Tuber aestivum Vittadini forma uncinatum (Chatin) Montecchi & Borelli
in Montecchi & Sarasini (2000), Funghi Ipogei d' Europa 255, fig. 256
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Synonyms:
Tuber uncinatum Chatin, C. R. hebdom. Acad. Sciences 104: 1132 (1887); La truffe 55, t. 7 f. 1 a-e
Macroscopic characters:
Ascomata: hypogeous, subglobose, sometimes with a basal cavity, 2–9 cm, blackish-brown to black, conspicuously warted. Warts 3–9 mm across, usually smaller than those of Tuber aestivum, pyramidal, 4–6-sided, vertically fissured, sometimes with transverse striation.
Gleba: firm, solid, white when immature, becoming dark brown at maturity, darker than that of Tuber aestivum, marbled with numerous, thin, white, meandering, branching veins that do not change colour when exposed to the air.
Odour: moderate intensity, stronger than that of Tuber aestivum, distinctive, sometimes phenolic and unpleasant when fully ripe.
Taste: moderate intensity, stronger than that of Tuber aestivum, nutty.
Habitat:
Tuber uncinatum always grows in shaded locations (unlike Tuber aestivum, which typically favours sunny spots). It is the most frequently encountered edible truffle in Europe. The ripening period runs from October through January. Tuber uncinatum is associated with the roots of several trees: oaks (Quercus), beeches (Fagus sylvatica), poplars (Populus), hazels (Corylus), pines (Pinus) and lindens (Tilia).
Notes:
Molecular analysis has shown no differences between Tuber aestivum and Tuber uncinatum. The differences in taste, odour and spore morphology are attributable to ecological factors.
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Microscopic characters:
Asci: globose to subglobose, sessile or short-stalked, 60-90 x 50-80 µm, (1-) 2-6 (-7)-spored (usually 3-4-spored).
Ascospores: 27–45 x 18–27 µm excluding ornament, size variable depending on number of spores in the ascus, Q range = 1.12–1.42, ellipsoid to subglobose, yellow, translucent, ornamented with a coarse irregular reticulum 3–5 (−9) µm high, sometimes bending at the top (presence of hooks in the spore reticulum), meshes variable, usually 3–5 across width of spore and often with incomplete secondary crests inside. These hooks are sometimes also present in Tuber aestivum ascospores; they merely reflect the flexibility of the reticulum walls and are dependent on reticulum height. Meshes are more regular than those of Tuber aestivum ascospores.
Peridium: pseudoparenchymatous
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Antonio Rodríguez trufamania@gmail.com antonio@trufamania.com |