Agaricus perobscurus
Encyclopedia
Agaricus perobscurus, commonly
known as the "Princess", is a moderate-sized mushroom
. A relative of Agaricus augustus
, which is known as the "Prince", A. perobscurus can be differentiated in several aspects. While the "Prince" is widely distributed in North America, the "Princess" is found only in the San Francisco Bay Area
. Besides its smaller size, it is distinguished from Agaricus augustus by a darker-brown cap, a patchy fibrillose stem
surface at youth, lacking densely floccose-scaly, and a different fruiting season. Another commonly closely associated Agaricus species, Agaricus praeclaresquamosus, is toxic. It can be differentiated by its dark-grey cap, a phenolic, rather than an anise odor, and a stem base which yellows immediately when injured.
is 8–12.0 cm broad, and becomes deeply convex to flattened. The surface is dry, with a uniformly dark-brown disc. The disc can be either flattened or depressed, and is appressed fibrillose-squamulose. Towards the margin, it begins to diffuse. It is brown over a pallid ground color. Meanwhile, the margin is incurved in youth, then decurved, and eventually turns straight or slightly raised. The cuticle
bruises slowly tawny-brown, and yellows in KOH
. The flesh
is white
, soft, and can be up to 1.5 cm thick. When injured, it can change to a cream
color to tawny
. The odor is that of anise
, with a mild taste.
The gills are free, close, and relatively broad. When young, they have a whitish color, though they turn blackish-brown at maturity
. The gills can be either five or six-seried.
The stipe
can be 6–12 cm long, and 1.5–2.0 cm thick. Often tapered to a bulbous base, it can be stuffed to hollow
at maturity
. The surface of apex is white, and silky-striate. The lower portion is white, with the fibrils forming scattered appressed squamules. In contrast, the base of the stipe discolors slowly a dull orange
-brown
where handled. The flesh changes sporadically from a cream-yellow to tawny-brown when injured or cut. The veil
is white, membranous, and has small brown floccose scales concentrated near the margin. The annulus
is thin and pendulous on the stipe.
The spores
are 6.5–8.0 x 4.5–5.0 µm, smooth, thick-walled, and ellipsoid
. In addition, they are inequilateral in profile, without a conspicuous hilar appendage. Their germ pore is not evident, and the spore print
is a blackish-brown color.
s. Primarily found in urban parks with trees like Monterey Cypress, Monterey Pine
, and Eucalyptus
, they fruit in North America from mid to late winter.
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
known as the "Princess", is a moderate-sized mushroom
Mushroom
A mushroom is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or on its food source. The standard for the name "mushroom" is the cultivated white button mushroom, Agaricus bisporus; hence the word "mushroom" is most often applied to those fungi that...
. A relative of Agaricus augustus
Agaricus augustus
Agaricus augustus, known commonly as the prince, is a basidiomycete fungus of the genus Agaricus.-Taxonomy:According to Heinemann's popular division of Agaricus, A. augustus belongs to section Arvenses. The system proposed by Wasser classifies A. augustus within subgenus Flavoagaricus, section...
, which is known as the "Prince", A. perobscurus can be differentiated in several aspects. While the "Prince" is widely distributed in North America, the "Princess" is found only in the San Francisco Bay Area
San Francisco Bay Area
The San Francisco Bay Area, commonly known as the Bay Area, is a populated region that surrounds the San Francisco and San Pablo estuaries in Northern California. The region encompasses metropolitan areas of San Francisco, Oakland, and San Jose, along with smaller urban and rural areas...
. Besides its smaller size, it is distinguished from Agaricus augustus by a darker-brown cap, a patchy fibrillose 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...
surface at youth, lacking densely floccose-scaly, and a different fruiting season. Another commonly closely associated Agaricus species, Agaricus praeclaresquamosus, is toxic. It can be differentiated by its dark-grey cap, a phenolic, rather than an anise odor, and a stem base which yellows immediately when injured.
Description
The capPileus (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...
is 8–12.0 cm broad, and becomes deeply convex to flattened. The surface is dry, with a uniformly dark-brown disc. The disc can be either flattened or depressed, and is appressed fibrillose-squamulose. Towards the margin, it begins to diffuse. It is brown over a pallid ground color. Meanwhile, the margin is incurved in youth, then decurved, and eventually turns straight or slightly raised. The cuticle
Cuticle
A cuticle , or cuticula, is a term used for any of a variety of tough but flexible, non-mineral outer coverings of an organism, or parts of an organism, that provide protection. Various types of "cuticles" are non-homologous; differing in their origin, structure, function, and chemical composition...
bruises slowly tawny-brown, and yellows in KOH
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...
. The 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
White
White is a color, the perception of which is evoked by light that stimulates all three types of color sensitive cone cells in the human eye in nearly equal amounts and with high brightness compared to the surroundings. A white visual stimulation will be void of hue and grayness.White light can be...
, soft, and can be up to 1.5 cm thick. When injured, it can change to a cream
White
White is a color, the perception of which is evoked by light that stimulates all three types of color sensitive cone cells in the human eye in nearly equal amounts and with high brightness compared to the surroundings. A white visual stimulation will be void of hue and grayness.White light can be...
color to 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...
. The odor is that of anise
Anise
Anise , Pimpinella anisum, also called aniseed, is a flowering plant in the family Apiaceae native to the eastern Mediterranean region and Southwest Asia. Its flavor resembles that of liquorice, fennel, and tarragon.- Biology :...
, with a mild taste.
The gills are free, close, and relatively broad. When young, they have a whitish color, though they turn blackish-brown at maturity
Sexual maturity
Sexual maturity is the age or stage when an organism can reproduce. It is sometimes considered synonymous with adulthood, though the two are distinct...
. The gills can be either five or six-seried.
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...
can be 6–12 cm long, and 1.5–2.0 cm thick. Often tapered to a bulbous base, it can be stuffed to hollow
Hollow
-A noun:*A non-closed body which is not solid or filled. i.e. contains empty space or air.**Hollow Earth theory, the idea that the planet Earth has a hollow interior and possibly an inhabitable inner surface....
at maturity
Sexual maturity
Sexual maturity is the age or stage when an organism can reproduce. It is sometimes considered synonymous with adulthood, though the two are distinct...
. The surface of apex is white, and silky-striate. The lower portion is white, with the fibrils forming scattered appressed squamules. In contrast, the base of the stipe discolors slowly a dull orange
Orange (colour)
The colour orange occurs between red and yellow in the visible spectrum at a wavelength of about 585–620 nm, and has a hue of 30° in HSV colour space. It is numerically halfway between red and yellow in a gamma-compressed RGB colour space, the expression of which is the RGB colour wheel. The...
-brown
Brown
Brown is a color term, denoting a range of composite colors produced by a mixture of orange, red, rose, or yellow with black or gray. The term is from Old English brún, in origin for any dusky or dark shade of color....
where handled. The flesh changes sporadically from a cream-yellow to tawny-brown when injured or cut. The veil
Partial veil
thumb|150px|right|Developmental stages of [[Agaricus campestris]] showing the role and evolution of a partial veilPartial veil is a mycological term used to describe a temporary structure of tissue found on the fruiting bodies of some basidiomycete fungi, typically agarics...
is white, membranous, and has small brown floccose scales concentrated near the margin. The annulus
Annulus (mycology)
An annulus is the ring like structure sometimes found on the stipe of some species of mushrooms. The annulus represents the remaining part of the partial veil, after it has ruptured to expose the gills or other spore-producing surface. An annulus may be thick and membranous, or it may be cobweb-like...
is thin and pendulous on the stipe.
The spores
Basidiospore
A basidiospore is a reproductive spore produced by Basidiomycete fungi. Basidiospores typically each contain one haploid nucleus that is the product of meiosis, and they are produced by specialized fungal cells called basidia. In grills under a cap of one common species in the phylum of...
are 6.5–8.0 x 4.5–5.0 µm, smooth, thick-walled, and ellipsoid
Ellipse
In geometry, an ellipse is a plane curve that results from the intersection of a cone by a plane in a way that produces a closed curve. Circles are special cases of ellipses, obtained when the cutting plane is orthogonal to the cone's axis...
. In addition, they are inequilateral in profile, without a conspicuous hilar appendage. Their germ pore is not evident, and 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 a blackish-brown color.
Habitat
A. perobscurus is often solitary or in small groups under conifers and hardwoodHardwood
Hardwood is wood from angiosperm trees . It may also be used for those trees themselves: these are usually broad-leaved; in temperate and boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen.Hardwood contrasts with softwood...
s. Primarily found in urban parks with trees like Monterey Cypress, Monterey Pine
Monterey Pine
The Monterey Pine, Pinus radiata, family Pinaceae, also known as the Insignis Pine or Radiata Pine is a species of pine native to the Central Coast of California....
, and Eucalyptus
Eucalyptus
Eucalyptus is a diverse genus of flowering trees in the myrtle family, Myrtaceae. Members of the genus dominate the tree flora of Australia...
, they fruit in North America from mid to late winter.