Research Interests My research is centered on the biodiversity of mushroom-forming fungi with a primary focus on phylogenetic systematics and evolution, and related interests in fungal biogeography, phylogenomics, ecology and conservation.
In an epoch of anthropogenic extinction, there is a pressing need to document life on earth and understand the evolutionary processes that have generated current patterns of biodiversity. Such knowledge is necessary to understand the history of life, and to address the threats that many species currently face. Fungi are crucial to biogeochemical cycles, ecosystems function and a myriad of aspects of human life from medicine to industry, yet current estimates indicate that we have described less than 2% of fungal species on the planet.
My approach to biodiversity studies merges morphology-based and molecular methods to study the origin, evolution and current status of fungal biodiversity. Molecular approaches have revolutionized our knowledge about the most conspicuous among the fungi, the mushroom-forming species in the Basidiomycota, uncovering cryptic diversity, taxonomic relations, ecological roles and phylogeographic patterns. My graduate and postdoctoral work, as well as my long-term research goals, center on studying all these aspects of biodiversity in two hyper-diverse orders of mushroom-forming fungi, the Agaricales (containing the majority of gilled mushrooms) and Polyporales (bracket fungi, polypores, corticioid fungi and others).
Global Biodiversity and Evolution of the Pluteoid clade (Agaricales, Basidiomycota) Pluteus is a large genus of globally distributed, wood-decay, mushroom-forming fungi. It is characterized morphologically by the combination of pink spore-print, free gills, absence of universal veil and inverse hymenophoral trama. Traditional diversity estimates put the total number of species between 150 and 300 spp., but current molecular work indicates those are likely underestimations of the real number of species. Recent research has revealed a great amount of cryptic, or almost cryptic, diversity in Pluteus, and also a great variety of biogeographic patterns across the Holarctic region, including regional and continental endemics, putatively disjunct or relict taxa and cosmopolitan species
Phylogeny and distribution of the species in the Pluteus salicinus complex (Justo et al. 2014)
North American endemic species of Pluteus section Pluteus (Justo et al. 2014)
Systematics and Evolution of the Order Polyporales (Basidiomycota) As part of the PolyPEET project (http://wordpress.clarku.edu/polypeet/), I have collaborated in research related to the systematics of the order Polyporales. In this project we have revised with molecular data the taxonomy of many charismatic genera such as Trametes or Lentinus. We also have provided broad revisions of the brown-rot polypores (the Antrodia clade) and a phylogenetic and phylogenomic overview of the order. Many genera of Polyporales are still in need of revision, especially the corticioid genera, and much work remains to be done towards a modern, phylogeny-based, family-level classification for the order. The species-level taxonomy of almost every genus is also in need of combined morphological and molecular revisions, as recent research has uncovered great amounts of undescribed biodiversity.
Phylogeny of Trametes and related taxa (Justo & Hibbett 2011)
North American Mycoflora The long-term goal of this project is to produce a modern, comprehensive mycoflora of macrofungi for North America. Revisionary taxonomy, molecular systematics and citizen-scientists participation are key aspects of this project (http://www.northamericanmycoflora.org/) Many North American mushrooms are still waiting to be collected and described, and a good number of the supposedly “common” species are still masquerading under incorrect European names or harbor an extensive amount of cryptic diversity.
Undescribed species of Lepiota, so far collected in Massachusetts, New Hampshire and New York