Hymenochaetales
Encyclopedia
The Hymenochaetales are an order
of fungi in the class
Agaricomycetes
. The order in its current sense is based on molecular research
and not on any unifying morphological
characteristics. According to one 2008 estimate, the Hymenochaetales contain around 600 species
worldwide, mostly corticioid fungi
and poroid fungi, but also including several clavarioid fungi
and agarics. Species of economic importance include wood decay fungi in the genera Phellinus
and Inonotus
sensu lato, some of which may cause losses in forestry. Therapeutic properties are claimed for Inonotus obliquus ("chaga") and Phellinus linteus
, both of which are now commercially marketed.
Hymenochaetaceae
at a higher taxonomic
rank. As originally conceived, species within the Hymenochaetales had several morphological features in common, notably brown or brownish basidiocarps (fruit bodies) that turn black in alkali
, hyphae lacking clamp connections, and the presence (in most species) of characteristic setae (thick-walled, thorn-shaped cystidia, visible under a hand lens).
Subsequent ultrastructure
research showed that the Hymenochaetales had dolipores with imperforate parenthesomes, whereas most Agaricomycetes have dolipores with perforate parenthesomes. Species of the corticioid genera
Hyphodontia
and Schizopora were later found to share this peculiarity, suggesting they might also be related to the Hymenochaetales, though morphologically dissimilar.
and Coltriciella
; another clade includes the corticioid genera Lyomyces and Schizopora (Schizoporaceae
), together with Coltricia and Coltriciella as a subclade; a further clade (Repetobasidiaceae
) includes agaricoid Rickenella
species, the clavarioid Alloclavaria purpurea
, and various corticioid fungi, including the genus Repetobasidium
; the three remaining clades consist of corticioid Hyphodontia species, corticioid Kneifiella species, and poroid Oxyporus
species.
Not all the species currently placed within the Hymenochaetales have dolipores with imperforate parenthosomes, so the order lacks any shared morphological characteristics.
.
and Inonotus
sensu lato are pathogenic, causing losses in forestry plantations. Therapeutic properties are claimed for Inonotus obliquus ("chaga") and Phellinus linteus
, both of which are commercially marketed as alternative medicines.
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...
of fungi in the class
Class (biology)
In biological classification, class is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, order, family, genus, and species, with class fitting between phylum and order...
Agaricomycetes
Agaricomycetes
Agaricomycetes is a class of fungi. The taxon is roughly identical to that defined for the Homobasidiomycetes by Hibbett & Thorn, with the inclusion of Auriculariales and Sebacinales. It includes not only mushrooms but also most species placed in the deprecated taxa Gasteromycetes and...
. The order in its current sense is based on molecular research
Molecular phylogeny
Molecular phylogenetics is the analysis of hereditary molecular differences, mainly in DNA sequences, to gain information on an organism's evolutionary relationships. The result of a molecular phylogenetic analysis is expressed in a phylogenetic tree...
and not on any unifying morphological
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
characteristics. According to one 2008 estimate, the Hymenochaetales contain around 600 species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
worldwide, mostly corticioid fungi
Corticioid fungi
The corticioid fungi are a group of fungi in the Basidiomycota typically having effused, smooth basidiocarps that are formed on the undersides of dead attached or fallen branches. They are sometimes colloquially called crust fungi or patch fungi...
and poroid fungi, but also including several clavarioid fungi
Clavarioid fungi
The clavarioid fungi are a group of fungi in the Basidiomycota typically having erect, simple or branched basidiocarps that are formed on the ground, on decaying vegetation, or on dead wood. They are colloquially called club fungi and coral fungi...
and agarics. Species of economic importance include wood decay fungi in the genera Phellinus
Phellinus
Phellinus is a genus of fungi in the family Hymenochaetaceae. Many species cause white rot. Fruiting bodies, which are found growing on wood, are resupinate, sessile, and perennial. The flesh is tough and woody or cork-like, and brown in color. Clamp connections are absent, and the skeletal hyphae...
and Inonotus
Inonotus
Inonotus is a genus of fungi in the family Hymenochaetaceae. The genus, circumscribed by Petter Karsten in 1879, is estimated to contain about 80 species sensu lato and 30 species sensu stricto ....
sensu lato, some of which may cause losses in forestry. Therapeutic properties are claimed for Inonotus obliquus ("chaga") and Phellinus linteus
Phellinus Linteus
Phellinus linteus is a medicinal mushroom used in Japan, Korea and China. It is shaped like a hoof, has a bitter taste, and in the wild grows on mulberry trees. The stem's color ranges from dark brown to black...
, both of which are now commercially marketed.
History
The order was proposed in 1977 to recognize the familyFamily (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Hymenochaetaceae
Hymenochaetaceae
The Hymenochaetaceae are a family of fungi in the order Hymenochaetales. The family contains several species that are implicated in many diseases of broad-leaved and coniferous trees, causing heart rot, canker and root diseases, and also esca disease of grapevines...
at a higher taxonomic
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
rank. As originally conceived, species within the Hymenochaetales had several morphological features in common, notably brown or brownish basidiocarps (fruit bodies) that turn black in alkali
Alkali
In chemistry, an alkali is a basic, ionic salt of an alkali metal or alkaline earth metal element. Some authors also define an alkali as a base that dissolves in water. A solution of a soluble base has a pH greater than 7. The adjective alkaline is commonly used in English as a synonym for base,...
, hyphae lacking clamp connections, and the presence (in most species) of characteristic setae (thick-walled, thorn-shaped cystidia, visible under a hand lens).
Subsequent ultrastructure
Ultrastructure
Ultrastructure is the detailed structure of a biological specimen, such as a cell, tissue, or organ, that can be observed by electron microscopy...
research showed that the Hymenochaetales had dolipores with imperforate parenthesomes, whereas most Agaricomycetes have dolipores with perforate parenthesomes. Species of the corticioid genera
Genera
Genera is a commercial operating system and development environment for Lisp machines developed by Symbolics. It is essentially a fork of an earlier operating system originating on the MIT AI Lab's Lisp machines which Symbolics had used in common with LMI and Texas Instruments...
Hyphodontia
Hyphodontia
Hyphodontia is a genus of fungi in the family Hymenochaetaceae. The genus was circumscribed by Swedish mycologist John Eriksson in 1958.-Species:*H. bieticola*H. adhaerispora*H. alba*H. alienata*H. aloha*H. altaica...
and Schizopora were later found to share this peculiarity, suggesting they might also be related to the Hymenochaetales, though morphologically dissimilar.
Current status
Molecular research, based on cladistic analysis of DNA sequences, has substantially expanded and redefined the Hymenochaetales, dividing the order into at least six different clades. The core clade represents the traditional Hymenochaetaceae, excluding the genera ColtriciaColtricia
Coltricia is a genus of fungi in the family Hymenochaetaceae.-Species:*Coltricia bambusicola*Coltricia barbata*Coltricia cinnamomea*Coltricia confluens*Coltricia duportii*Coltricia focicola*Coltricia fragilissima...
and Coltriciella
Coltriciella
Coltriciella is a genus of fungi in the family Hymenochaetaceae.-Species list:*Coltriciella corticicola*Coltriciella dependens*Coltriciella navispora*Coltriciella oblectabilis*Coltriciella pusilla*Coltriciella pusilla...
; another clade includes the corticioid genera Lyomyces and Schizopora (Schizoporaceae
Schizoporaceae
Schizoporaceae are a family of fungi in the order Hymenochaetales. These are saprobic, and cause white rots of standing and fallen wood of coniferous and broadleaved trees...
), together with Coltricia and Coltriciella as a subclade; a further clade (Repetobasidiaceae
Repetobasidiaceae
Repetobasidiaceae is a phylogenetically defined family encompassing resupinate, poroid, stereoid, clavaroid, and agaricoid fungi, among other forms. Currently no description of the emended family circumscription is available....
) includes agaricoid Rickenella
Rickenella
Rickenella is a genus of brightly colored bryophilous agarics in the Hymenochaetales that have an omphalinoid morphology. They inhabit mosses on mossy soils, peats, tree trunks and logs in temperate regions of both the Northern and Southern Hemispheres...
species, the clavarioid Alloclavaria purpurea
Alloclavaria purpurea
Alloclavaria purpurea is a coral fungus commonly known as the purple coral, or the purple fairy club. Formerly known as Clavaria purpurea, it has been moved to its own genus as a result of phylogenetic analysis.-Description:...
, and various corticioid fungi, including the genus Repetobasidium
Repetobasidium
Repetobasidium is a genus of fungi in the Hymenochaetales. It was circumscribed by J. Erickson in 1958.-Species:*Repetobasidium americanum*Repetobasidium canadense*Repetobasidium conicum*Repetobasidium erikssonii...
; the three remaining clades consist of corticioid Hyphodontia species, corticioid Kneifiella species, and poroid Oxyporus
Oxyporus
Oxyporus is a genus of fungi in the Schizoporaceae family. A number of species in this genus are plant pathogens. There are 10 species in the genus, which collectively have a widespread distribution....
species.
Not all the species currently placed within the Hymenochaetales have dolipores with imperforate parenthosomes, so the order lacks any shared morphological characteristics.
Habitat and distribution
Most fungi within the order are saprotrophs of dead wood, but some species within the Hymenochaetaceae can cause rots of living trees. Species of Coltricia and Coltriciella are ectomycorrhizal. Agaricoid species of Rickenella and related genera are parasites of mosses and liverworts. Distribution of the Hymenochaetales is cosmopolitanCosmopolitan distribution
In biogeography, a taxon is said to have a cosmopolitan distribution if its range extends across all or most of the world in appropriate habitats. For instance, the killer whale has a cosmopolitan distribution, extending over most of the world's oceans. Other examples include humans, the lichen...
.
Economic importance
Several wood decay fungi in the genera PhellinusPhellinus
Phellinus is a genus of fungi in the family Hymenochaetaceae. Many species cause white rot. Fruiting bodies, which are found growing on wood, are resupinate, sessile, and perennial. The flesh is tough and woody or cork-like, and brown in color. Clamp connections are absent, and the skeletal hyphae...
and Inonotus
Inonotus
Inonotus is a genus of fungi in the family Hymenochaetaceae. The genus, circumscribed by Petter Karsten in 1879, is estimated to contain about 80 species sensu lato and 30 species sensu stricto ....
sensu lato are pathogenic, causing losses in forestry plantations. Therapeutic properties are claimed for Inonotus obliquus ("chaga") and Phellinus linteus
Phellinus Linteus
Phellinus linteus is a medicinal mushroom used in Japan, Korea and China. It is shaped like a hoof, has a bitter taste, and in the wild grows on mulberry trees. The stem's color ranges from dark brown to black...
, both of which are commercially marketed as alternative medicines.