Ma), Oceania (Australia and New Zealand; ca. 15 Ma), and Europe (ca. 10-5 Ma). Subsequent dispersals were also inferred from Southeast Asia to East Asia (ca. 4 Ma); from North America to East Asia (ca. 11-8 Ma), Southeast Asia (ca. 19-2 Ma), Northern Andes (ca. 15 Ma), and Europe (ca. 15-2 Ma), respectively; and from the Amazon to the Caribbean region (ca. 25-20 Ma). Finally, we detected a significant increase in the net diversification rates in the branch leading to most northern temperate species in addition to higher state-dependent diversification rates in temperate lineages, consistent with previous findings. These results suggest that species of sect. Vaginatae likely have higher dispersal ability and higher adaptability to new environments, in particular compared to those of its sister clade, sect. Caesareae. Overall, the much wider distribution of A. sect. Vaginatae, from pan-tropical to pan-arctic, provides a unique window to understanding niche conservatism across a species-rich clade

The members of Amanita sect. Phalloideae (Fr.) Quel. are responsible for many fatalities worldwide. However, some species in this section have previously been reported as non-lethal and lacking deadly toxins. Sequences of five genes (ITS, nrLSU, RPB2, TEF1-alpha, TUB2) of species belonging to the section from tropical Africa, America, Asia, Australia, and Europe were included in this study to elucidate the phylogenetic relationships among the species. The results indicated that the lethal species are in one clade (subclade I) while the non-lethal species are divided into two clades (subclades II and III) within the section. Moreover, two non-lethal species from tropical Africa, namely A. ballerinoides and A. bulbulosa are newly described based on both morphology and molecular approaches. Phylogenetically, they cluster in the same subclade III with other known non-lethal amanitas, including A. ballerina, A. chuformis, A. franzii, A. levistriata, and A. pseudogemmata. Neither amatoxins nor phallotoxins were detected in A. ballerinoides and A. bulbulosa by LC-HRMS, which agrees with their placement in the non-lethal subclade III within A. sect. Phalloideae. Finally, a key to the West African species of Amanita sect. Phalloideae is provided.

Many species of Amanita sect. Phalloideae (Fr.) Quél. cause death of people after consumption around the world. Amanita albolimbata, a new species of A. sect. Phalloideae from Benin, is described here. The taxon represents the first lethal species of A. sect. Phalloideae known from Benin. Morphology and molecular phylogenetic analyses based on five genes (ITS, nrLSU, rpb2, tef1-α, and β-tubulin) revealed that A. albolimbata is a distinct species. The species is characterized by its smooth, white pileus sometimes covered by a patchy volval remnant, a bulbous stipe with a white limbate volva, broadly ellipsoid to ellipsoid, amyloid basidiospores, and abundant inflated cells in the volva. Screening for the most notorious toxins by liquid chromatography–high-resolution mass spectrometry revealed the presence of α-amanitin, β-amanitin, and phallacidin in A. albolimbata.