''Lignosus'' is a
genus of
polypore fungi 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 ...
. The genus was
circumscribed
In geometry, the circumscribed circle or circumcircle of a polygon is a circle that passes through all the vertices of the polygon. The center of this circle is called the circumcenter and its radius is called the circumradius.
Not every polyg ...
in 1920 by mycologists
Curtis Gates Lloyd
Curtis Gates Lloyd (July 17, 1859 – November 11, 1926) was an American mycologist known for both his research on the gasteroid and polypore fungi, as well as his controversial views on naming conventions in taxonomy. He had a herbarium with ab ...
and
Camille Torrend Camille Torrend (1875-1961) was a Portuguese clergyman and mycologist. He was active in France, Portugal, Ireland and Brazil. He was a professor of botany and phytopathology at the Imperial Agricultural School of Bahia.
Torrend described the fungi ...
, with ''
L. sacer'' as the
type species.
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 ''Lignosus'' fungi are
annual. They have a
cap that is coloured white to brown, with a central supporting
stipe. The texture of the cap surface is smooth to very finely
tomentose. Pores on the cap underside range in size from small to large. The stipe originates from a
sclerotium in the ground. The
hypha
A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium.
Structure
A hypha consists of one or ...
l system is trimitic. Generative hyphae have
clamp connections and are
hyaline
A hyaline substance is one with a glassy appearance. The word is derived from el, ὑάλινος, translit=hyálinos, lit=transparent, and el, ὕαλος, translit=hýalos, lit=crystal, glass, label=none.
Histopathology
Hyaline cartilage is ...
. There are binding and skeletal hyphae in the
context, sclerotium and the stipe. The
hymenium
The hymenium is the tissue layer on the hymenophore of a fungal fruiting body where the cells develop into basidia or asci, which produce spores. In some species all of the cells of the hymenium develop into basidia or asci, while in others some ...
lacks
cystidia.
Spores are smooth,
ellipsoid
An ellipsoid is a surface that may be obtained from a sphere by deforming it by means of directional scalings, or more generally, of an affine transformation.
An ellipsoid is a quadric surface; that is, a surface that may be defined as the ...
, hyaline, and
inamyloid.
''Lignosus'' is similar in
morphology to ''
Microporus
''Microporus'' is a genus of fungi in the family Polyporaceae. The genus has a widespread distribution and, according to a 2008 estimate, contains 11 species. The genus name combines the Ancient Greek words ("small") and ("pore").
Species
, In ...
'', but the fungi in this latter genus grow on wood and do not arise from a sclerotium. ''Microporus'' spores are cylindrical to allantoid (sausage-shaped).
Species
The
genome of the species ''
L. rhinocerus'', the
sclerotium of which is used as a
traditional medicine in Southeast Asia, was published in 2014. Its genome is enriched with
genes involved in the
biosynthesis
Biosynthesis is a multi-step, enzyme-catalyzed process where substrates are converted into more complex products in living organisms. In biosynthesis, simple compounds are modified, converted into other compounds, or joined to form macromolecules. ...
of
sesquiterpenoid compounds.
Eight species are known in ''Lignosus'':
*''
L. cameronensis''
Chon S.Tan (2013) – Malaysia
*''
L. dimiticus''
Ryvarden (1975)
*''
L. ekombitii''
Douanla-Meli (2003) –
Cameroon
*''
L. goetzei''
(Henn.) Ryvarden (1972)
*''
L. hainanensis''
B.K.Cui (2011) – Tropical China
*''
L. rhinocerus''
(Cooke) Ryvarden (1972)
*''
L. sacer''
(Afzel. ex Fr.) Torrend (1920)
*''
L. tigris''
Chon S.Tan (2013) – Malaysia
References
{{Taxonbar, from=Q6546722
Polyporaceae
Polyporales genera
Taxa described in 1920