On this winter trip (27 May 2019) to Mt Pleasant, the life form that most caught our attention were the lichens covering the rocks. We also found a few animals and a fair number of plants – but for a change, we will start with the lichens…

Lichens

Lichens are actually two, or more, organisms living in a close relationship. One partner is a fungi (the mycobiont) and the other partner (the photobiont) is usually a green algae or sometimes a cyanobacterium. And occasionally there are two photobiont species. This was the description until recently, when it was found that many lichens have a 2nd fungal species involved, which is a yeast. For more about that, see here.

The fungus partner provides minerals, water and shelter; the algae or cyanobacterium photosynthesises, and thereby provides carbohydrates to both partners. Usually the partnership is considered to benefit both, although this is also under review.

You can download an introductory guide to NZ lichens here, and a key to the leafy lichens of NZ here.

(N.B. The photos below often contain more than the one lichen named.)