''Hydnum rufescens'', commonly known as the terracotta hedgehog, is an edible

basidiomycete Basidiomycota () is one of two large divisions that, together with the Ascomycota, constitute the subkingdom Dikarya (often referred to as the "higher fungi") within the kingdom Fungi. Members are known as basidiomycetes. More specifically, Ba ...

of 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 ...

. It belongs to the small group of mushrooms often referred to as the tooth fungi, which produce

fruit bodies The sporocarp (also known as fruiting body, fruit body or fruitbody) 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 cyc ...

whose

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. Caps typically have a visor, or no brim at all. They are popular in casual and informal se ...

undersurfaces are covered by

hymenophore A hymenophore refers to the hymenium-bearing structure of a fungal fruiting body. Hymenophores can be smooth surfaces, lamellae Lamella (plural lamellae) means a small plate or flake in Latin, and in English may refer to: Biology * Lamella (myc ...

s resembling spines or teeth, and not pores or

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 ...

. It is very similar to the commoner hedgehog fungus (''

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

''), and was previously sometimes considered a

variety Variety may refer to: Arts and entertainment Entertainment formats * Variety (radio) * Variety show, in theater and television Films * ''Variety'' (1925 film), a German silent film directed by Ewald Andre Dupont * ''Variety'' (1935 film), ...

of that species. However, the following differences have been noted:Courtecuisse, R. & Duhem, B. (1994) "Guide des champignons de France et d'Europe" Delachaux et Niestlé , also available in English. *the cap of ''H. rufescens'' is russet rather than beige, *the overall dimensions are smaller and more regular in shape, with a central stipe, *the spines are not

decurrent ''Decurrent'' (sometimes decurring) is a term used in botany and mycology to describe plant or fungal parts that extend downward. In botany, the term is most often applied to leaf blades that partly wrap or have wings around the stem or petio ...

, and *the spores are slightly larger. Both species are found in European coniferous and

deciduous In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, ...

forests growing on soil. It is reportedly ectomycorrhizal with ''

Picea abies ''Picea abies'', the Norway spruce or European spruce, is a species of spruce native to Northern, Central and Eastern Europe. It has branchlets that typically hang downwards, and the largest cones of any spruce, 9–17 cm long. It is very close ...

'', ''

Pinus sylvestris ''Pinus sylvestris'', the Scots pine (UK), Scotch pine (US) or Baltic pine, is a species of tree in the pine family Pinaceae that is native to Eurasia. It can readily be identified by its combination of fairly short, blue-green leaves and or ...

'', ''

Fagus sylvatica ''Fagus sylvatica'', the European beech or common beech is a deciduous tree belonging to the beech family Fagaceae. Description ''Fagus sylvatica'' is a large tree, capable of reaching heights of up to tall and trunk diameter, though more ...

'' and ''

Quercus robur ''Quercus robur'', commonly known as common oak, pedunculate oak, European oak or English oak, is a species of flowering plant in the beech and oak family, Fagaceae. It is a large tree, native to most of Europe west of the Caucasus. It is widel ...

''.

References

''Hydnum rufescens''
at Northern Ireland Fungus Group URL accessed 11 June 2007 * Edible fungi Fungi described in 1800 Fungi of Europe Taxa named by Christiaan Hendrik Persoon rufescens {{Agaricomycetes-stub