35 research outputs found
Ecological Specialization of Two Photobiont- Specific Maritime Cyanolichen Species of the Genus Lichina
22 páginas, 4 tablas, 4 figurasAll fungi in the class Lichinomycetes are lichen-forming and exclusively associate with cyanobacteria.
Two closely related maritime species of the genus Lichina (L. confinis and L.
pygmaea) show similar distribution ranges in the Northeast Atlantic, commonly co-occurring
at the same rocky shores but occupying different littoral zones. By means of 16S rRNA and
phycocyanin operon markers we studied a) the phylogenetic relationships of cyanobionts
associated with these species, b) the match of divergence times between both symbionts,
and c) whether Lichina species differ in photobiont association and in how geography and
ecology affect selectivity. The cyanobionts studied are closely related to both marine and
freshwater strains of the genus Rivularia.We found evidence of a high specificity to particular
cyanobiont lineages in both species: Lichina pygmaea and L. confinis incorporate specific
lineages of Rivularia that do not overlap at the haplotype nor the OTU levels. Dating
divergences of the fungal and cyanobacterial partners revealed an asynchronous origin of
both lineages. Within each fungal species, selectivity varied across the studied area, influenced
by environmental conditions (both atmospheric and marine), although patterns were
highly correlated between both lichen taxa. Ecological speciation due to the differential
association of photobionts to each littoral zone is suspected to have occurred in marine
Lichina.Both ROA (BES-2013-066105) and SPO
(CTM2012-38222-C02-02) were supported in the
form of salary by grants from the Spanish Ministry of
Economy and Competitiveness.Peer reviewe