Abstract Detail

Bryology and Lichenology

Leavitt, Steven [1], Westberg, Martin [2], Sohrabi, Mohammad [3], Elix, John [4], ST CLAIR, LARRY L [5], Lumbsch, Thorsten [6].

Biogeography in a common, cosmopolitan lichen-forming fungal component of biological soil crusts, Psora decipiens (Psoraceae, Ascomycota).

Multiple drivers shape the spatial distribution of species, including plate tectonics, climatic transitions, orographic barriers, species’ dispersal capacity, etc. However, biogeographic patterns of lichens commonly do not fit conventional expectations based on studies of animals and plants. For example, a number of lichens are known to occur across impressively broad, intercontinental distributions, including some important components of biological soil crust communities (BSCs). The lichen-forming fungal species Psora decipiens (Hedw.) Hoffm. is found on all continents, except South America and Antarctica. This lichen occurs in BSCs in diverse habitats, ranging from hot, arid deserts to alpine steppe/tundra communities. In order to better understand factors that shape population structure in widespread lichen-forming fungal species, we investigated biogeographic patterns in the cosmopolitan taxon Psora decipiens, along with the closely related taxa Psora crenata (Taylor) Reinke, Jb. wiss. and P. saviczii (Tomin) Follmann & A. Crespo. We sampled worldwide populations of these taxa, generated a multi-locus sequence data set to reconstruct evolutionary relationships, and explored phylogeographic patterns. Our results reveal extensive phylogenetic structure in both P. crenata and P. decipiens. Striking phylogeographic patterns were observed for P. crenata, with populations from distinct geographic regions (e.g., western North America, South Africa, and the Middle East) belonging to well-separated monophyletic lineages. In addition, South African populations of P. crenata were recovered in three well-supported sub-clades. While well-supported phylogenetic substructure was also observed in P. decipiens, nearly all lineages were comprised of specimens collected from intercontinental populations. However, all Australian populations of P. decipiens were recovered within a single well-supported monophyletic clade. The taxon P. saviczii was recovered as a well-supported monophyletic group nested within the core group of P. decipiens. Here we discuss biogeographic patterns and potential factors driving the spatial distribution of lineages within the P. crenata and P. decipiens groups. Given that arid and semiarid areas, the predominant environments for BSCs, occupy approximately one third of the Earth’s total land area, our study has important implications for understanding factors influencing the distribution of lichens in these important communities.

1 - Brigham Young University, Department of Biology & M. L. Bean Life Science Museum, 4143 Life Science Building, Provo, UT, 84602, USA
2 - Swedish Museum of Natural History, Department of Botany,, Stockholm, Sweden
3 - Iranian Research Organization for Science and Technology (IROST), Department of Biotechnology, Tehran, Iran
4 - Australian National University, School of Chemistry, Building 137, Canderra, Australia
5 - Brigham Young University, Biology and M.L. Bean Life Science Museum, 1115 M.L. Bean Life Science Museum, Brigham Young University, Provo, Utah, 84602, USA
6 - The Field Museum, Science & Education, 1400 S. Lake Shore Drive, Chicago, IL, 60605, USA

Keywords:
arid & semi-arid
dispersal
Australia
cryptic species
symbiosis
BSCs.

Presentation Type: Oral Paper
Session: 28, Bryology and Lichenology (ABLS) II
Location: Sundance 1/Omni Hotel
Date: Tuesday, June 27th, 2017
Time: 4:00 PM
Number: 28010
Abstract ID:107
Candidate for Awards:None