''Hydnellum scrobiculatum'', commonly known as the ridged tooth or rough hydnellum, is a

tooth fungus The hydnoid fungi are a group of fungi in the Basidiomycota with basidiocarps (fruit bodies) producing spores on pendant, tooth-like or spine-like projections. They are colloquially called tooth fungi. Originally such fungi were referred to the ...

in the family

Bankeraceae The ''Bankeraceae'' are a family of fungi in the order Thelephorales. Taxa are terrestrial, and ectomycorrhizal with plant species in families such as Pinaceae or Fagaceae. The family was circumscribed by Marinus Anton Donk in 1961. Accordin ...

. Widely distributed in the

Northern Hemisphere The Northern Hemisphere is the half of Earth that is north of the Equator. For other planets in the Solar System, north is defined as being in the same celestial hemisphere relative to the invariable plane of the solar system as Earth's Nort ...

, it is found in Asia, Europe, and North America.

Taxonomy

The fungus was first described as a species of '' Hydnum'' by

Elias Magnus Fries Elias Magnus Fries (15 August 1794 – 8 February 1878) was a Swedish mycologist and botanist. Career Fries was born at Femsjö (Hylte Municipality), Småland, the son of the pastor there. He attended school in Växjö. He acquired ...

in his 1815 work ''Observationes mycologicae''.

Petter Karsten Petter Adolf Karsten (16 February 1834 – 22 March 1917) was a Finnish mycologist, the foremost expert on the fungi of Finland in his day, and known in consequence as the "father of Finnish mycology". Karsten was born in Merimasku near Turku, s ...

transferred it to the genus ''

Hydnellum ''Hydnellum'' is a genus of tooth fungi in the family Bankeraceae (order Thelephorales). Widely distributed in the Northern Hemisphere, the genus contains around 40 species. The fruitbodies of its members grow by slowly enveloping nearby bits o ...

'' in 1879. Canadian mycologist Kenneth A. Harrison published the variety ''H. scrobiculatum'' var. ''zonatum'' as a new combination in 1961, but this is now considered to be

synonymous A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are all ...

with ''

Hydnellum concrescens ''Hydnellum concrescens'' is an inedible fungus, commonly known as the zoned hydnellum or zoned tooth fungus. As with other tooth fungi, the spores are produced on spines on the underside of the cap, rather than gills. It has a funnel-shaped ...

''.

Common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contrast ...

s given to the species include "pitted corky spine fungus", and the British Mycological Society recommended name "ridged tooth".

Description

Fruitbodies of ''Hydnellum scrobiculatum'' have centrally depressed caps measuring in diameter. These caps can fuse together to form concrescent fruitbodies. The caps have wavy edges, and an initially felty surface that becomes scaly with age. Young fruit bodies are white, then pinkish-brown, then purplish brown, sometimes with white margins. Fruitbodies can become shiny in age. The spines on the cap underside are up to 4 mm long. They are initially white, but become purplish brown in maturity. The spines are decurrent—they run down the length of the stipe. The stipe, which is roughly the same color as the cap, measures long by thick. Mycelium at the base of the stipe envelops and grows around forest litter. The flesh smells mealy (similar to freshly ground flour). The edibility of the fruitbody was previously unknown, but Roger Phillips calls it "poor". In general, ''Hydnellum'' species are too acrid and woody to be palatable. Like all ''Hydnellum'' species, ''H. scrobiculatum'' produces a brown spore print. Individual spores have a more or less spherical shape, with dimensions of 5.5–6.5 by 4–5.6

μm The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Unit ...

. They have wart-like projections (tubercles) on the surface. The basidia (spore-bearing cells) are narrowly club-shaped, four-spored, and measure 23–29 by 5–6.5 μm.

Similar species

There are several species that ''Hydnellum scrobiculatum'' is often confused with—especially older specimens. These include '' H. spongiosipes'', '' H. ferrugineum'', and '' H. concrescens''. The latter species is particularly similar to ''H. scrobiculatum'', a fact that has been highlighted by conservation efforts in the UK.

Habitat and distribution

''Hydnellum scrobiculatum'' fruits singly, in clusters, or in fused groups in both

coniferous Conifers are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All extant ...

and mixed forest. It is found in Asia, Europe, and North America. In the United Kingdom, it is considered

vulnerable Vulnerable may refer to: General * Vulnerability * Vulnerability (computing) * Vulnerable adult * Vulnerable species Music Albums * ''Vulnerable'' (Marvin Gaye album), 1997 * ''Vulnerable'' (Tricky album), 2003 * ''Vulnerable'' (The Used album) ...

according to the biodiversity action plan for stiped hydnoid fungi, and endangered according to the

Red Data List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biologi ...

References

External links