''Hydnum'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

fungi A fungus (: fungi , , , or ; or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified as one ...

in the family

Hydnaceae The Hydnaceae are a family of fungi in the order Cantharellales. Originally the family encompassed all species of fungi that produced basidiocarps (fruit bodies) having a hymenium (spore-bearing surface) consisting of slender, downward-hanging ta ...

. They are notable for their unusual

spore In biology, a spore is a unit of sexual reproduction, sexual (in fungi) or asexual reproduction that may be adapted for biological dispersal, dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores fo ...

-bearing structures of teeth rather than

gills A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

. The best known are the

edible An edible item is any item that is safe for humans to eat. "Edible" is differentiated from " eatable" because it does not indicate how an item tastes, only whether it is fit to be eaten. Nonpoisonous items found in nature – such as some mushroo ...

species ''

Hydnum repandum ''Hydnum repandum'', commonly known as the sweet tooth, pig's trotter, wood hedgehog or hedgehog mushroom, is a basidiomycete fungus of the family Hydnaceae. First species description, described by Carl Linnaeus in 1753, it is the type species ...

'' and '' H. rufescens''. There are no known toxic varieties of ''Hydnum.'' Widely regarded as important maintainers of forest ecosystems, the ''Hydnum'' genus is known to have

ectomycorrhiza An ectomycorrhiza (from Greek ἐκτός ', "outside", μύκης ', "fungus", and ῥίζα ', "root"; ectomycorrhizas or ectomycorrhizae, abbreviated EcM) is a form of symbiotic relationship that occurs between a fungal symbiont, or mycobio ...

l relationships with multiple plant families. ''Hydnum'' has many brittle, white teeth from which the spores drop. Some species have teeth which hang from ascending branches, while other species have teeth which project downwards from the undersurfaces of dead wood. Most ''Hydnum'' species are safe to eat, and contain many fatty acids and antioxidants.

Taxonomy and diversity

''Hydnum'' species are found on every continent that is habitable for plant life, with some preferring deep forest regions. Most of the common species, such as ''H. repandum'' and ''H. rufescens'' can be located in Europe, East Asia, and Australia. ''Hydnum repandum'' is a common and edible species. Also called the "hedgehog mushroom", ''H. repandum'' is most often found in Europe, Mexico, and North America. The smooth

cap A cap is a flat headgear, usually with a visor. Caps have crowns that fit very close to the head. They made their first appearance as early as 3200 BC. The origin of the word "cap" comes from the Old French word "chapeau" which means "head co ...

grows as wide as 8 inches across, and the

stem Stem or STEM most commonly refers to: * Plant stem, a structural axis of a vascular plant * Stem group * Science, technology, engineering, and mathematics Stem or STEM can also refer to: Language and writing * Word stem, part of a word respon ...

is off-center and is less than 2 inches long. ''H. repandum'' is often confused in looks for its similar tasting cousin, the Chantrelle mushroom. Medicinally, ''H. repandum'' has shown promising signs in preventing malignant sarcomas in mice. ''Hydnum rufescens'' is another common edible variety of hydnum. Known locally as the terracotta hedgehog mushroom, it can be found in Portugal. It has been found to contain high levels of fatty acids and nutrients essential to the human diet. ''Hydnum minum'' is a new species that was described in 2015. First located in Japan, ''H. minum'' is identifiable by a "whitish basidiomata", or spore-producing structure. ''Hydnum vesterholtii'' has been newly found in calcium rich areas of the Mediterranean, as well as in the Pyrenees and Italy, and is recognized by an ochre tinted spore cap. ''Hydnum ovoideisporum,'' much like ''H. vesterholtii,'' has an orangish colored cap. It is also found in the Iberian-Mediterranean climate and is fond of calcium rich soils.

Species

References

External links

* * {{Authority control Cantharellales Agaricomycetes genera