In Florida (and elsewhere, of course), you’ll find much more than epiphytic plants such as the Resurrection fern growing atop the limbs and branches of our oak trees. One particularly nifty and cool organism you’re likely to find on Florida’s Live oaks and other bark-laden trees is the Christmas lichen, Cryptothecia rubrocincta.
Generally speaking, you can think of a lichen as a kind of fungi, only it’s a fungus that lives in relationship to an algae or a cyanobacterium. Any specific species of lichen is a singular biological system, an “organism,” but it is really a biological system comprised of multiple organisms functioning together as a singular system. People often call lichen species “lichenized fungi.” Beyond that, the biological systematics of lichenized fungi are far beyond my pay grade. Flying caribou make more sense to me.
The Christmas lichen is so named for its bright red wreath-like trim. It’s often quite circular in appearance, though the lichen photographed here were a bit erratic and less spherical than you may find otherwise. Christmas lichen tends to stick out somewhat among the more traditionally-green lichens and the typically-brown hues of oak tree bark. Bright reds make for remarkable figure-ground contrasts on all that vegetative base coloring. When it comes to green and red, every day can be Christmas in Florida (but not so much with the powdery white snow stuff).