Truffle Genus: Paradoxa

Paradoxa monospora ascospore scale = 20 µm

Kingdom: Fungi Phylum: Ascomycota Order: Pezizales Family: Tuberaceae

Spore Characters

Surface: An irregular reticulum of thick ridges 1-3 µm tall.
Shape and Size: Ellipsoid to globose, 57-80 x 55-80 µm (excluding ornamentation).
Wall: Single, 2-4 µm thick.
Color in Water: Dark brown.
Melzer's Reaction: Not distinctive.
Comments: The very large, reticulate, single-walled spores with no attachment separate Paradoxa readily from all other known truffle-like fungi. This genus is unusual in producing only one spore per ascus. The only other genus known to do this is the tropical Glaziella.

View photos of Paradoxa spores

Sporocarp Characters

Shape and Size: Subglobose to irregular, 0.4-1 cm in diameter.
Peridium: Smooth but with prominent furrows; brown.
Gleba: Solid, pale in youth, but at maturity black-brown marbled with brown meandering veins.
Odor: Not recorded.

View photos of Paradoxa sporocarps

Name Derivation

Named by Italian mycologist Oreste Mattirolo (1935) from Greek para- (beyond) and -doxon (opinion), in reference to the uniqueness of this genus and the difficulty of relating it to other genera.

Distribution

Known only from a few collections in Italy.
Season: Autumn.
Species known from North Temperate Forests: One, P. monospora, known only from Italy.

Keys and Descriptions

Mattirolo (1935). Montecchi and Sarasini (2000).