CHOIROMYCES VENOSUS (Fr.) Th. Fr.
Svensk bot. Tidskr. 3: 240 (1909)
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Basionym:
Mylitta venosa Fr., in Lindblad, Bidrag. till Bleckings Flora: 248 (1830) et Summa veget. Scand.: 436 (1849)
Synonyms:
Choiromyces meandriformis Vittad., Monogr. Tuberac. (Milano): 51 (1831)
Choiromyces gangliiformis Vittad., Monogr. Tuberac. (Milano): 51 (1831)
Tuber album Sowerby, Col. fig. Engl. Fung. Mushr. (London) 3: pl. 310 (1800), sensu Tulasne et C. Tulasne (1851) non T. album Bull., Herb.France pl. 404 (1789)
Rhizopogon meandriformis (Vittad.) Corda, Icon. fung. (Prague) 6: 68 (1840)
Macroscopic characters:
Ascomata: hypogeous or subhypogeous, subglobose, often irregular in form and lobed, tuberculate, 2-8 (-12) cm in size, smooth, initially whitish, becoming yellowish brown, with reddish spots at maturity
Gleba: firm, solid, whitish at first, becoming cream or pale yellowish, marbled at maturity with sterile, whitish to greyish, meander-like veins (which is the origin of the name “meandriformis”) surrounding the fertile areas.
Odour: strong, distinctive, becoming unpleasant at maturity
Taste: nutty, hazelnut-like
Edibility:
Gastronomic value of Choiromyces meandriformis is considered differently through Europe. Some authors do not recommend their raw consumption nor overripe specimens. In Northern Europe is eaten as a delicacy. However, it is considered toxic (gastrointestinal irritant) in Southern Europe. In Spain are included in Annex D (species that can not be traded commercially) of Spanish Royal Decree 30/2009 of 16 January 2009, laying down the health conditions for mushrooms trade for food.
Habitat
Grow in acid soils with high rainfal, associated with deciduous and coniferous trees, and prefer clayey soils. We have found them in Navarra associated with Quercus robur and in Hungarian under Picea abies. They are often visible above ground, although many specimens complete their development underground
Notes:
Immature specimens of Choiromyces meandriformis could be confused with the prized Alba white truffle, Tuber magnatum, and sometimes are sold fraudulently
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Microscopic characters:
Asci: clavate to saccate, short-stalked, 120-180 (200) x 50-70 µm, 8-spored, not stained in Melzer’s Reagent
Ascospores: 17-20 µm excluding ornament, globose, yellow-brown at maturity, ornamented with tube-like, truncate or tapered spines, 3-5 µm high, 2-3 µm across at the base. Some spores are ornamented with hemispherical warts.
Peridium: pseudoparenchymatous, composed of broad cells and interwoven hyphae
 | Antonio Rodríguez trufamania@gmail.com antonio@trufamania.com |