Diversidad de fotobiontes de líquenes (Sticta) de los bosques tropicales del sur de Ecuador

Abstract

Abstract:Sticta (Schreber) Ach. is one of the most conspicuous genera of foliose macrolichens, however, its diversity in Ecuador has been underestimated. On the other hand, because most of its species establish symbioses with cyanobacteria, it is essential to investigate the patterns of selectivity in the establishment of such symbioses. The objective of this study was to characterize morpho-molecularly the diversity of species of the genus Sticta in tropical forests of the south of Ecuador and to analyze the selectivity patterns of its cyanobionts. The morphological and molecular characteristics of 38 specimens were analyzed, considering the rDNA regions: ITS-5.8S for mycobionts and 16S for cyanobionts. Fifteen species were identified, of which five are new records for Ecuador and three are probably new to science. Phylogenetic analysis correlated with the morphological results and grouped the species into six different clades. As for cyanobacteria, three Nostoc spp. clades were determined, two of them associated with different species and genera of lichens, while the third clade was specific for Sticta species. The genus Nostoc is widely generalist, being associated with a broad spectrum of lichen-forming fungi.