Heliocybe is an agaric

Agaric

An agaric is a type of fungal fruiting body characterized by the presence of a pileus that is clearly differentiated from the stipe , with lamellae on the underside of the pileus. "Agaric" can also refer to a basidiomycete species characterized by an agaric-type fruiting body...

 genus closely allied to Neolentinus and the bracket fungus

Bracket fungus

Bracket fungi, or shelf fungi, among many groups of the fungi in the phylum Basidiomycota. Characteristically, they produce shelf- or bracket-shaped fruiting bodies called conks that lie in a close planar grouping of separate or interconnected horizontal rows...

, Gloeophyllum

Gloeophyllum

The genus Gloeophyllum is characterized by the production of leathery to corky tough, brown, shaggy-topped, revivable fruitbodies lacking a stipe and with a lamellate to daedaleoid or poroid fertile hymenial surfaces. The hyphal system is dimitic to trimitic. The genus is further characterized by...

, all of which cause brown rot of wood. Heliocybe sulcata, the type

Biological type

In biology, a type is one particular specimen of an organism to which the scientific name of that organism is formally attached...

 and sole species, is characterized by thumb-sized, tough, revivable, often dried, mushroom

Mushroom

A mushroom is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or on its food source. The standard for the name "mushroom" is the cultivated white button mushroom, Agaricus bisporus; hence the word "mushroom" is most often applied to those fungi that...

 fruitbodies, with a tanned symmetric pileus

Pileus (mycology)

The pileus is the technical name for the cap, or cap-like part, of a basidiocarp or ascocarp that supports a spore-bearing surface, the hymenium. The hymenium may consist of lamellae, tubes, or teeth, on the underside of the pileus...

 that is radially cracked into a cartoon sun-like pattern of arranged scales and ridges, distant serrated lamellae, and a scaly central stipe

Stipe (mycology)

thumb|150px|right|Diagram of a [[basidiomycete]] stipe with an [[annulus |annulus]] and [[volva |volva]]In mycology a stipe refers to the stem or stalk-like feature supporting the cap of a mushroom. Like all tissues of the mushroom other than the hymenium, the stipe is composed of sterile hyphal...

. Microscopically it differs from Neolentinus by the absence of clamp connection

Clamp connection

A clamp connection is a structure formed by growing hyphal cells of certain fungi. It is created to ensure each septum, or segment of hypha separated by crossed walls, receives a set of differing nuclei, which are obtained through mating of hyphae of differing sexual types...

s. Like Neolentinus, it produces abundant, conspicuous pleurocystidia. Heliocybe sulcata typically fruits on decorticated, sun-dried and cracked wood, such as fence posts and rails, vineyard

Vineyard

A vineyard is a plantation of grape-bearing vines, grown mainly for winemaking, but also raisins, table grapes and non-alcoholic grape juice...

 trellises

Trellis (agriculture)

A trellis is an architectural structure, usually made from interwoven pieces of wood, bamboo or metal that is often made to support climbing plants...

 in Europe, branches in slash

Slash (logging)

Slash, or slashings, is a forestry term that refers to coarse and fine woody debris generated during logging operations or through wind, snow or other natural forest disturbances. Slash generated during logging operations may increase fire hazard and some North American states have passed laws...

 areas, and semi-arid areas such on sagebrush

Sagebrush

Sagebrush is a common name of a number of shrubby plant species in the genus Artemisia native to western North America;Or, the sagebrush steppe ecoregion, having one or more kinds of sagebrush, bunchgrasses and others;...

 or on naio

Myoporum

Myoporum is a genus of flowering plants in the figwort family, Scrophulariaceae . There are about 32 species within the genus, which is spread from Mauritius, across Australia to the Pacific Islands and up to China....

 branches in rain shadow

Rain shadow

A rain shadow is a dry area on the lee side of a mountainous area. The mountains block the passage of rain-producing weather systems, casting a "shadow" of dryness behind them. As shown by the diagram to the right, the warm moist air is "pulled" by the prevailing winds over a mountain...

 areas of Hawaii

Hawaii

Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...

, or in open pine

Pine

Pines are trees in the genus Pinus ,in the family Pinaceae. They make up the monotypic subfamily Pinoideae. There are about 115 species of pine, although different authorities accept between 105 and 125 species.-Etymology:...

 forests.

Etymology

Heliocybe derives from the Greek

Greek language

Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...

 helios

Helios

Helios was the personification of the Sun in Greek mythology. Homer often calls him simply Titan or Hyperion, while Hesiod and the Homeric Hymn separate him as a son of the Titans Hyperion and Theia or Euryphaessa and brother of the goddesses Selene, the moon, and Eos, the dawn...

(= the sun) and cybe (=head), and means "the sun-head". It was coined in reference to its sun-like pattern on its pileus together with its affinity to sun-baked habitats.

Classification

In older classifications, H. sulcatahttp://www.minnesotamushrooms.org/news/2004-02/mush-science.htm was known as Lentinus sulcatus or Panus fulvidus. However, there is strong phylogenetic evidence for the segregation of a group of brown rot causing fungi at the level of order

Order (biology)

In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...

, including Neolentinus and Heliocybe and Gloeophyllum, from the Polyporales

Polyporales

The Polyporales are an order of fungi in the class Agaricomycetes. The order includes some polypores as well as many corticioid fungi and a few agarics . Species within the order are saprotrophic, most of them wood-rotters...

 where Lentinus

Lentinus

Lentinus is a genus of fungi in the family Polyporaceae. There are 40 species in the genus, which have a widespread distribution, especially in subtropical regions....

and Panus

Panus

Panus is a genus of fungi in the family Polyporaceae.-External links:*...

are classified. Heliocybe has also been placed into synonymy with Neolentinus, but anatomically they differ by the absence versus the presence of clamp connections and phylogenetically Heliocybe is distinct, being either a sister group to Neolentinus or to a Neolentinus-Gloeophyllum-clade, or allied to Gloeophyllum odoratum.