The Hymenochaetales are an
order
Order, ORDER or Orders may refer to:
* Categorization, the process in which ideas and objects are recognized, differentiated, and understood
* Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of ...
of
fungi
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 fr ...
in the
class
Class or The Class may refer to:
Common uses not otherwise categorized
* Class (biology), a taxonomic rank
* Class (knowledge representation), a collection of individuals or objects
* Class (philosophy), an analytical concept used differently ...
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
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriat ...
worldwide,
mostly
corticioid fungi and
poroid fungi, but also including several
clavarioid fungi and
agarics
An agaric () is a type of fungus fruiting body characterized by the presence of a pileus (cap) that is clearly differentiated from the stipe (stalk), with lamellae (gills) on the underside of the pileus. In the UK, agarics are called "mushroom ...
. Species of economic importance include wood decay fungi in the genera ''
Phellinus
''Phellinus'' is a genus of fungi in the family Hymenochaetaceae. Many species cause white rot. Fruit 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. ...
'' and ''
Inonotus'' sensu lato, some of which may cause losses in forestry. Therapeutic properties are claimed for ''
Inonotus obliquus
''Inonotus obliquus'', commonly called chaga (a Latinisation of the Russian word ''чага''), is a fungus in the family Hymenochaetaceae. It is parasitic on birch and other trees. The sterile conk is irregularly formed and resembles burnt ...
'' ("chaga") and ''
Phellinus linteus
''Phellinus linteus'' (Japanese "meshimakobu", Chinese "song gen", Korean "sanghwang", English "mesima", American English "black hoof mushroom") is a mushroom. It is shaped like a hoof, has a bitter taste, and in the wild grows on mulberry trees ...
'', both of which are now commercially marketed.
Taxonomy
History
The order was proposed in 1977 to recognize the
family
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...
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
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 ...
, and the presence (in most species) of characteristic
setae
In biology, setae (singular seta ; from the Latin word for "bristle") are any of a number of different bristle- or hair-like structures on living organisms.
Animal setae
Protostomes
Annelid setae are stiff bristles present on the body. ...
(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.
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
A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English te ...
.
The core clade represents the traditional Hymenochaetaceae, excluding the genera ''
Coltricia
''Coltricia'' is a genus of fungi in the family Hymenochaetaceae. It was circumscribed by Samuel Frederick Gray
Samuel Frederick Gray (10 December 1766 – 12 April 1828) was a British botanist, mycologist, and pharmacologist. He was the fathe ...
'' 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
''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 South ...
'' species,
the clavarioid ''
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
The fruiting ...
'',
and various corticioid fungi, including the genus ''
Repetobasidium''; the three remaining clades consist of corticioid ''Hyphodontia'' species, corticioid ''
Kneifiella'' species, and