Message - 7th IAL Symposium

The 7 th International Association for Lichenology Symposium 2012
(2A-2-O2) Submission ID: IAL0177-00001
MAKING SENSE OF CRYPTIC DIVERSITY, BIOGEOGRAPHY, AND DIVERSIFICATION IN
LICHEN-FORMING FUNGI - A STUDY OF BROWN PARMELIOID LICHENS
(PARMELIACEAE, ASCOMYCOTA)
Leavitt S. 1 , Chatwin W. 2 , Garcia S. 1 , Esslinger T. E. 3 , Lumbsch T. 1
1 Botany, The Field Museum of Natural History, Chicago, Illinois, United States
2 Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States
3 Department of Biological Sciences, North Dakota State University, Fargo, North Dakota, United States
While many lichen-forming fungal lineages have geographically restricted distributions, there is
mounting evidence that transoceanic dispersal is common within some lichen associations. However, cryptic
lineages within morphologically and chemically circumscribed taxa likely confound our understanding of the
role of biogeography and long-distance dispersal in many broadly distributed species. In this study we address
species circumscription and biogeographic patterns in two closely related, and notoriously challenging, parmelioid
lichen genera (Melanelixia and Melanohalea) with broad distributions throughout the northern Hemisphere.
Using DNA sequence data from ca. 650 individuals we address current morphological/chemical species
circumscriptions, identify previously unrecognized lineages, and discuss biogeographical patterns. Although
many clades are largely congruent with traditionally circumscribed taxa, some morphologically indistinguishable
groups (cryptic species) are recovered in multiple, distinct genetic lineages in both Melanelixia and Melanohalea.
Strong nodal support and reciprocal monophyly in independent gene trees suggest long-term reproductive
isolation between most lineages. While many lineages are truly widespread and support the hypothesis of
common transoceanic dispersal, a limited number of clades appear to have much more restricted distributional
ranges. We also estimate net diversification rates between Melanelixia and Melanohalea and calculate the difference
between them. Incorporating Bayesian divergence time estimation, we explore potential explanations
for differences in diversification rates and biogeographic patterns.
(2A-2-O3) Submission ID: IAL0272-00001
MOLECULAR PHYLOGENETICS AND SPECIES DELIMITATION IN MENEGAZZIA
(PARMELIACEAE)
Tronstad I. K. 1 , Myles B. C. 2 , Grube M. 3 , Bjerke J. 4
1 Tromso University Museum, University of Tromso, Tromso, Norway
2 Allan Wilson Centre for Molecular Ecology and Evolution, Palmerston North, New Zealand
3 Institute for Plant Sciences, University of Graz, Graz, Austria
4 Norwegian Institute for Nature Research, Tromso, Norway
The genus Menegazzia has its main distribution in the Southern Hemisphere and is particularly species-rich
in temperate forests in South America and Oceania and in mountainous regions close to equator. More
than 70 species have been described, but species new to science are still being discovered. Recent comparative
studies have also shown some formerly separated species to be conspecific, which has led to revisions of
distribution maps. In this study Menegazzia specimens from South America, Australasia, North America, and
Europe have been collected for molecular analysis to elucidate the phylogeny of this genus based on three loci
(nuITS, nuLSU and mtSSU). The results suggest that the genus comprises a large proportion of endemic species
and that chemistry is an important character for species delimitation. Further results will be presented, and
some implications for species delimitation within the genus will be discussed.
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2A-2-O