Geopora sumneriana

Description

Geopora sumneriana is a species of European fungus belonging to the family Pyronemataceae. This mushroom forms a rounded brown, roughly hairy ascocarp underground. This fruit body remains subterranean for most of the year but breaks the surface in the spring to form a cream-colored cup (apothecium) up to 7 cm across and 5 cm tall. This species occurs in small groups and is exclusively found associated with cedar trees.

Geopora sumneriana is poisonous if eaten raw, and also toxic even if cooked. In any case, the flesh is insubstantial and, because of the rarity of these cup fungi, it would be irresponsible to gather them.

Common names: Cedar Cup.

Mushroom Identification

1. Fertile (inner) surface

   Pale cream to light grayish beige on the smooth inner (hymenial or spore-bearing) surface, Cedar Cups develop over several months as underground spheres before breaking through the surface of the soil and splitting open in the form of typically 5 to 8 irregular rays. Up to 5cm tall, the cups are typically 5 to 7cm across when fully open. The specimen shown here is not yet fully mature, and its star-like rays will fold back further to create a broader, shallower cup with a crown-like rim.

2. Infertile (outer) surface and stem

   Varying in color from orange-brown to reddish-brown, the outer surface is infertile and covered in curly brown septate fine hairs up to 2mm in length with rounded ends and covered in numerous clear crystals.

3. Asci

   Hyaline, cylindrical, 330 - 370µm x 16 - 22µm, with eight spores per ascus.

   The septate paraphyses are cylindrical, 3-4µm in diameter with slightly clavate with 5-9µm diameter tips.

4. Spores

   Ellipsoidal-fusiform, smooth, 27-37 x 13-16µm; each usually containing two large oil drops. (The spores are produced on the shiny inner surface of the cup.)

5. Spore Print

   White

Look-Alikes

1. Geopora arenosa and Geopora tenuis

   Much smaller and paler; they appear in dry sandy places, the latter most particularly on dune systems.

2. Sarcoscypha austriaca

   The Scarlet Elf Cup, is bright red and grows on dead twigs and branches in mossy woods and sometimes under damp hedgerows.

History

Originally described by Mordecai Cooke and named Peziza sumneriana, this cup fungus was for many years known as Sepultaria sumneriana, a name given to it in 1895 by George Edward Massee (1850 - 1917), co-founder and first president of the British Mycological Society. Its present accepted name, Geopora sumneriana, dates from a 1976 publication by Spanish mycologist M. de la Torre in Anales del Instituto Botanico A.J. Cavanilles.

Synonyms of Geopora sumneriana include Sepultaria sumneriana (Cooke) Massee, Sepultaria sumneri (Berk.) Boud., and Peziza sumneriana Cooke.

The generic name Geopora means earth cup, appropriate for cup fungi that grow on/in the earth. The specific epithet sumneriana may be honoring American biologist Francis Bertody Sumner (1874 – 1945).

The synonymous generic name Sepultaria means underground tomb, and as the cup fungi in this group develop underground and are usually more than half buried even when the cups have opened.

Photo sources:

Photo 1 - Author: Davide Puddu (CC BY-SA 3.0)

Photo 2 - Author: Lukas from London, England (CC BY-SA 2.0)

Photo 3 - Author: Lukas from London, England (CC BY-SA 2.0)

Photo 4 - Author: Björn S... (CC BY-SA 2.0)

Photo 5 - Author: Lukas from London, England (CC BY-SA 2.0)