A truffle is the fruiting body of a subterranean ascomycete fungus, predominantly one of the many species of the genus Tuber. In addition to Tuber, over one hundred other genera of fungi are classified as truffles including Geopora, Peziza, Choiromyces, and Leucangium. These genera belong to the class Pezizomycetes and the Pezizales order. Several truffle-like basidiomycetes are excluded from Pezizales, including Rhizopogon and Glomus. Truffles are ectomycorrhizal fungi, so they are usually found in close association with tree roots. Spore dispersal is accomplished through fungivores, animals that eat fungi. These fungi have significant ecological roles in nutrient cycling and drought tolerance.
The Russulaceae are a diverse family of fungi in the order Russulales, with roughly 1,900 known species and a worldwide distribution. They comprise the brittlegills and the milk-caps, well-known mushroom-forming fungi that include some edible species. These gilled mushrooms are characterised by the brittle flesh of their fruitbodies.
Russula is a very large genus composed of around 750 worldwide species of ectomycorrhizal mushrooms. They are typically common, fairly large, and brightly colored – making them one of the most recognizable genera among mycologists and mushroom collectors. Their distinguishing characteristics include usually brightly coloured caps, a white to dark yellow spore print, brittle, attached gills, an absence of latex, and absence of partial veil or volva tissue on the stem. Microscopically, the genus is characterised by the amyloid ornamented spores and flesh (trama) composed of spherocysts. Members of the related genus Lactarius have similar characteristics but emit a milky latex when their gills are broken. The genus was described by Christian Hendrik Persoon in 1796.
Rhizopogon is a genus of ectomycorrhizal basidiomycetes in the family Rhizopogonaceae. Species form hypogeous sporocarps commonly referred to as "false truffles". The general morphological characters of Rhizopogon sporocarps are a simplex or duplex peridium surrounding a loculate gleba that lacks a columnella. Basidiospores are produced upon basidia that are borne within the fungal hymenium that coats the interior surface of gleba locules. The peridium is often adorned with thick mycelial cords, also known as rhizomorphs, that attach the sporocarp to the surrounding substrate. The scientific name Rhizopogon is Greek for 'root' (Rhiz-) 'beard' (-pogon) and this name was given in reference to the rhizomorphs found on sporocarps of many species.
The sporocarp of fungi is a multicellular structure on which spore-producing structures, such as basidia or asci, are borne. The fruitbody is part of the sexual phase of a fungal life cycle, while the rest of the life cycle is characterized by vegetative mycelial growth and asexual spore production.
The Sclerodermataceae are a family of fungi in the order Boletales, containing several genera of unusual fungi that little resemble boletes. Taxa, which include species commonly known as the ‘hard-skinned puffballs’, ‘earthballs’, or 'earthstars', are widespread in both temperate and tropical regions. The best known members include the earthball Scleroderma citrinum, the dye fungus Pisolithus tinctorius and the 'prettymouths' of the genus Calostoma.
The Hydnangiaceae are a family of fungi in the mushroom order Agaricales. Widespread in temperate and tropical regions throughout the world, the family contains about 30 species in four genera. Species in the Hydnangiaceae form ectomycorrhizal relationships with various species of trees in both coniferous and deciduous forests.
The Albatrellaceae are a family of fungi in the order Russulales. The family contains 9 genera and more than 45 species.
Albatrellus subrubescens is a species of polypore fungus in the family Albatrellaceae. The fruit bodies (mushrooms) of the fungus have whitish to pale buff-colored caps that can reach up to 14.5 cm (5.7 in) in diameter, and stems up to 7 cm (2.8 in) long and 2 cm (0.8 in) thick. On the underside of the caps are tiny light yellow to pale greenish-yellow pores, the site of spore production. When the fruit bodies are fresh, the cap and pores stain yellow where exposed, handled, or bruised.
Rhizopogonaceae are a family of fungi in the order Boletales. The family, first named and described by botanists Ernst Albert Gäumann and Carroll William Dodge in 1928, contains 2 genera and 151 species. The genus Fevansia, formerly thought to belong in the Rhizopogonaceae, was found to belong in the Albatrellaceae in a molecular phylogenetics study.
Astraeus is a genus of fungi in the family Diplocystaceae. The genus, which has a cosmopolitan distribution, contains nine species of earthstar mushroom. They are distinguished by the outer layer of flesh (exoperidium) that at maturity splits open in a star-shape manner to reveal a round spore sac. Additionally, they have a strongly hygroscopic character—the rays will open when moist, but when hot and dry will close to protect the spore sac. Species of Astraeus grow on the ground in ectomycorrhizal associations with trees and shrubs. Despite their similar appearance to the Geastrum earthstars Astraeus is not closely related.
Durianella is a fungal genus in the suborder Boletineae, family Boletaceae of the order Boletales. It contains the single species Durianella echinulata, found in Peninsular Malaysia and Borneo.
Suillus quiescens is a pored mushroom of the genus Suillus in the family Suillaceae. First collected in 2002 on Santa Cruz Island off the coast of California, in association with Bishop Pine, the species was scientifically described and named in 2010. In addition to its distribution in coastal California, it was also found forming ectomycorrhizae with the roots of pine seedlings in the eastern Sierra Nevada, coastal Oregon, and the southern Cascade Mountains. It resembles Suillus brevipes, but can be distinguished from that species by its paler-colored immature cap and by the tiny colored glands on the stipe that darken with age.
Geopora cooperi, commonly known as the pine truffle or the fuzzy truffle, is a species of fungus in the family Pyronemataceae. It has a fuzzy brown outer surface and an inner surface of whitish, convoluted folds of tissue. Widely distributed in the Northern Hemisphere, the species has been recorded from Asia, Europe, and North America.
Tuber oregonense, commonly known as the Oregon white truffle, is a species of edible truffle in the genus Tuber. Described as new to science in 2010, the North American species is found on the western coast of the United States, from northern California to southern British Columbia west of the Cascade Range. A mycorrhizal fungus, it grows in a symbiotic association with Douglas fir. It overlaps in distribution with the closely related T. gibbosum, but they have different growing seasons: T. oregonense typically appears from October through March, while T. gibbosum grows from January to June. The fruit bodies of the fungus are roughly spherical to irregular in shape, and resemble small potatoes up to 5 cm (2 in) in diameter. Inside the truffle is the gleba, which is initially white before it becomes a marbled tan color. The large, often thick-walled, and strongly ornamented spores are produced in large spherical asci. The truffle is highly prized for its taste and aroma. Some individuals have claimed success in cultivating the truffles in Christmas tree farms.
Kalapuya brunnea is a species of truffle in the monotypic fungal genus Kalapuya. The truffle occurs only in the Pacific Northwest region of the United States, in western Oregon and northern California. Known locally as the Oregon brown truffle, it was formerly thought to be an undescribed species of Leucangium until molecular analysis demonstrated that it was distinct from that genus. The truffle is reddish brown with a rough and warty outer skin, while the interior spore-producing gleba is initially whitish before developing greyish-brown mottling as it matures. Mature truffles have an odor resembling garlicky cheese, similar to mature Camembert. The species has been harvested for culinary purposes in Oregon.
Byssoporia is a fungal genus in the family Albatrellaceae. The genus is monotypic, containing the single widespread corticioid species Byssoporia terrestris. There are several varieties: sartoryi, lilacinorosea, aurantiaca, sublutea, and parksii. These differ in bruising reaction, presence of clamp connections in the hyphae, or hyphal morphology. It was previously thought to belong in the Atheliaceae, but a molecular phylogenetics found it to belong in the Albatrellaceae.
James Martin Trappe is a mycologist and expert in the field of North American truffle species. He has authored or co-authored 450 scientific papers and written three books on the subject. MycoBank lists him as either author or co-author of 401 individual species, and over the course of his career he has helped guide research on mycorrhizal fungi, and reshaped truffle taxonomy: establishing a new order, two new families, and 40 individual genera.
Rhizopogon occidentalis is an ectomycorrhizal fungus in the family Rhizopogonaceae of the Basidiomycota. It occurs most commonly in western North America in association with two-needle and three-needle pine hosts. They are false truffles with fruiting bodies that are yellow on the surface and pale yellow inside. Their edibility is disputed.
Carbomyces emergens is a desert truffle in the genus Carbomyces, a small genus common to the Chihuahuan desert in the southwestern United States and Mexico. C. emergens is regarded as the most common and widely distributed species in Carbomyces, also serving as the genus' type species. C. emergens belongs to the Carbomycetaceae family, in the order Pezizales, class Pezizomycetes, division Ascomycota.
