''Neolentinus ponderosus'', commonly known as the giant sawgill, is a species of

fungus A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from th ...

in the family Gloeophyllaceae. Found in western North America, it was originally described in 1965 as a species of ''

Lentinus ''Lentinus'' is a genus of fungi in the family Polyporaceae. The genus is widely distributed, with many species found in subtropical regions. The genus name ''Lentinus'' is derived from the Latin ''lent'', meaning "pliable", and ''inus'', meani ...

'' by American mycologist Orson K. Miller.

Taxonomy

The fungus was first described as ''Lentinellus montanus'' by Orson K. Miller, based on collections that he had made in

Idaho Idaho ( ) is a state in the Pacific Northwest region of the Western United States. To the north, it shares a small portion of the Canada–United States border with the province of British Columbia. It borders the states of Montana and Wyom ...

. In 1985 it was transferred to ''

Neolentinus ''Neolentinus'' is a genus of wood-decaying agarics with tough (leathery to woody) fruit bodies composed of dimitic tissue, serrated lamella edges, and nonamyloid white binucleate basidiospores among other features. It was segregated from ''L ...

'', a segregate genus created for ''

''-type fungi that cause a brown rot in wood. The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

''ponderosa'' derives from the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

word for "heavy".

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 ...

have convex to flattened

caps Caps are flat headgear. Caps or CAPS may also refer to: Science and technology Computing * CESG Assisted Products Service, provided by the U.K. Government Communications Headquarters * Composite Application Platform Suite, by Java Caps, a Java ...

ranging from in diameter. The caps have small cinnamon-brown scales (squamules) on the surface and a margin that is usually curved inward initially. The narrow

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 ...

have an

adnate Adnate may refer to: * Adnation, in botany, the fusion of two or more whorls of a flower * Adnate, in mycology, a classification of lamellae (gills) * Conjoined twins Conjoined twins – sometimes popularly referred to as Siamese twins – are ...

attachment to the stipe and are closely spaced, with intervening lamellulae (short gills) that extend about two-thirds of the distance to the stipe. The gill edges are serrated (notched like a saw), a feature that inspired the mushroom's common name. Gills are initially whitish before aging to light

buff Buff or BUFF may refer to: People * Buff (surname), a list of people * Buff (nickname), a list of people * Johnny Buff, ring name of American world champion boxer John Lisky (1888–1955) * Buff Bagwell, a ring name of American professional ...

to light orange. The stipe measures long by thick. Its reddish-brown surface is made of small scales that are less dense in the upper half, where it has a more whitish or buff color. Fruit bodies produce a dull white to buff

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 pinkish-tan spore print. A 3.5-centimeter ...

. Microscopically, the

spores In biology, a spore is a unit of sexual 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 plants, algae, f ...

are somewhat spindle-shaped when viewed from the side, and elliptical viewed from the front; they measure 8–10.5 by 3.5–4.4 μm and are

inamyloid In mycology a tissue or feature is said to be amyloid if it has a positive amyloid reaction when subjected to a crude chemical test using iodine as an ingredient of either Melzer's reagent or Lugol's solution, producing a blue to blue-black stain ...

. The

basidia A basidium () is a microscopic sporangium (a spore-producing structure) found on the hymenophore of fruiting bodies of basidiomycete fungi which are also called tertiary mycelium, developed from secondary mycelium. Tertiary mycelium is highly-c ...

(spore-bearing cells) are thin-walled and club-shaped, four-spored, and measure 26–36 by 5–8.8 μm. The

cystidia A cystidium (plural cystidia) is a relatively large cell found on the sporocarp of a basidiomycete (for example, on the surface of a mushroom gill), often between clusters of basidia. Since cystidia have highly varied and distinct shapes that ar ...

on both the faces and edges of the gills are thin-walled,

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 ...

(translucent), narrowly club-shaped, and measure 26–36 by 5–8.8 μm. 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 ...

comprises threadlike

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 ...

e with a diameter of 4.4–8 μm, while the cap flesh is made of interwoven hyphae (both thick- and thin-walled) measuring 2.5–6 μm.

Clamp connection A clamp connection is a hook-like structure formed by growing hyphal cells of certain fungi. It is a characteristic feature of Basidiomycetes fungi. It is created to ensure that each cell, or segment of hypha separated by septa (cross walls), rece ...

s are present in the hyphae. The young mushrooms are

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 ...

, although they tend to become tough when mature. The flesh has a fruit or indistinct odor and a mild taste. They are prized by the

Rarámuri The Rarámuri or Tarahumara is a group of indigenous people of the Americas living in the state of Chihuahua in Mexico. They are renowned for their long-distance running ability. Originally, inhabitants of much of Chihuahua, the Rarámuri r ...

Indians of Mexico.

Habitat and distribution

''Neolentinus ponderosus'' is a

saprophytic Saprotrophic nutrition or lysotrophic nutrition is a process of chemoheterotrophic extracellular digestion involved in the processing of decayed (dead or waste) organic matter. It occurs in saprotrophs, and is most often associated with fungi ( ...

species, and grows on the stumps and logs of conifers, particularly

ponderosa pine ''Pinus ponderosa'', commonly known as the ponderosa pine, bull pine, blackjack pine, western yellow-pine, or filipinus pine is a very large pine tree species of variable habitat native to mountainous regions of western North America. It is the ...

. It causes a brown rot in wood, whereby it breaks down the

hemicellulose A hemicellulose (also known as polyose) is one of a number of heteropolymer, heteropolymers (matrix polysaccharides), such as arabinoxylans, present along with cellulose in almost all embryophyte, terrestrial plant cell walls.Scheller HV, Ulvskov H ...

and cellulose to cause a brown discoloration, and the subsequent cracking of the wood into roughly cubical pieces. Fruit bodies grow singly or in small clusters, and usually prefer open spots with direct sunlight. The range of the fungus is restricted to the

Pacific Northwest The Pacific Northwest (sometimes Cascadia, or simply abbreviated as PNW) is a geographic region in western North America bounded by its coastal waters of the Pacific Ocean to the west and, loosely, by the Rocky Mountains to the east. Though ...

region of western North America. Fruiting occurs in late spring, or later (summer) in mountainous locales.

Similar species

The species resembles ''

Neolentinus lepideus ''Neolentinus lepideus'' is a basidiomycete mushroom of the genus ''Neolentinus'', until recently also widely known as ''Lentinus lepideus''. Common names for it include scaly sawgill, scaly lentinus and train wrecker. Appearance ''Neolentinus l ...

'' and ''

Catathelasma imperiale ''Catathelasma imperiale'' is a species of agaric (gilled mushroom) in the family Biannulariaceae. Basidiocarps (fruit bodies) are stocky, with a double annulus (ring), and a tapering to rooting stipe (stem). The species is ectomycorrhizal wit ...

''.

References

{{Taxonbar, from=Q10597380 Edible fungi Fungi described in 1965 Fungi of North America Gloeophyllales