The Christmas Wreath Lichen – Cryptothecia rubrocincta

Did you know that there is a lichen named after Christmas? Here comes Cryptothecia rubrocincta – the Christmas wreath lichen.

Christmas Wreath Lichen
The Christmas Wreath Lichen – Cryptothecia rubrocincta

Cryptothecia rubrocincta, commonly called Christmas wreath lichen, grows on the barks of trees, and rarely on stones. It lives in the southeastern USA, central- and South America. It has also been found in some areas of Africa.

What makes this lichen so spectacularly different to any other lichen is its pattern of red and green colors that give the impression of a Christmas wreath – hence its name. In contrast, most other lichens are of light to dark green or blue-green color, grey, brown or black.

The red pigment of the Christmas wreath lichen is called chiodectonic acid. It protects the lichen against the negative effects of ultraviolet light from the sun. The red color can be extracted from the lichen and used as a red dye.

If you are not quite sure what a lichen is, have a look below.

Lichens – The basics

Lichens, such as the Christmas wreath lichen Cryptothecia rubrocincta, represent a symbiotic community between a fungus and algae or cyanobacteria.

Symbiosis means that two or more organisms live together and each of the partners in the relationship gets an advantage out of it.

In the case of lichen, the algae or cyanobacteria are responsible for producing nutritious sugars through the power of captured sunlight (photosynthesis). The fungus provides additional nutrients. It also serves as a protective mesh for its symbionts. In addition, the fungal mesh retains water needed by the algae and cyanobacteria.

Lichens under a microscope: A symbiosis between a fungal mesh (white) and algae or cyanobacteria (green globes).

Lichens are very robust and usually among the first organisms colonizing hardly habitable rocky areas.

Another interesting fact related to Christmas: Some kinds of lichen are the main food source in winter for reindeer.

So Rudolph likes them as comfort food during wintertimes. However, it is not known, if he also eats Christmas wreath lichens when he comes to South America ;0).

For further information on the Christmas wreath lichen Cryptothecia rubrocincta and some great photographs on the real deal go to

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