Dumontinia tuberosa
What You Should Know
Dumontinia is a fungal genus in the family Sclerotiniaceae. The genus is monotypic, containing the single species Dumontinia tuberosa, found in Europe. This small brown pezize is a phytopathogenic parasite of certain Anemones, mainly the Anemone sylvie, its long foot being attached deeply to a sclerotium, that is to say to an underground heap of hard, black mycelium, forming a sleeve around an old rhizome on which the fungus feeds and constituting a food reserve from which the spring fruiting develops. The species is present throughout the Holarctic ecozone.
Dumontinia tuberosa Mushroom Identification
Fruit Bodies
1-4 cm in diameter and the thickness is up to 3 cm, initially goblet-shaped, with a thick, inwardly curved edge, with a small opening at the top, later cup-shaped, funnel-shaped, with a flat, slightly inwardly curved edge, located on an elongated stem, waxy, develop on sclerotia. The hymenial layer is smooth, slightly wrinkled at the bottom, and brown, located on the inner surface of the cup. The outer surface is sterile, smooth, and light brown.
Stem
The stem is 2-10 cm high, 0.3 cm in diameter, thin, uneven, the base is deeply immersed in the soil, slightly hairy, brownish-brown, blackish.
Sclerotia
1-3 cm long, rounded-elongated, black, white inside, located on the surface or in the tissue of the Anemone rhizome.
Flesh
The flesh is thin, brittle, whitish, and without pronounced smell and taste.
Spores
15-18 * 6-8 μm, elongated-elliptical in shape.
Spore Print
Whitish-yellowish.
Habitat
It grows from April to the end of May, in deciduous and mixed forests, in lowlands, in groups, sclerotia develop on the rhizomes of Anemone.
Dumontinia tuberosa Look-Alikes
Sclerotinia sclerotiorum
Which is a common synonym of Sclerotinia ficariae is morphologically similar to Dumontinia tuberosa. However, its apothecium is golden brown, its spores are 9 to 13 µm long and 4 to 6 µm wide and contain less than four guttules. In addition, it is a saprobiont of a wide range of plants such as the buttercup and cultivated plants such as Phaseolus, Daucus, Helianthus and Solanum into whose tissue the sclerotium is embedded, the latter usually measuring 30 mm by 10 mm. In the case where Dumontinia tuberosa is a parasite of the buttercup, the specimens are difficult to differentiate. Other more tenuous criteria can then be used: the outer layer of the apothecium of Dumontinia tuberosa is composed of hyphae with distended cells generally embedded in a gel and the outer part of the sclerotium is composed of a single layer of cells with hyphae keyed. Conversely, the outer layer of the apothecium of Sclerotinia sclerotiorum is composed of globose cells and the outer part of its sclerotium is composed of two to six layers of globose hyphae.
Sclerotinia trifoliorum
Is a parasite of Fabaceae like the genus Trifolium. Its color tends more towards reddish brown, its size is smaller and its spores measure 13 to 17 µm long and 7 to 9 µm wide. Its black sclerotium is irregularly shaped and can measure up to 20 mm by 10 mm.
Stromatinia rapulum
Is also a species of morphologically similar phytopathogenic fungi but it parasitizes rhizomes of the genus Polygonatum. It's stalked apothecia resemble those of Dumontinia tuberosa and its spores, which measure 10 to 17 µm long and 5 to 8 µm wide, have similar dimensions.
Dumontinia tuberosa Taxonomy and Etymology
This is one of the oldest known pézizes. It was first described by the German botanist Johannes Hedwig in 1788, under the name Octospora tuberosa. But it had been collected and illustrated more than ten years earlier, in 1777, by his compatriot Johann Jacob Reichard (de). The species was recombined in the genus Peziza in 1790 by the Scotsman James Dickson and then formally described in 1791 by the Frenchman Pierre Bulliard, which constitutes its basionym. Throughout the 19th century, its sclerotia, its parasitism on the rhizomes of Anemones and its conidia attracted the attention of renowned mycologists such as the French Edmond Tulasne, Hector Léveillé and Jules de Seynes or the Prussian Anton de Bary.
This species was recombined in 1870 in the genus Sclerotinia, which includes the pezizes producing sclerotia. The American mycologist Linda Myra Kohn created a separate genus in 1979 to bring together the species of Sclerotinia with the particular cellular structure of the excipulum, that is to say, the outer cells of the apothecia with a prismatic texture and the compound inner part detached hyphae in a gelatinous matrix. Sclerotinia ulmariae, which produces a sclerotia on Meadowsweet is also recombined in this genus by Kohn as Dumontinia ulmariae.
The genus name Dumontinia is a tribute to the American mycologist from the New York Botanical Garden Kent Parsons Dumont, a colleague of the author. The specific epithet “tuberosa” refers to the sclerotium, tuber meaning "truffle, domed roo".
In French, the species is called by its popularized and standardized name "Sclérotinie tubereuse". The popularized name Peziza tuberosa was also used in the 18th and 19th centuries.
Dumontinia tuberosa Synonyms
Octospora tuberosa Hedw., 1789
Peziza tuberosa (Hedw.) Dicks., 1790
Peziza tuberosa Bull., 1791
Macroscyphus tuberosus (Hedw.) Gray, 1821
Sclerotinia tuberosa (Hedw.) Fuckel, 1870
Hymenoscyphus tuberosus (Bull.) W. Phillips, 1887
Whetzelinia tuberosa (Hedw.) Korf & Dumont, 1972
Sources:
Photo 1 - Author: Holger Krisp (Creative Commons Attribution 3.0 Unported)
Photo 2 - Author: Lukas from London, England (Creative Commons Attribution-Share Alike 2.0 Generic)
Photo 3 - Author: Krzysztof Ziarnek, Kenraiz (Creative Commons Attribution-Share Alike 4.0 International)
Photo 4 - Author: bjoerns (Creative Commons Attribution-Share Alike 4.0 International)
