Lichenomphalia Umbellifera

Day 169: Lichenomphalia umbellifera fruits largely on decaying wood, inclining the casual lichenophile to dismiss it as an LBM ("little brown mushroom"), and although its finely grained, thin thallus is frequently concealed beneath mosses or other lichens as in the photo on the left, its dark pea-green colour is a clue to this species' true identity (immediately behind the fungus in the righthand image). It is one of very few lichens which exhibits a "mushroom" when it is in fruit, i.e., it is a basidiomycete as opposed to an ascomycete.

"There she goes again," you say, "using those big words. They scare me." Okay, let's break this down. Both fungi and lichens produce spores in specialized structures. Fungal spores are contained in basidia (singular, basidium). On the other hand, most lichen spores come from a similar structure known as an ascus (plural, asci). In the case of Lichenomphalia umbellifera, it reproduces like a fungus, but in its greater aspect, it has all the earmarks of being a lichen.

The fungal body emerges as a warm tan umbrella-shaped cap on a slender stipe. These age to white quite quickly, and turn up at the edges, the better to disperse the spores. They are fairly common in the Pacific Northwest.