Exidia glandulosa
Encyclopedia
Exidia glandulosa is a jelly fungus in the family Auriculariaceae
. It is a common, wood-rotting
species in Europe, typically growing on dead attached branches of oak
. The fruit bodies
are up to 3 cm (1.2 in) wide, shiny, black and blister-like, and grow singly or in clusters. Its occurrence elsewhere is uncertain because of confusion with the related species, Exidia nigricans
.
in 1789. It was subsequently placed in Exidia by Fries
in 1822. Fries, however, modified Bulliard's species concept to include a second, effused, coalescing species—the name Exidia glandulosa serving for both. This combined concept was used until Neuhoff separated the two species in 1936. Unfortunately, Neuhoff gave the name Exidia glandulosa to the effused species, adopting the name Exidia truncata for Bulliard's original species. This error was pointed out by Donk in 1966, who proposed the name Exidia plana for the effused species, now replaced by Exidia nigricans
.
Molecular research has shown that Exidia glandulosa and E. nigricans, though similar, are distinct.
The fungus is commonly known as "black witch's butter", "black jelly roll", or the "warty jelly fungus".
that are top-shaped (like an inverted cone) and around 3 cm (1.2 in) across. They are firm when fresh, but become lax and distorted with age or in wet weather. The fruit bodies occur singly or in small clusters. The upper, spore-bearing surface is shiny and dotted with small pimples or pegs. The undersurface is smooth and matte at first, but develops a dense covering of small, gelatinous spines. The fruit bodies are attached to the wood at the base. The spore print
is white. When the fruit bodies are dried they can shrink to form a flattened black crust.
. The basidia are ellipsoid, septate, 15–25 by 8–13 µm
. The spores are allantoid (sausage-shaped), with dimensions of 14–19 by 4.5–5.5 µm.
Exidia glandulosa is frequently confused with Exidia nigricans. The two are similar, but E. nigricans produces button-shaped fruit bodies in clusters that quickly become deformed and coalesce, forming an effused, lobed mass that can be 10 cm (3.9 in) or more across. The two species are indistinguishable microscopically, but DNA research indicates they are distinct. The closely related E. recisa
has more erect fruit bodies without warts on the surface, lighter colors (ranging from yellowish brown to dark brown), and a small base.
The ascomycete Bulgaria inquinans
forms similar, rubbery-gelatinous, blackish fruit bodies on oak. Their upper surfaces are entirely smooth, however, and they produce copious black (not white) spore prints, often leaving a black stain if wiped with the hand.
species, typically found on dead attached branches of broadleaf trees, especially oak, occasionally hazel
or beech
. It is a pioneer species
capable of colonizing living or recently dead wood. A study of the wood decay process in attached oak branches showed that E. glandulosa is a member of a community of eight basidiomycetous fungi consistently associated with the decay of dying branches on living trees. Specifically, its role is to disintegrate the tissue of the vascular cambium
, which loosens the attached bark
. It persists for some while on fallen branches and logs. Fruit bodies are normally produced in the autumn and winter. Its global distribution is uncertain because of confusion with E. nigricans, but it is present in Europe at least.
Auriculariaceae
The Auriculariaceae are a family of fungi in the order Auriculariales. Species within the family were formerly referred to the "heterobasidiomycetes" or "jelly fungi", since many have gelatinous basidiocarps that produce spores on septate basidia. Around 100 species are known worldwide. All are...
. It is a common, wood-rotting
Wood-decay fungus
A wood-decay fungus is a variety of fungus that digests moist wood, causing it to rot. Some wood-decay fungi attack dead wood, such as brown rot, and some, such as Armillaria , are parasitic and colonize living trees. Fungi that not only grow on wood but actually cause it to decay, are called...
species in Europe, typically growing on dead attached branches of oak
Oak
An oak is a tree or shrub in the genus Quercus , of which about 600 species exist. "Oak" may also appear in the names of species in related genera, notably Lithocarpus...
. The fruit bodies
Basidiocarp
In fungi, a basidiocarp, basidiome or basidioma , is the sporocarp of a basidiomycete, the multicellular structure on which the spore-producing hymenium is borne. Basidiocarps are characteristic of the hymenomycetes; rusts and smuts do not produce such structures...
are up to 3 cm (1.2 in) wide, shiny, black and blister-like, and grow singly or in clusters. Its occurrence elsewhere is uncertain because of confusion with the related species, Exidia nigricans
Exidia nigricans
Exidia nigricans is a jelly fungus in the family Auriculariaceae. It is a common, wood-rotting species throughout the northern hemisphere, typically growing on dead attached branches of broadleaf trees...
.
Taxonomy
The species was originally described from France as Tremella glandulosa by BulliardJean Baptiste François Pierre Bulliard
Jean Baptiste François Pierre Bulliard was a French physician and botanist....
in 1789. It was subsequently placed in Exidia by Fries
Elias Magnus Fries
-External links:*, Authors of fungal names, Mushroom, the Journal of Wild Mushrooming.*...
in 1822. Fries, however, modified Bulliard's species concept to include a second, effused, coalescing species—the name Exidia glandulosa serving for both. This combined concept was used until Neuhoff separated the two species in 1936. Unfortunately, Neuhoff gave the name Exidia glandulosa to the effused species, adopting the name Exidia truncata for Bulliard's original species. This error was pointed out by Donk in 1966, who proposed the name Exidia plana for the effused species, now replaced by Exidia nigricans
Exidia nigricans
Exidia nigricans is a jelly fungus in the family Auriculariaceae. It is a common, wood-rotting species throughout the northern hemisphere, typically growing on dead attached branches of broadleaf trees...
.
Molecular research has shown that Exidia glandulosa and E. nigricans, though similar, are distinct.
The fungus is commonly known as "black witch's butter", "black jelly roll", or the "warty jelly fungus".
Description
Exidia glandulosa forms dark sepia to blackish, rubbery-gelatinous fruit bodiesBasidiocarp
In fungi, a basidiocarp, basidiome or basidioma , is the sporocarp of a basidiomycete, the multicellular structure on which the spore-producing hymenium is borne. Basidiocarps are characteristic of the hymenomycetes; rusts and smuts do not produce such structures...
that are top-shaped (like an inverted cone) and around 3 cm (1.2 in) across. They are firm when fresh, but become lax and distorted with age or in wet weather. The fruit bodies occur singly or in small clusters. The upper, spore-bearing surface is shiny and dotted with small pimples or pegs. The undersurface is smooth and matte at first, but develops a dense covering of small, gelatinous spines. The fruit bodies are attached to the wood at the base. The spore print
Spore print
thumb|300px|right|Making a spore print of the mushroom Volvariella volvacea shown in composite: mushroom cap laid on white and dark paper; cap removed after 24 hours showing pinkish-tan spore print...
is white. When the fruit bodies are dried they can shrink to form a flattened black crust.
Microscopic characters
The microscopic characters are typical of the genus ExidiaExidia
Exidia is a genus of fungi in the family Auriculariaceae. Species are saprotrophic, growing on dead attached or recently fallen wood, and produce gelatinous basidiocarps . The fruit bodies are variously pustular, lobed, button-shaped, or top-shaped...
. The basidia are ellipsoid, septate, 15–25 by 8–13 µm
Micrometre
A micrometer , is by definition 1×10-6 of a meter .In plain English, it means one-millionth of a meter . Its unit symbol in the International System of Units is μm...
. The spores are allantoid (sausage-shaped), with dimensions of 14–19 by 4.5–5.5 µm.
Similar species
Exidia recisa
Exidia recisa is a jelly fungus in the family Auriculariaceae. It is a common, wood-rotting species throughout the northern hemisphere, typically growing on dead attached twigs and branches of willow, more rarely other broadleaf trees.-Taxonomy:The species was originally found growing on willow in...
has more erect fruit bodies without warts on the surface, lighter colors (ranging from yellowish brown to dark brown), and a small base.
The ascomycete Bulgaria inquinans
Bulgaria inquinans
Bulgaria inquinans is a fungus from the family Bulgariaceae. It is commonly known by the name Black Bulgar.It grows on branches and bark of dead Oak and Hornbeam. The species can be found from October to March. It can be commonly found on felled trees stored in timber yards...
forms similar, rubbery-gelatinous, blackish fruit bodies on oak. Their upper surfaces are entirely smooth, however, and they produce copious black (not white) spore prints, often leaving a black stain if wiped with the hand.
Habitat and distribution
Exidia glandulosa is a wood-rottingWood-decay fungus
A wood-decay fungus is a variety of fungus that digests moist wood, causing it to rot. Some wood-decay fungi attack dead wood, such as brown rot, and some, such as Armillaria , are parasitic and colonize living trees. Fungi that not only grow on wood but actually cause it to decay, are called...
species, typically found on dead attached branches of broadleaf trees, especially oak, occasionally hazel
Hazel
The hazels are a genus of deciduous trees and large shrubs native to the temperate northern hemisphere. The genus is usually placed in the birch family Betulaceae, though some botanists split the hazels into a separate family Corylaceae.They have simple, rounded leaves with double-serrate margins...
or beech
Beech
Beech is a genus of ten species of deciduous trees in the family Fagaceae, native to temperate Europe, Asia and North America.-Habit:...
. It is a pioneer species
Pioneer species
Pioneer species are species which colonize previously uncolonized land, usually leading to ecological succession. They are the first organisms to start the chain of events leading to a livable biosphere or ecosystem...
capable of colonizing living or recently dead wood. A study of the wood decay process in attached oak branches showed that E. glandulosa is a member of a community of eight basidiomycetous fungi consistently associated with the decay of dying branches on living trees. Specifically, its role is to disintegrate the tissue of the vascular cambium
Vascular cambium
The vascular cambium is a part of the morphology of plants. It consists of cells that are partly specialized, for the tissues that transport water solutions, but have not reached any of the final forms that occur in their branch of the specialization graph...
, which loosens the attached bark
Bark
Bark is the outermost layers of stems and roots of woody plants. Plants with bark include trees, woody vines and shrubs. Bark refers to all the tissues outside of the vascular cambium and is a nontechnical term. It overlays the wood and consists of the inner bark and the outer bark. The inner...
. It persists for some while on fallen branches and logs. Fruit bodies are normally produced in the autumn and winter. Its global distribution is uncertain because of confusion with E. nigricans, but it is present in Europe at least.
External links
- MushroomObserver Images