Low genetic differentiation between apotheciate Usnea florida and sorediate Usnea subfloridana (Parmeliaceae, Ascomycota) based on microsatellite data. Issue 10 (October 2020)

• Record Type: Journal Article
• Authors: Degtjarenko, Polina; Mark, Kristiina; Moisejevs, Rolands; Himelbrant, Dmitry; Stepanchikova, Irina; Tsurykau, Andrei; Randlane, Tiina; Scheidegger, Christoph
• Is Part Of: Fungal biology. Volume 124:Issue 10(2020)
• Page Start: 892
• Page End: 902
• Publication Date: 2020-10
• Subjects: Species pair -- Lichens -- Lichenized fungi -- Species boundaries -- Conservation, Speciation process; Mycology -- Periodicals; Fungi -- Periodicals; 579.505
• DOI: 10.1016/j.funbio.2020.07.007
• Languages: English
• ISSNs: 1878-6146

Abstract

Abstract: Accurate species delimitation has a pivotal role in conservation biology, and it is especially important for threatened species where decisions have political and economic consequences. Finding and applying appropriate character sets and analytical tools to resolve interspecific relationships remains challenging in lichenized fungi. The main aim of our study was to re-assess the species boundaries between Usnea subfloridana and Usnea florida, which have been phylogenetically indistinguishable until now, but are different in reproductive mode and ecological preferences, using fungal-specific simple sequence repeats (SSR), i.e. microsatellite markers. Bayesian clustering analysis, discriminant analysis of principal components (DAPC), minimal spanning network (MSN), and principal component analysis (PCA) failed to separate U. florida and U. subfloridana populations. However, a low significant differentiation between the two taxa was observed across all populations according to AMOVA results. Also, analysis of shared haplotypes and statistical difference in clonal diversity (M) supported the present-day isolation between the apotheciate U. florida and predominantly sorediate U. subfloridana . Our results do not provide a clear support either for the separation of species in this pair or the synonymization of U. florida and U. subfloridana . We suggest that genome-wide data could help resolve the taxonomic question in this species pair. Highlights: Species boundaries between Usnea florida and Usnea subfloridana were re-assessed. Microsatellite markers were used for species delimitation purposes. A high level of gene flow must have occurred between Usnea populations. Our study does not support either for separation or synonymization of study taxa.