Mealy Pixie Cup

Conservation Status

IUCN Red List

not listed

NatureServe

NNR - Unranked
SNR - Unranked

Minnesota

not listed

Description

Mealy Pixie Cup is a common, cosmopolitan lichen. It occurs worldwide on every continent except Antarctica. In the United States it is common in the east and in the west, but it is mostly absent from the deep south, the desert southwest, the Great Plains, and the Great Basin. It grows under full sun or partial shade, on humus and mineral soil, on rotten wood, and on tree trunks.

Mealy Pixie Cup produces two types of vegetative growth (thallus). The primary thallus consists of numerous leaf-like scales (squamules) that often form a dense, carpet-like mat on the substrate. The squamules are ⅛″ to ¼″ (3 to 6 mm) long and 1⁄16″ to ⅛″ (2 to 4 mm) wide, and they are ascending or raised at the margins.The margins have irregular, rounded lobes or teeth. The upper side is grayish green and the underside is white, but the color darkens toward the base. The squamules are persistent, remaining as the secondary thallus matures.

The secondary thallus is a vertical, unbranched, stout or more or less slender stalk (podetium) rising from the primary thallus. It is grayish green to brownish-green and 1⁄16″ to ⅝″ (2 to 15 mm) tall, and does not darken or turn black at the base (non-melanotic). At the tip of the stalk there is a 1⁄16″ to ¼″ (2 to 6 mm) wide cup that gradually tapers to the stalk. The cup is undivided and the margin is unlobed, though it may appear lobed when fruiting structures are present. The layer of protective tissue (cortex) is typically absent or is present just at the very base. As the lichen develops, the cortex breaks up and gives rise to fine, asexual reproductive structures (soredia). These soredia are mealy in texture and cover the outer surface and the interior of the cup.

Egg-shaped to top-shaped (turbinate) reproductive, flask-like structures (pycnidia) are very common on the margin. Disk-shaped, 1⁄16″ to ⅛″ (2 to 4 mm) in diameter, brown, reproductive structures (apothecia) rising from the margin are uncommon.

Mealy Pixie Cup contains fumarprotocetraric acid, which causes a red reaction during standard lichen spot testing (the P+ red test).

Similar Species

Pebbled Pixie Cup (Cladonia pyxidata) is covered in coarser, pebble-like or scale-like granules. However, identification is not always definitive. Juvenile specimens that haven't fully developed soredia, or very old (senescent) specimens where the surface has eroded, can look identical. Because these two species exist on a morphological gradient, some lichenologists argue they should be treated as a single variable species. Both species are often found growing right next to each other.

Trumpet Lichen (Cladonia fimbriata) soredia are significantly finer, resembling a coating of white flour. The cups are typically taller, narrower, and more “trumpet-shaped.”

Ecology

Substrate

Ground

Growth Form

Fruticose

Habitat

Hosts

Distribution

Sources

7, 24, 30, 77, 83.

Biodiversity occurrence data published by: Minnesota Biodiversity Atlas (accessed through the Minnesota Biodiversity Atlas Portal, bellatlas.umn.edu. Accessed 3/7/2026).

The Consortium of North American Lichen Herbaria (CNALH) https://lichenportal.org/cnalh/index.php. Accessed 3/7/2026.

Mycology Collections Portal (MyCoPortal) https://www.mycoportal.org/portal/collections/index.php). Accessed 3/7/2026.

Cladonia chlorophaea (Flörke ex Sommerf.) Spreng. in GBIF Secretariat (2023). GBIF Backbone Taxonomy. Checklist dataset https://doi.org/10.15468/39omei accessed via GBIF.org. Accessed 3/7/2026.

Fink, B. (1910). The Lichens of Minnesota. United States: U.S. Government Printing Office.