''Agaricus perobscurus'', commonly known as the princess (along with its European relative '' A. lanipes''), is a species of choice edible

basidiomycete Basidiomycota () is one of two large divisions that, together with the Ascomycota, constitute the subkingdom Dikarya (often referred to as the "higher fungi") within the kingdom Fungi. Members are known as basidiomycetes. More specifically, Basid ...

fungus. It is similar to the choice ''A. augustus'' (the prince) and the toxic '' A. praeclaresquamosus''.

Description

The

cap A cap is a flat headgear, usually with a visor. Caps have crowns that fit very close to the head. They made their first appearance as early as 3200 BC. The origin of the word "cap" comes from the Old French word "chapeau" which means "head co ...

is 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

cap cuticle The pileipellis is the uppermost layer of hyphae in the pileus of a fungal fruit body. It covers the trama, the fleshy tissue of the fruit body. The pileipellis is more or less synonymous with the cuticle, but the cuticle generally describes th ...

bruises slowly tawny-brown, and yellows in KOH. The

flesh Flesh is any aggregation of soft tissues of an organism. Various multicellular organisms have soft tissues that may be called "flesh". In mammals, including humans, ''flesh'' encompasses muscles, fats and other loose connective tissues, ...

is white, soft, and can be up to thick. When injured, it can change to a cream color to tawny. The odor is that of

anise Anise (; '), also called aniseed or rarely anix, is a flowering plant in the family Apiaceae native to the eastern Mediterranean region and Southwest Asia. The flavor and aroma of its seeds have similarities with some other spices and herbs, ...

, with a mild taste. The

gills A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

are free, close, and relatively broad. When young, they have a whitish color, though they turn blackish-brownat maturity. The gills can be either five or six-seried. The stipe can be long, and 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

partial veil In mycology, a partial veil (also called an inner veil, to differentiate it from the "outer", or universal veil) is a temporary structure of tissue found on the fruiting bodies of some Basidiomycota, basidiomycete fungus, fungi, typically agarics. ...

is white, membranous, and has small brown floccose scales concentrated near the margin. The

annulus Annulus (or anulus) or annular indicates a ring- or donut-shaped area or structure. It may refer to: Human anatomy * ''Anulus fibrosus disci intervertebralis'', spinal structure * Annulus of Zinn, a.k.a. annular tendon or ''anulus tendineus comm ...

is thin and pendulous on the stipe. The

spores In biology, a spore is a unit of sexual (in fungi) or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plant ...

are 6.5–8.0

μm The micrometre (Commonwealth English as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American English), also commonly known by the non-SI term micron, is a unit of length in the International System ...

by 4.5–5.0 μm, smooth, thick-walled, and

ellipsoid An ellipsoid is a surface that can be obtained from a sphere by deforming it by means of directional Scaling (geometry), scalings, or more generally, of an affine transformation. An ellipsoid is a quadric surface; that is, a Surface (mathemat ...

. They are inequilateral in profile, without a conspicuous hilar appendage. Their

germ pore A germ pore is a small pore in the outer wall of a fungal spore through which the germ tube exits upon germination. It can be wikt:apical, apical or eccentric in its location, and, on light microscopy, may be visualized as a lighter coloured are ...

is not evident, and the

spore print 300px, Making a spore print of the mushroom ''Volvariella volvacea'' shown in composite: (photo lower half) mushroom cap laid on white and dark paper; (photo upper half) cap removed after 24 hours showing warm orange ("tussock") color spore print. ...

is a blackish-brown color.

Similar species

The related '' A. augustus'' (the prince) is widely distributed in North America; by contrast, ''A. perobscurus'' has a darker-brown cap, a patchy fibrillose stipe surface at youth, and a different fruiting season. The toxic '' A. praeclaresquamosus'' can be differentiated by its dark-grey cap, a phenolic (rather than aniselike) odor, and a stipe base which yellows immediately when injured.

Habitat and distribution

''Agaricus perobscurus'' is often solitary or in small groups under

conifer Conifers () are a group of conifer cone, cone-bearing Spermatophyte, seed plants, a subset of gymnosperms. Scientifically, they make up the phylum, division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a sin ...

s and

hardwood Hardwood is wood from Flowering plant, angiosperm trees. These are usually found in broad-leaved temperate and tropical forests. In temperate and boreal ecosystem, boreal latitudes they are mostly deciduous, but in tropics and subtropics mostl ...

s. Primarily found in urban parks with trees like

Monterey Cypress ''Hesperocyparis macrocarpa'' also known as ''Cupressus macrocarpa'', or the Monterey cypress is a coniferous tree, and is one of several species of cypress trees native to California. The Monterey cypress is found naturally only on the Centr ...

Monterey Pine ''Pinus radiata'' (synonym (taxonomy), syn. ''Pinus insignis''), the Monterey pine, insignis pine or radiata pine, is a species of pine native to the Central Coast (California), Central Coast of California and Mexico (on Guadalupe Island and Ced ...

, and

Eucalyptus ''Eucalyptus'' () is a genus of more than 700 species of flowering plants in the family Myrtaceae. Most species of ''Eucalyptus'' are trees, often Mallee (habit), mallees, and a few are shrubs. Along with several other genera in the tribe Eucalyp ...

, they fruit on the West Coast of North America from mid to late winter. It is populous in the

San Francisco Bay Area The San Francisco Bay Area, commonly known as the Bay Area, is a List of regions of California, region of California surrounding and including San Francisco Bay, and anchored by the cities of Oakland, San Francisco, and San Jose, California, S ...

Uses

The species is

edible An edible item is any item that is safe for humans to eat. "Edible" is differentiated from " eatable" because it does not indicate how an item tastes, only whether it is fit to be eaten. Nonpoisonous items found in nature – such as some mushroo ...

and choice.

References

{{Taxonbar, from=Q4691343 perobscurus category:Edible fungi Fungi described in 1985 Fungi of North America Fungus species

Description

Similar species

Habitat and distribution

Uses

See also

References