2014 FMNH REU: IAN MEDEIROS (sophomore, College of the Atlantic)
Advisor: Dr. Robert Lücking (Adjunct Curator and Collections Manager, Botany, S&E) and Dr. Thorsten Lumbsch (Curator and Associate Director of the Integrative Research Center, S&E)
Symposium Presentation Title: Resolving the Phylogeny of the Wirthiotremateae (Graphidaceae) with Morphological and Molecular data
Symposium Presentation Abstract: The family Graphidaceae (lichenized Ascomycota: Ostropales), including the species formerly classified in the separate family Thelotremataceae, is the most important lichen family in the tropics in terms of both species diversity and biomass. Graphidaceae may also be the most speciose lichen family worldwide, with over two thousand species currently known and hundreds more likely undiscovered and undescribed. There are many interesting ecological and evolutionary questions that can be asked about such a large clade; to comprehensively answer these questions, though, we must first understand the family’s phylogeny and species diversity. Previous research at the Field Museum and elsewhere has shown that many of the traditional genera of thelotremoid Graphidaceae are polyphyletic, and has suggested that a group of 17 species from these genera may form a previously unrecognized clade. To study this group with greater resolution we generated sequences for five gene loci (mtSSU, nuLSU, RPB1, RPB2, and EF1-α) and collected morphological data. Our molecular work demonstrates that this potential clade, now designated as the tribe Wirthiotremateae, is indeed monophyletic. Morphological data suggests the correct phylogenetic placement of several Wirthiotremateae species for which we have no genetic data. The molecular data also shows that our herbarium collections for tribe Wirthiotremateae include between two and three previously undescribed species in the genera Wirthiotrema and Austrotrema. Several taxonomic changes are necessary now that the monophyly of Wirthiotremateae is confirmed, including the resurrection of the genus Asteristion, the expansion of Nadvornikia to include two non-mazaedial species, and the creation of the new genus Austrotrema. New combinations to be made are Asteristion alboolivaceum (=Thelotrema albo-olivaceum), A. cupulare (=T. cupulare), A. leucophthalmum (=T. leucophthalmum), A. platycarpoides (=T. platycarpoides), A. platycarpum (=T. platycarpum), Austrotrema bicinctulum (=T. bicinctulum), Nadvornikia expallescens (=Leucodecton expallescens), and N. peninsulae (=Myriotrema peninsulae). These nomenclatural changes, accompanied by our phylogenetic analysis, a dichotomous key to genera and species in the tribe, descriptions of new species, and discussions of distribution and ecology, will be made in a forthcoming monograph of the Wirthiotremateae. This publication will help facilitate future ecological and evolutionary studies on this and other Graphidaceae lineages.
Original Project Title: ATM meets MET - Assembling a Taxonomic Monograph using Modern Electronic Tools
Original Project Description: Taxonomic monographs provide baseline information for many questions related to environmental and human health issues, such as biodiversity assessment and conservation, as well as ecosystem services and bioprospecting to discover new drugs. Monographs are considered a "dusty" and outdated field of biological sciences, but with the advent of new tools such as DNA sequencing, electronic data dissemination, and social media, have entered a new era which allows for a much broader impact of such revisionary work. Monographs are now more important than ever, considering that a large number of species on earth remain to be discovered and are at the same time at the brink of extinction due to the continuous loss of natural habitats.
Research methods and techniques: REU participants will be working on a specific, small group of the lichen family Graphidaceae (about 10–20 species) to produce a monographic treatment for that group. By doing so, they will be trained and work with a broad array of basic and modern techniques required to assemble a monograph, including nomenclature and revision of type specimens, specimen curation, light microscopy and thin-layer chromatography for chemical analysis, producing and analyzing DNA sequence data, assemble phenotype datasets for automated generation of taxonomic keys and descriptions using DELTA and similar programs, imaging and image editing, and using web tools and social media (KE EMu, Symbiota, EOL, LifeDesks, DiscoverLife, Tree of Life, Zooniverse Microplants, FaceBook) to disseminate their data. The monograph will be published in an international journal with the REU student as lead author.