Hymenium

Last updated

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 (basidiomycetes) or paraphyses (ascomycetes). Cystidia are often important for microscopic identification. The subhymenium consists of the supportive hyphae from which the cells of the hymenium grow, beneath which is the hymenophoral trama , the hyphae that make up the mass of the hymenophore.

Contents

The position of the hymenium is traditionally the first characteristic used in the classification and identification of mushrooms. Below are some examples of the diverse types which exist among the macroscopic Basidiomycota and Ascomycota.

Related Research Articles

<span class="mw-page-title-main">Mushroom</span> Spore-bearing fruiting body of a fungus

A mushroom or toadstool is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground, on soil, or on its food source. Toadstool generally denotes one poisonous to humans.

<span class="mw-page-title-main">Basidiomycota</span> Division of fungi

Basidiomycota is one of two large divisions that, together with the Ascomycota, constitute the subkingdom Dikarya within the kingdom Fungi. Members are known as basidiomycetes. More specifically, Basidiomycota includes these groups: agarics, puffballs, stinkhorns, bracket fungi, other polypores, jelly fungi, boletes, chanterelles, earth stars, smuts, bunts, rusts, mirror yeasts, and Cryptococcus, the human pathogenic yeast. Basidiomycota are filamentous fungi composed of hyphae and reproduce sexually via the formation of specialized club-shaped end cells called basidia that normally bear external meiospores. These specialized spores are called basidiospores. However, some Basidiomycota are obligate asexual reproducers. Basidiomycota that reproduce asexually can typically be recognized as members of this division by gross similarity to others, by the formation of a distinctive anatomical feature, cell wall components, and definitively by phylogenetic molecular analysis of DNA sequence data.

<span class="mw-page-title-main">Hypha</span> Long, filamentous structure in fungi and Actinobacteria

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.

<span class="mw-page-title-main">Basidium</span> Fungal structure

A basidium is a microscopic spore-producing structure found on the hymenophore of reproductive bodies of basidiomycete fungi. These bodies also called tertiary mycelia, which are highly coiled versions of secondary mycelia. The presence of basidia is one of the main characteristic features of the genus. A basidium usually bears four sexual spores called basidiospores. Occasionally the number may be two or even eight. Each reproductive spore is produced at the tip of a narrow prong or horn called a sterigma, and is forcefully expelled at full growth.

An ascocarp, or ascoma, is the fruiting body (sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded asci, each of which typically contains four to eight ascospores. Ascocarps are most commonly bowl-shaped (apothecia) but may take on a spherical or flask-like form that has a pore opening to release spores (perithecia) or no opening (cleistothecia).

<span class="mw-page-title-main">Basidiocarp</span> Fungal structure

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. As with other sporocarps, epigeous (above-ground) basidiocarps that are visible to the naked eye are commonly referred to as mushrooms, while hypogeous (underground) basidiocarps are usually called false truffles.

<span class="mw-page-title-main">Lamella (mycology)</span> Gills used by mushrooms as a means of spore dispersal

In mycology, a lamella, or gill, is a papery hymenophore rib under the cap of some mushroom species, most often agarics. The gills are used by the mushrooms as a means of spore dispersal, and are important for species identification. The attachment of the gills to the stem is classified based on the shape of the gills when viewed from the side, while color, crowding and the shape of individual gills can also be important features. Additionally, gills can have distinctive microscopic or macroscopic features. For instance, Lactarius species typically seep latex from their gills.

<span class="mw-page-title-main">Basidiospore</span> Reproductive structure of a fungus

A basidiospore is a reproductive spore produced by Basidiomycete fungi, a grouping that includes mushrooms, shelf fungi, rusts, and smuts. Basidiospores typically each contain one haploid nucleus that is the product of meiosis, and they are produced by specialized fungal cells called basidia. Typically, four basidiospores develop on appendages from each basidium, of which two are of one strain and the other two of its opposite strain. In gills under a cap of one common species, there exist millions of basidia. Some gilled mushrooms in the order Agaricales have the ability to release billions of spores. The puffball fungus Calvatia gigantea has been calculated to produce about five trillion basidiospores. Most basidiospores are forcibly discharged, and are thus considered ballistospores. These spores serve as the main air dispersal units for the fungi. The spores are released during periods of high humidity and generally have a night-time or pre-dawn peak concentration in the atmosphere.

<span class="mw-page-title-main">Partial veil</span> Mushroom anatomy

In mycology, a partial veil is a temporary structure of tissue found on the fruiting bodies of some basidiomycete fungi, typically agarics. Its role is to isolate and protect the developing spore-producing surface, represented by gills or tubes, found on the lower surface of the cap. A partial veil, in contrast to a universal veil, extends from the stem surface to the cap edge. The partial veil later disintegrates, once the fruiting body has matured and the spores are ready for dispersal. It might then give rise to a stem ring, or fragments attached to the stem or cap edge. In some mushrooms, both a partial veil and a universal veil may be present.

<span class="mw-page-title-main">Cystidium</span> Fungus cell type

A cystidium is a relatively large cell found on the sporocarp of a basidiomycete, often between clusters of basidia. Since cystidia have highly varied and distinct shapes that are often unique to a particular species or genus, they are a useful micromorphological characteristic in the identification of basidiomycetes. In general, the adaptive significance of cystidia is not well understood.

<span class="mw-page-title-main">Pileipellis</span> Mushroom 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 this layer as a macroscopic feature, while pileipellis refers to this structure as a microscopic layer. Pileipellis type is an important character in the identification of fungi. Pileipellis types include the cutis, trichoderm, epithelium, and hymeniderm types.

<span class="mw-page-title-main">Pileus (mycology)</span> Mushroom cap

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 (hymenophore) may consist of lamellae, tubes, or teeth, on the underside of the pileus. A pileus is characteristic of agarics, boletes, some polypores, tooth fungi, and some ascomycetes.

Limnoperdon is a fungal genus in the monotypic family Limnoperdaceae. The genus is also monotypic, as it contains a single species, the aquatic fungus Limnoperdon incarnatum. The species, described as new to science in 1976, produces fruit bodies that lack specialized structures such as a stem, cap and gills common in mushrooms. Rather, the fruit bodies—described as aquatic or floating puffballs—are small balls of loosely interwoven hyphae. The balls float on the surface of the water above submerged twigs. Experimental observations on the development of the fruit body, based on the growth on the fungus in pure culture, suggest that a thin strand of mycelium tethers the ball above water while it matures. Fruit bodies start out as a tuft of hyphae, then become cup-shaped, and eventually enclose around a single chamber that contains reddish spores. Initially discovered in a marsh in the state of Washington, the fungus has since been collected in Japan, South Africa, and Canada.

<i>Psilocybe makarorae</i> Species of fungus

Psilocybe makarorae is a species of psilocybin mushroom in the family Hymenogastraceae. Officially described as new to science in 1995, it is known only from New Zealand, where it grows on rotting wood and twigs of southern beeches. The fruit body (mushroom) has a brownish cap with lighter coloured margins, measuring up to 3.5 cm (1.4 in) wide. The cap shape is either conical, bell-shaped, or flat depending on the age of the mushroom, and it features a prominent umbo. Although the whitish stem does not form a true ring, it retains remnants of the partial veil that covers and protects the gills of young fruit bodies. P. makarorae mushrooms can be distinguished from the similar North American species Psilocybe caerulipes by microscopic characteristics such as the presence of cystidia on the gill faces (pleurocystidia), and cheilocystidia with more elongated necks. Based on the bluing reaction to injury, P. makarorae is presumed to contain the psychedelic compounds psilocybin and psilocin.

<i>Spongiforma thailandica</i> Species of fungus

Spongiforma thailandica is a species of fungus in the family Boletaceae, genus Spongiforma. The stemless sponge-like species, first described in 2009, was found in Khao Yai National Park in central Thailand, where it grows in soil in old-growth forests. The rubbery fruit body, which has a strong odor of coal-tar similar to Tricholoma sulphureum, consists of numerous internal cavities lined with spore-producing tissue. Phylogenetic analysis suggests the species is closely related to the Boletaceae genera Porphyrellus and Strobilomyces.

<i>Boletus rubroflammeus</i> Species of fungus

Boletus rubroflammeus is a species of bolete fungus in the family Boletaceae. First described from Michigan in 1971, it is found in the eastern United States and Mexico, where it grows in a mycorrhizal association with hardwood trees. The fruit bodies (mushrooms) of the fungus have caps that are deep red to purplish red, and dark red pores. The stem has coarse, dark red reticulations and a narrow yellow area at the top. All parts of the mushroom quickly stain blue when injured or cut. Lookalikes include Boletus flammans, a lighter-colored species that grows with conifers. Other similar species can be distinguished by differences in distribution, morphology, staining reaction, and microscopic characteristics. Boletus rubroflammeus mushrooms are poisonous, and can cause gastrointestinal distress if consumed.

<i>Royoporus badius</i> Species of fungus

Royoporus badius or Picipes badius, commonly known as the black-footed polypore or black-leg, is a species of fungus in the family Polyporaceae. It causes a white rot of hardwoods and conifers. The species is found in temperate areas of Asia, Australia, Europe, and North America. It has a dark brown or reddish-brown cap that reaches a diameter of 25 cm (9.8 in), and a stipe that is often completely black or brown at the top and black at the base.

Myriothele is a fungal genus in the family Polyporaceae. It is a monotypic genus, consisting of the single species Myriothele philippiae, a toothed crust fungus found in Réunion.

<i>Loweomyces fractipes</i> Species of fungus

Loweomyces fractipes is a species of poroid fungus in the family Steccherinaceae, and the type species of the genus Loweomyces. It is a widely distributed species, found in North America, Europe, Central America, South America, and Korea.

<span class="mw-page-title-main">Glossary of mycology</span> List of definitions of terms and concepts commonly used in the study of fungi

This glossary of mycology is a list of definitions of terms and concepts relevant to mycology, the study of fungi. Terms in common with other fields, if repeated here, generally focus on their mycology-specific meaning. Related terms can be found in glossary of biology and glossary of botany, among others. List of Latin and Greek words commonly used in systematic names and Botanical Latin may also be relevant, although some prefixes and suffixes very common in mycology are repeated here for clarity.

References