Tylopilus tabacinus
Encyclopedia
Tylopilus tabacinus is a species of bolete
fungus in the Boletaceae
family. It is characterized by a tawny
-brown cap
measuring up to 17.5 cm (6.9 in) in diameter, and a reticulated stem
up to 16.5 cm (6.5 in) long by 6 cm (2.4 in) thick. A characteristic microscopic feature is the distinctive crystalline substance encrusted on the hypha
e in the surface of the cap. The species is known from the eastern United States from Florida
north to Rhode Island
, and west to Mississippi
, and from eastern Mexico. It is a mycorrhiza
l species, and associates with oak
and beech
trees. The edibility
of the mushroom is unknown.
in 1896 under the name Boletus tabacinus. Peck collected the type specimens in red clay
on the bank of a roadside ditch in Alabama
. William Alphonso Murrill transferred the species to his then newly described genus Ceriomyces in 1909; this genus has since been subsumed into Boletus. Rolf Singer
moved the species to Tylopilus
in 1944. Although Singer considered B. tabacinus to be the same species as Boletus pisciodorus, this opinion was contested by William Alphonso Murrill, who, after examining the type specimens of both species, considered them to be distinct. Murrill's conclusion was later corroborated by Alexander H. Smith
and Harry D. Thiers
in the 1971 monograph
of boletes. In 1945, Singer defined the varieties amarus and dubius that he collected in Florida
.
of the fruit body initially have a rounded shape, but later become broadly convex and eventually flattened in age; they reach dimensions of 4.5 – wide. The color ranges from yellowish-brown to orangish-brown to tobacco brown. The cap surface is dry with a somewhat velvet-like texture, although in larger specimens the surface is areolate (divided into small areas by cracks). The cap margin is even and wavy.
The tubes on the underside of the cap (comprising the hymenium
) are dark brown to cinnamon-brown. The angular to circular pores are lighter in color than the tubes and number about 1–2 pores per millimeter, while the tubes are up to 1.4 cm (0.551181102362205 in) long. The pore surface is depressed around the stem. The cap flesh
is white, but typically stains purplish-buff or pinkish-buff when cut. The stipe
typically measures 4 – by 2.5 – thick. When young, it is bulbous, but matures to become more or less equal in width throughout. Its color is roughly the same as the cap, although it tends to be slightly darker in the upper portion, where it is reticulate (covered with a net-like patterns of ridges). The odor of the mushroom has been described variously as "not distinctive, fruity, fishy, or pungent", while the taste is indistinct to slightly bitter. The edibility
of the mushroom is unknown. The variety amarus is similar in appearance, but has bitter-tasting flesh, while variety dubius has a lighter colored-cap and less distinctive reticulations on the apex of the stem.
Fruit bodies produce a spore print
ranging in color from pinkish-brown to reddish-brown. The spores measure 10–17 by 3.5–4.5 μm, and are fusoid (somewhat spindle-shaped) to elliptical. Spores have a smooth surface, and a plage
(a depressed area where the spore was once attached to the basidium
via the sterigma
). The spore walls are thin, up to 0.2 μm. They are pale yellow to cream green in a solution of potassium hydroxide
, pale yellow-rust in Melzer's reagent
, and blue in Methyl blue
; without stain, they appear hyaline to pale yellow. The cap cuticle
is an interwoven trichodermium—a cellular arrangement whereby the hypha
e are of roughly equal length and arranged perpendicularly to the surface. The terminal (end) cells of the trichodermium are 6.5–11.5 μm in diameter, and roughly equal in width throughout their length. They are encrusted with a crystalline substance, a feature that is uncommon in the Boletaceae. The hyphae of the tubes are 5.0–13.0 μm in diameter. Clamp connection
s are absent from the hyphae.
The basidia (spore-bearing cells) of T. tabacinus are club-shaped and measure 23.5–37.0 by 8.5–13.0 μm. The pleurocystidia (cystidia found on the inner surface of the tubes) are 45.0–60.0 by 6.5–12.5 μm, lanceolate (lance-shaped) to narrowly fusoid-ventricose (enlarged in the middle and somewhat spindle-shaped). Cheilocystidia (cystidia on the outer edges of the tubes) are absent. The caulocystidia (cystidia on the stem) form the reticulations on the stem; they are usually club-shaped and measure 21.0–40.5 by 6.5–10.5 μm.
s, and fruit bodies are usually found solitarily, scattered, or in groups on sandy soil under oaks or in mixed oak-pine woods from July to September. In the United States, the mushroom is distributed from Florida
north to Rhode Island
, and west to Mississippi
. It has also been collected from a montane cloud forest
of Mexican Beech
(Fagus grandifolia var. mexicana) in the state of Hidalgo, Mexico. The occurrence of the mushroom is "occasional to fairly common". The varieties amarus and dubius are rare, known only from their original collection locations in Gainesville, Florida
.
Bolete
A bolete is a type of fungal fruiting body characterized by the presence of a pileus that is clearly differentiated from the stipe, with a spongy surface of pores on the underside of the pileus...
fungus in the Boletaceae
Boletaceae
Boletaceae are a family of mushrooms, primarily characterized by developing their spores in small pores on the underside of the mushroom, instead of gills, as are found in agarics. Nearly as widely distributed as agarics, they include the Cep or King Bolete , much sought after by mushroom hunters...
family. It is characterized by a tawny
Tawny (color)
Tawny is a yellowish brown color. The word means "tan-colored," from Anglo-Norman tauné "associated with the brownish-yellow of tanned leather," from Old French tané "to tan hides," from Medieval Latin tannare, from tannum "crushed oak bark," used in tanning leather, probably from a Celtic source...
-brown cap
Pileus (mycology)
The pileus is the technical name for the cap, or cap-like part, of a basidiocarp or ascocarp that supports a spore-bearing surface, the hymenium. The hymenium may consist of lamellae, tubes, or teeth, on the underside of the pileus...
measuring up to 17.5 cm (6.9 in) in diameter, and a reticulated stem
Stipe (mycology)
thumb|150px|right|Diagram of a [[basidiomycete]] stipe with an [[annulus |annulus]] and [[volva |volva]]In mycology a stipe refers to the stem or stalk-like feature supporting the cap of a mushroom. Like all tissues of the mushroom other than the hymenium, the stipe is composed of sterile hyphal...
up to 16.5 cm (6.5 in) long by 6 cm (2.4 in) thick. A characteristic microscopic feature is the distinctive crystalline substance encrusted on the hypha
Hypha
A hypha is a long, branching filamentous structure of a fungus, and also of unrelated Actinobacteria. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium; yeasts are unicellular fungi that do not grow as hyphae.-Structure:A hypha consists of one or...
e in the surface of the cap. The species is known from the eastern United States from Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
north to Rhode Island
Rhode Island
The state of Rhode Island and Providence Plantations, more commonly referred to as Rhode Island , is a state in the New England region of the United States. It is the smallest U.S. state by area...
, and west to Mississippi
Mississippi
Mississippi is a U.S. state located in the Southern United States. Jackson is the state capital and largest city. The name of the state derives from the Mississippi River, which flows along its western boundary, whose name comes from the Ojibwe word misi-ziibi...
, and from eastern Mexico. It is a mycorrhiza
Mycorrhiza
A mycorrhiza is a symbiotic association between a fungus and the roots of a vascular plant....
l species, and associates with 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...
and 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:...
trees. The edibility
Edible mushroom
Edible mushrooms are the fleshy and edible fruiting bodies of several species of fungi. Mushrooms belong to the macrofungi, because their fruiting structures are large enough to be seen with the naked eye. They can appear either below ground or above ground where they may be picked by hand...
of the mushroom is unknown.
Taxonomy
The species was first described by American mycologist Charles Horton PeckCharles Horton Peck
Charles Horton Peck, born March 30, 1833 in Sand Lake, New York, died 1917 in Albany, New York, was an American mycologist of the 19th and early 20th centuries...
in 1896 under the name Boletus tabacinus. Peck collected the type specimens in red clay
Ultisols
Ultisols, commonly known as red clay soils, are one of twelve soil orders in the United States Department of Agriculture soil taxonomy. They are defined as mineral soils which contain no calcareous material anywhere within the soil, have less than 10% weatherable minerals in the extreme top layer...
on the bank of a roadside ditch in Alabama
Alabama
Alabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland...
. William Alphonso Murrill transferred the species to his then newly described genus Ceriomyces in 1909; this genus has since been subsumed into Boletus. Rolf Singer
Rolf Singer
Rolf Singer was a German-born mycologist and one of the most important taxonomists of gilled mushrooms in the 20th century....
moved the species to Tylopilus
Tylopilus
Tylopilus is a large genus of around 75 species of mycorrhizal bolete fungi separated from Boletus. Its best known member is the bitter bolete , the only species found in Europe. More species are found in North America, such as the edible species Tylopilus chromapes and T. alboater, and the...
in 1944. Although Singer considered B. tabacinus to be the same species as Boletus pisciodorus, this opinion was contested by William Alphonso Murrill, who, after examining the type specimens of both species, considered them to be distinct. Murrill's conclusion was later corroborated by Alexander H. Smith
Alexander H. Smith
Alexander Hanchett Smith was an American mycologist known for his extensive contributions to the taxonomy and phylogeny of the higher fungi, especially the agarics.-Early life:...
and Harry D. Thiers
Harry D. Thiers
Harry Delbert Thiers, born January 22, 1919 in Fort McKavett, Texas, died August 8, 2000 in Ohio, was an American mycologist who studied and named a great many fungi of native to North America, particularly California. Thiers taught mycology at San Francisco State University for many years, and a...
in the 1971 monograph
Monograph
A monograph is a work of writing upon a single subject, usually by a single author.It is often a scholarly essay or learned treatise, and may be released in the manner of a book or journal article. It is by definition a single document that forms a complete text in itself...
of boletes. In 1945, Singer defined the varieties amarus and dubius that he collected in Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
.
Description
The capsPileus (mycology)
The pileus is the technical name for the cap, or cap-like part, of a basidiocarp or ascocarp that supports a spore-bearing surface, the hymenium. The hymenium may consist of lamellae, tubes, or teeth, on the underside of the pileus...
of the fruit body initially have a rounded shape, but later become broadly convex and eventually flattened in age; they reach dimensions of 4.5 – wide. The color ranges from yellowish-brown to orangish-brown to tobacco brown. The cap surface is dry with a somewhat velvet-like texture, although in larger specimens the surface is areolate (divided into small areas by cracks). The cap margin is even and wavy.
The tubes on the underside of the cap (comprising the hymenium
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 cells develop into sterile cells called cystidia or...
) are dark brown to cinnamon-brown. The angular to circular pores are lighter in color than the tubes and number about 1–2 pores per millimeter, while the tubes are up to 1.4 cm (0.551181102362205 in) long. The pore surface is depressed around the stem. The cap flesh
Trama (mycology)
In mycology trama is a term for the inner, fleshy portion of a mushroom's basidiocarp, or fruit body. It is distinct from the outer layer of tissue, known as the pileipellis or cuticle, and from the spore-bearing tissue layer known as the hymenium....
is white, but typically stains purplish-buff or pinkish-buff when cut. The stipe
Stipe (mycology)
thumb|150px|right|Diagram of a [[basidiomycete]] stipe with an [[annulus |annulus]] and [[volva |volva]]In mycology a stipe refers to the stem or stalk-like feature supporting the cap of a mushroom. Like all tissues of the mushroom other than the hymenium, the stipe is composed of sterile hyphal...
typically measures 4 – by 2.5 – thick. When young, it is bulbous, but matures to become more or less equal in width throughout. Its color is roughly the same as the cap, although it tends to be slightly darker in the upper portion, where it is reticulate (covered with a net-like patterns of ridges). The odor of the mushroom has been described variously as "not distinctive, fruity, fishy, or pungent", while the taste is indistinct to slightly bitter. The edibility
Edible mushroom
Edible mushrooms are the fleshy and edible fruiting bodies of several species of fungi. Mushrooms belong to the macrofungi, because their fruiting structures are large enough to be seen with the naked eye. They can appear either below ground or above ground where they may be picked by hand...
of the mushroom is unknown. The variety amarus is similar in appearance, but has bitter-tasting flesh, while variety dubius has a lighter colored-cap and less distinctive reticulations on the apex of the stem.
Fruit bodies produce a 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...
ranging in color from pinkish-brown to reddish-brown. The spores measure 10–17 by 3.5–4.5 μm, and are fusoid (somewhat spindle-shaped) to elliptical. Spores have a smooth surface, and a plage
Plage (mycology)
A plage is a clear, unornamented area on the basal area of an otherwise ornamented spore. Characteristic of spores from the euagaric genus Galerina.-Images:* - line drawing* - photo...
(a depressed area where the spore was once attached to the basidium
Basidium
thumb|right|500px|Schematic showing a basidiomycete mushroom, gill structure, and spore-bearing basidia on the gill margins.A basidium is a microscopic, spore-producing structure found on the hymenophore of fruiting bodies of basidiomycete fungi. The presence of basidia is one of the main...
via the sterigma
Sterigma
thumb|right|The sterigmata is the slender extension that connects the spore to the basidia .A sterigma is an extension of the basidium consisting of a basal filamentous part and a slender projection with a spore at the tip...
). The spore walls are thin, up to 0.2 μm. They are pale yellow to cream green in a solution of potassium hydroxide
Potassium hydroxide
Potassium hydroxide is an inorganic compound with the formula KOH, commonly called caustic potash.Along with sodium hydroxide , this colorless solid is a prototypical strong base. It has many industrial and niche applications. Most applications exploit its reactivity toward acids and its corrosive...
, pale yellow-rust in Melzer's reagent
Melzer's Reagent
Melzer's reagent is a chemical reagent used by mycologists to assist with the identification of fungi.-Composition:...
, and blue in Methyl blue
Methyl blue
Methyl blue, also known as Cotton blue, Helvetia blue, Acid blue 93, or C.I. 42780, is a chemical compound with the molecular formula C37H27N3Na2O9S3. It is used as a stain in histology. Methyl blue stains collagen blue in tissue sections. It is soluble in water and slightly soluble in ethanol...
; without stain, they appear hyaline to pale yellow. The cap cuticle
Pileipellis
thumb|300px||right|The cuticle of some mushrooms, such as [[Russula mustelina]] shown here, can be peeled from the cap, and may be useful as an identification feature....
is an interwoven trichodermium—a cellular arrangement whereby the hypha
Hypha
A hypha is a long, branching filamentous structure of a fungus, and also of unrelated Actinobacteria. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium; yeasts are unicellular fungi that do not grow as hyphae.-Structure:A hypha consists of one or...
e are of roughly equal length and arranged perpendicularly to the surface. The terminal (end) cells of the trichodermium are 6.5–11.5 μm in diameter, and roughly equal in width throughout their length. They are encrusted with a crystalline substance, a feature that is uncommon in the Boletaceae. The hyphae of the tubes are 5.0–13.0 μm in diameter. Clamp connection
Clamp connection
A clamp connection is a structure formed by growing hyphal cells of certain fungi. It is created to ensure each septum, or segment of hypha separated by crossed walls, receives a set of differing nuclei, which are obtained through mating of hyphae of differing sexual types...
s are absent from the hyphae.
The basidia (spore-bearing cells) of T. tabacinus are club-shaped and measure 23.5–37.0 by 8.5–13.0 μm. The pleurocystidia (cystidia found on the inner surface of the tubes) are 45.0–60.0 by 6.5–12.5 μm, lanceolate (lance-shaped) to narrowly fusoid-ventricose (enlarged in the middle and somewhat spindle-shaped). Cheilocystidia (cystidia on the outer edges of the tubes) are absent. The caulocystidia (cystidia on the stem) form the reticulations on the stem; they are usually club-shaped and measure 21.0–40.5 by 6.5–10.5 μm.
Similar species
Boletus pisciodorus is similar in form to Tylopilus tabacinus. Unlike, T. tabacinus however, B. pisciodorus has spores that are hyaline in mass, and dark yellowish-brown rather than hyaline when viewed with a light microscope. Further, B. pisciodorus has a fishy odor that is apparent in both fresh and dried specimens.Habitat and distribution
Tylopilus tabacinus forms ectomycorrhizal associations with oakOak
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...
s, and fruit bodies are usually found solitarily, scattered, or in groups on sandy soil under oaks or in mixed oak-pine woods from July to September. In the United States, the mushroom is distributed from Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
north to Rhode Island
Rhode Island
The state of Rhode Island and Providence Plantations, more commonly referred to as Rhode Island , is a state in the New England region of the United States. It is the smallest U.S. state by area...
, and west to Mississippi
Mississippi
Mississippi is a U.S. state located in the Southern United States. Jackson is the state capital and largest city. The name of the state derives from the Mississippi River, which flows along its western boundary, whose name comes from the Ojibwe word misi-ziibi...
. It has also been collected from a montane cloud forest
Cloud forest
A cloud forest, also called a fog forest, is a generally tropical or subtropical evergreen montane moist forest characterized by a persistent, frequent or seasonal low-level cloud cover, usually at the canopy level. Cloud forests often exhibit an abundance of mosses covering the ground and...
of Mexican Beech
Mexican Beech
Fagus mexicana, the Mexican Beech or Haya, is a species of beech endemic to northeastern and central Mexico, where it occurs from southwest Tamaulipas south to Hidalgo and Puebla...
(Fagus grandifolia var. mexicana) in the state of Hidalgo, Mexico. The occurrence of the mushroom is "occasional to fairly common". The varieties amarus and dubius are rare, known only from their original collection locations in Gainesville, Florida
Gainesville, Florida
Gainesville is the largest city in, and the county seat of, Alachua County, Florida, United States as well as the principal city of the Gainesville, Florida Metropolitan Statistical Area . The preliminary 2010 Census population count for Gainesville is 124,354. Gainesville is home to the sixth...
.