''Royoporus badius'' or ''Picipes badius'', commonly known as the black-footed polypore or black-leg, is a species of

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

in the family

Polyporaceae The Polyporaceae are a family of poroid fungi belonging to the Basidiomycota. The flesh of their fruit bodies varies from soft (as in the case of the dryad's saddle illustrated) to very tough. Most members of this family have their hymeniu ...

. It causes a

white rot A wood-decay or xylophagous fungus is any species of fungus that digests moist wood, causing it to rot. Some species of wood-decay fungi attack dead wood, such as brown rot, and some, such as ''Armillaria'' (honey fungus), are parasitic and col ...

of hardwoods and conifers. The species is found in

temperate In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout ...

areas of Asia, Australia, Europe, and North America. It has a dark brown or reddish-brown

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 ...

that reaches a diameter of , and a stipe that is often completely black or brown at the top and black at the base.

Taxonomy

The species was first described in the scientific literature in 1801 by

Christian Hendrik Persoon Christiaan Hendrik Persoon (1 February 1761 – 16 November 1836) was a German mycologist who made additions to Linnaeus' mushroom taxonomy. Early life Persoon was born in South Africa at the Cape of Good Hope, the third child of an i ...

, who named it ''Boletus badius''. American mycologist

Lewis David de Schweinitz Lewis David de Schweinitz (13 February 1780 – 8 February 1834) was a German-American botanist and mycologist. He is considered by some the "Father of North American Mycology", but also made significant contributions to botany. Education ...

transferred the species to ''

Polyporus ''Polyporus'' is a genus of poroid fungi in the family Polyporaceae. Taxonomy Italian botanist Pier Antonio Micheli introduced the genus in 1729 to include 14 species featuring fruit bodies with centrally-placed stipes, and pores on the under ...

'' in 1832, and it was known by this name until 1997, when De transferred the species into the genus '' Royoporus'', which he had described the year before. Polyporaceae species that are closely phylogenetically related to ''R. badius'' include '' P. dictyopus'', '' P. melanopus'', and '' P. tubaeformis'', which have

clamp connection A clamp connection is a hook-like structure formed by growing hyphal cells of certain fungi. It is a characteristic feature of Basidiomycetes fungi. It is created to ensure that each cell, or segment of hypha separated by septa (cross walls), rec ...

s on generative hyphae and a similar ecology. Zmitrovich & Kovalenko proposed the new genus ''Picipes'' for this fungus together with ''P. melanopus'' and ''P. tubaeformis'' and according to

Species Fungorum ''Index Fungorum'' is an international project to index all formal names (scientific names) in the fungus kingdom. the project is based at the Royal Botanic Gardens, Kew, one of three partners along with Landcare Research and the Institute of M ...

''Picipes badius'' is now the correct current name. The specific epithet ''badius'' derives from the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

root ''badi-'', meaning "reddish brown". The common names "black-footed polypore" and "black-leg" refer to its characteristic dark-colored stipe.

Description

The

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 ...

of ''Royoporus badius'' tend to be upright, growing solitary or in groups, sometimes with two or more fruit bodies arising from a common stipe. The

is circular or kidney-shaped, and often lobed or with a wavy edge. When young, the fruit bodies are convex, then become flat or funnel-shaped in maturity, reaching dimensions of across by thick. The upper cap surface is smooth and glossy, but develops radial wrinkles as it ages. The color of the cap is brown, often darker in the center and lighter-colored at the margins. The under-surface is white or cream-colored, yellowing when old. Pores are round and number 6–8 per mm, with decurrent tubes (running down the length of the stipe). The stipe, attached to the cap either centrally or laterally, is long by thick, velvety and dark brown to blackish-brown, black and longitudinally wrinkled when old. The fruit bodies are inedible because of their tough texture. The

spores In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, ...

are ellipsoid or cylindrical, hyaline (translucent), smooth, and 7.5–9 by 3–5 µm. The

basidia A basidium () is a microscopic sporangium (a spore-producing structure) found on the hymenophore of fruiting bodies of basidiomycete fungi which are also called tertiary mycelium, developed from secondary mycelium. Tertiary mycelium is highly- ...

(spore-bearing cells) are club-shaped with a narrow base, and have dimensions of 20–30 by 7–9 µm. Like other members of the genus ''Polyporus'', this species has a dimitic hyphal construction, meaning that the hyphae are made of both generative hyphae and skeleto-ligative hyphae, a feature which tends to make the mushroom tissue hard and woody. There are no

cystidia A cystidium (plural cystidia) is a relatively large cell found on the sporocarp of a basidiomycete (for example, on the surface of a mushroom gill), often between clusters of basidia. Since cystidia have highly varied and distinct shapes that ar ...

in the hymenium. The fungus has been shown to produce asexual spores when grown in

pure culture A microbiological culture, or microbial culture, is a method of multiplying microbial organisms by letting them reproduce in predetermined culture medium under controlled laboratory conditions. Microbial cultures are foundational and basic diagn ...

conditions.

Habitat and distribution

''Royoporus badius'' is a

saprobic Saprotrophic nutrition or lysotrophic nutrition is a process of chemoheterotrophic extracellular digestion involved in the processing of decayed (dead or waste) organic matter. It occurs in saprotrophs, and is most often associated with fungi ( ...

species, and causes

. It grows on the standing or fallen trunks and branches of various hardwood genera, including '' Acer'', ''

Aesculus The genus ''Aesculus'' ( or ), with species called buckeye and horse chestnut, comprises 13–19 species of flowering plants in the family Sapindaceae. They are trees and shrubs native to the temperate Northern Hemisphere, with six spe ...

'', ''

Alnus Alders are trees comprising the genus ''Alnus'' in the birch family Betulaceae. The genus comprises about 35 species of monoecious trees and shrubs, a few reaching a large size, distributed throughout the north temperate zone with a few sp ...

'', ''

Betula A birch is a thin-leaved deciduous hardwood tree of the genus ''Betula'' (), in the family Betulaceae, which also includes alders, hazels, and hornbeams. It is closely related to the beech- oak family Fagaceae. The genus ''Betula'' contains 30 t ...

'', '' Castanea'', ''

Fagus Beech (''Fagus'') is a genus of deciduous trees in the family Fagaceae, native to temperate Europe, Asia, and North America. Recent classifications recognize 10 to 13 species in two distinct subgenera, ''Engleriana'' and ''Fagus''. The ''Engle ...

'', '' Fraxinus'', '' Populus'', ''

Prunus ''Prunus'' is a genus of trees and shrubs, which includes (among many others) the fruits plums, Cherry, cherries, peaches, Peach#Nectarine, nectarines, apricots, and almonds. Native to the North American temperate regions, the neotropics of Sou ...

'', ''

Robinia ''Robinia'' is a genus of flowering plants in the family Fabaceae, tribe Robinieae, native to North America. Commonly known as locusts, they are deciduous trees and shrubs growing tall. The leaves are pinnate with 7–21 oval leaflets. The flo ...

'', ''

Quercus An oak is a tree or shrub in the genus ''Quercus'' (; Latin "oak tree") of the beech family, Fagaceae. There are approximately 500 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably ...

'', ''

Salix Willows, also called sallows and osiers, from the genus ''Salix'', comprise around 400 speciesMabberley, D.J. 1997. The Plant Book, Cambridge University Press #2: Cambridge. of typically deciduous trees and shrubs, found primarily on moist s ...

'', '' Tilia'' and ''

Ulmus Elms are deciduous and semi-deciduous trees comprising the flowering plant genus ''Ulmus'' in the plant family Ulmaceae. They are distributed over most of the Northern Hemisphere, inhabiting the temperate and tropical-montane regions of Nor ...

''. The fungus grows in

regions of Asia, Europe, and North America.

References

{{Taxonbar, from1=Q327708, from2=Q96636858 Polyporaceae Fungi of Asia Fungi of Australia Fungi of Europe Fungi of North America Fungi described in 1783 Inedible fungi Taxa named by Christiaan Hendrik Persoon