SafePlants

Cladonia: The Cup Lichen

Cladonia, commonly known as cup lichen or pixie cup lichen, is a fascinating genus of moss-like lichens belonging to the family Cladoniaceae. These lichens are known for their distinctive cup-shaped structures and their ecological importance.

Considerations for Pets

• Some Cladonia species have upright fruiting stalks.

Considerations for Children

• The "pixie cup" name suggests a small, cup-like structure, approximately 1/2 inch high.

Taxonomy and Nomenclature

• Scientific Name: Cladonia
• Common Names: Cup lichen, Pixie cup lichen
• Family: Cladoniaceae

Distribution and Habitat

• Cladonia species are found across the boreal forest and can be observed on logs, at the base of trees, and on various substrates such as moss and Devonian Red Sandstone boulders.
• They thrive in exposed subalpine sites with poor soils.
• Specific locations mentioned include the Olympic Peninsula and the Eagle Creek Trail in the Columbia River area.

Morphological Characteristics and Growth Habits

• Cladonia lichens exhibit a variety of forms, including cup-like structures, podetia (stalks) shaped like miniature golf tees, and upright fruiting stalks.
• The podetia of some species taper towards the base and can be covered with corticate granules.
• Some species, like those in the Cladonia pyxidata group, exhibit thallus lobes.
• The cup-like structures can be fringed or have round-toothed, curled edges.

Ecological Role

• Cladonia lichens serve as a primary food source for reindeer and caribou.

Interactions with Other Organisms

• As lichens, Cladonia represent a symbiotic relationship between algae and fungus.
• Some species, like Cladonia macilenta, may grow within colonies of other lichens, such as Brachythecium frigidum.

Quirky Facts

• The appearance of *Cladonia* has been compared to "Shrek's Ears".