Singular cephalodium

Cephalodia are special lichen structures that could be mistaken for an unusual looking apothecia. They only occur on a few select Colorado lichen.

Biologically cephalodia an indicator that the lichen species is a rather exceptional instance of symbiosis. Any lichen with cephalodia is tripartite, containing at least two different photobionts. Generally inside the cephalodia are cyanobacteria and within the lichens cortex are green algae. This is an example of three different kingdoms of life forming one organism.

Cephalodia are generally raised irregularly shaped formations often differencing in color from the lichens thallus. Luckily they generally occur in genera without apothecia. I generally learn that a lichen has cephalodia after identifying it not while identifying it.

The bright green in the photo above is from the community of green algae living within the lichen. The black pebble-like structures are the cephalodia, which would look neon blue under a dissecting microscope.