What's going on? by Maarten Trybou

First prize 'plants' of the photo competition "Geowonder 2025"

There are as many as 50 species of cup moss in Belgium and the Netherlands. And they all look very similar. To distinguish them, you have to take into account the colour and shape of the scales on the cups, on the stalks and even on the ground. Because they are lichens, and they cover the ground with a crust. But on top of that, they also form those stalked cups to better spread their spores.

Are those scales large or small, granular or flat? Are the cups narrow or wide, flat or chalice-shaped, granular or scaly? Pff, don't get me started. But then, among some nice, regular specimens, I also saw these distorted cups. My first thought was : 'what's going on here?' Is it a fungal infection? A fungus parasitising the cup moss and forming its spores on it? Because fungi parasitise just about everything, even each other, so wouldn't have surprised me at all.

The relatively large cups were fused, showing all sorts of finger-like protrusions with a brown bulbous knob on the end. It reminded me somewhat of the fingers of a tree frog or a gecko, which also have those little suction cups on their fingers. But it seemed typically something you would expect from a fungus.

But so lichens are themselves fungi, albeit inhabited by an algae. In this case, it was simply a distinct species, forming its fruiting bodies like this, with radiating protrusions. The spore-forming cups of the Branched Pixie-cup Lichen are therefore sometimes described as 'exploded' cups. As far as I am concerned, they look more like frog's hands. But other than that, there nothing going on, except some nice spores!