Lichens are highly successful obligate mutualistic symbioses between fungi and photosynthetic green algae and cyanobacteria that live within their tissues. Bright orange-colored species of the fungi in the group named Teloschistales are among the most noticeable lichens worldwide. This recently redefined group of fungi includes nearly 2,000 described species that live in wide variety of habitats, including surfaces of man-made substrates. This will be the first global phylogenetic study of these brightly colored organisms. The results of this study will lead to a better understanding of the diversity of these fungi, and will likely result in the description of new families and the re-definition of most genera. This study will also be an experimental test of a novel method of finding genetic markers that can be used to study patterns of evolution in fungi and other organisms. This study will also demonstrate the importance of studying the evolution of genes involved in reproduction in organisms living in symbiotic systems.
In addition to the training of one female postdoctoral researcher and one female Ph.D. student, a workshop will be organized during year three of this proposed project to develop a worldwide consensus among all leading experts on a new system of classification for these fungi. This new classification, which will be co-authored by all workshop participants, will be a long-lasting contribution of this project to fungal biology.
Lichens are highly successful obligate mutualistic ectosymbioses between fungi and either or both green algae and cyanobacteria. The bright orange-colored species of the Teloschistales are among the most noticeable lichens worldwide. This recently redefined monophyletic order includes nearly 1,000 species that are present in a myriad of habitats, including man-made substrates and endangered ecosystems such as the coastal fog deserts of Namib and Atacama, where the Teloschistales dominate. This project has been the first global phylogenetic study of the order Teloschistales and its largest family Teloschistaceae. To accomplish our goals, more than 800 specimens were collected during this project, from Alaska to southern Chile, covering areas in America where the sampling had been very scarce (e.g., Selva Alta and Oxapampa-Yanachaga Chemillen National Park in Peru, coastal oasis in Atacama Desert, Chiloe NP in Chile). Many of these areas turned out to be real hotspots of diversity for Teloschistales. Many potential new species were collected on unusual substrates such as cactuses, soil, or mosses. These collections were subsequently used to study and evaluate the morphological characters that define the extraordinary diversity of the Teloschistales. All specimens were deposited at the Duke University Herbarium. Images were captured and stored in databases that will be available through the project website (www.teloschistales.lutzonilab.net/). The results of this study led to a re-delimitation of the order Teloschistales, the description of new families and subfamilies within this order and to the re-circumscription of most genera within the Teloschistaceae. Through an international consortium of leading experts we are currently establishing a formal classification that everybody (amateurs and researchers) can use. Our phylogenetic analyses revealed that within the Teloschistales, one lineage led to the diversification of the mostly bark-inhabiting crustose families Brigantiaeaceae and Letrouitiaceae, with a circumpacific center of diversity, found mostly in the tropics. The other main lineage led to another bark-inhabiting crustose family, mostly tropical, but with an Australasian center of diversity – the Megalosporaceae – which is sister to the mainly rock-inhabiting, cosmopolitan, and species rich Teloschistaceae. The hypothesis that speciation rates increased at the root of the Teloschistaceae was generally supported. The divergence time of this group seems to be aligned with the diversification of Eudicot flowering plants. These findings are particularly interesting because the root of the Teloschistaceae is assocatied with the evolution of a set of key morphological and ecological traits. For example, it seems that the ancestor of the Teloschistales was growing predominantly on bark and lived in the shade of trees and shrubs. With the origin of the Teloschistaceae, this group of lichens seems to have evolved to become predominantly saxicolous (growing on rocks) and became exposed to direct sunlight. This transition from shade to light, is associated with the origin of anthraquinones in the thallus (these are characteristic secondary compounds providing protection against direct sunlight). This study has also served as an empirical evaluation of the Assembling the Fungal Tree of Life (AFToL2) project, which generated the next generation of molecular markers for the phylogenetic study of fungi. We have also addressed several methodological issues, such as dealing with large inclusive datasets, using a novel (cumulative supermatrix) approach. Many international collaborators have participated in this project. Several undergraduate students from South American countries (Mexico, Chile, Colombia, and Peru) have been involved and are currently performing Masters or PhD studies. A high school student actively participated in this project, through the Precollege Program component of a Howard Hughes Undergraduate Biological Sciences Grant. Two female postdoctoral researchers, one female Ph.D. student, and one female undergraduate student of latino descent (REU) received mentorship and scientific training through this project. The main postdoctoral researcher funded by this grant was successful in obtaining a permanent position as Senior Researcher in Mycology, at Kew Royal Botanic Gardens, London, UK. As part of this NSF funded project we organized a workshop where all world-leading experts working on Teloschistales participated in a discussion to establish the state of the global research efforts on the Teloschistales. One of the main goals of this meeting was to establish an international consensus to draft a stable classification of this prominent group of lichen-forming fungi. For more information about this project see: www.teloschistales.lutzonilab.net/
