
British Soldier Lichen
I found a bunch of these tiny lichens growing on a rotting stump in a wooded backyard habitat. They were a lovely sight!
Lichens consist of a mutualistic association between a fungus and an alga (or cynaobacterium). The fungus gives the lichen structure, while the algae provides food. For this lichen, the fungus is Cladonia cristatella and the algae is Trebouxia erici. The spores that the lichen uses to reproduce are created in the red tips. They are dispersed by the wind, and go on to create new lichens once the fungi in the spores meets up with the appropriate alga.
Technically, in mutualistic symbiosis, both organisms should benefit - the fungus receives sugars from the photosynthetic activities of the alga, while the alga receives a safe place to live. However, in reality, studies show that this dual organism is actually a controlled parasitism of the alga by the fungus.

"Cladonia cristatella", commonly known as the British soldier lichen, is a fruticose lichen belonging to the family Cladoniaceae. The species was first described scientifically by the American Botanist Edward Tuckerman in 1858.