Symbioses between plants and nitrogen-fixing cyanobacteria are benchmark biological systems to understand mutualism and patterns of coevolution. The diversity of cyanobacteria associated to non-vascular land plants is still being unraveled, with a huge gap in knowledge from tropical areas, especially in hornworts. Hornworts are arguably the oldest land plant lineage with a widespread symbiosis with cyanobacteria (Villarreal & Renzaglia 2015). We focus on the Neotropical horn...

As part of his undergraduate research project, Philip Bell-Doyon surveyed the Panamanian endemic cycad Zamia pseudoparasitica from May to July 2018 (here a previous paper from his project). The species is the only strictly epiphytic gymnosperm and its life history is little known due to the inaccessibility of the plants. He used single-rope and prussik-knot tree climbing techniques to estimate population density and ant-garden specificity were evaluated. Zamia pseudoparasitica is locally com...

Stigomena is a genus of cyanobacteria that is often the photobiont associated with the lichen genus Stereocaulon. To elucidate the evolutionary relationships between Stereocaulon and Stigonema and assess whether there is specificity or selectivity at the ecosystem or species levels, we performed phylogenetic analyses on specimens collected throughout Eastern Canada. We generated ITS sequences from the fungal component of the symbiosis and sequences from the operon rbcL-rbcX and the trnL ...