Peltigera Britannica

Day 109: Any of my regular readers will vouch for the fact that I love lichens. In fact, I refer to them as the "wildflowers of winter" because so many of them come into fruit during the cold months of the year. Peltigera britannica is an example. If you look closely at the photos, you will see that the green surface of its lobes are flecked with tiny black dots. These are its cephalodia, small gall-like propagules which are at this point composed of cyanobacteria. Britannica's cephalodia detach easily when mature, often washing off during rainy periods. They then capture the same green algae (Nostoc) found in the parent lichen, and begin to develop lobes of their own. This lichen may also reproduce through the spores contained in its "painted-fingernail" apothecia (photo, right). Many lichens demonstrate more than one reproductive strategy, insurance for their survival.