A cystidium (PL: 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 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.
Cystidia may occur on the edge of a lamella (or analogous hymenophoral structure) (cheilocystidia), on the face of a lamella (pleurocystidia), on the surface of the cap (dermatocystidia or pileocystidia), on the margin of the cap (circumcystidia) or on the stipe (caulocystidia). Especially the pleurocystidia and cheilocystidia are important for identification within many genera. Sometimes the cheilocystidia give the gill edge a distinct colour which is visible to the naked eye or with a hand lens.
Chrysocystidia are cystidia whose contents contain a distinct refractive yellow body, that becomes more deeply yellow when exposed to ammonia or other alkaline compounds. Chrysocystidia are characteristic of many (though not all) members of the agaric family Strophariaceae.
Gloeocystidia have an oily or granular appearance under the microscope. Like gloeohyphae, they may be yellowish or clear (hyaline) and can sometimes selectively be coloured by sulphovanillin or other reagents. [1] Metuloids are thick-walled cystidia with an apex having any of several distinct shapes. [2]
Inocybe is a large genus of mushroom-forming fungi with over 1400 species, including all forms and variations. Members of Inocybe are mycorrhizal, and some evidence shows that the high degree of speciation in the genus is due to adaptation to different trees and perhaps even local environments.
Mythicomyces is a fungal genus in the family Mythicomycetaceae. A monotypic genus, it contains the single species Mythicomyces corneipes, first described by Elias Fries in 1861. The fungus produces fruit bodies with shiny yellowish-orange to tawny caps that are 1–3 cm (0.4–1.2 in) in diameter. These are supported by stems measuring 2–5.7 cm (0.8–2.2 in) long and 1–2 mm thick. A rare to uncommon species, it is found in northern temperate regions of North America and Europe, where it typically fruits in groups, in wet areas of coniferous forests. There are several species with which M. corneipes might be confused due to a comparable appearance or similar range and habitat, but microscopic characteristics can be used to reliably distinguish between them.
Atheniella flavoalba, which has the recommended name of ivory bonnet in the UK, is a species of agaric in the family Cyphellaceae. The cap is initially conical, before becoming convex and then flat; it may reach up to 1.5 cm (0.6 in) across. The cap is ivory-white to yellowish white, sometimes more yellowish at the center. The tubular stems are up to 8 cm (3.1 in) long and 2.5 mm (0.10 in) thick, and have long, coarse white hairs at their bases. Atheniella flavoalba is found in Europe, the Middle East, and North America, where it grows scattered in pastures or in dense groups under conifers and on humus in oak woods.
Mycena inclinata, commonly known as the clustered bonnet or the oak-stump bonnet cap, is a species of mushroom in the family Mycenaceae. The doubtfully edible mushroom has a reddish-brown bell-shaped cap up to 4.5 cm (1.8 in) in diameter. The thin stem is up to 9 cm (3.5 in) tall, whitish to yellow-brown at the top but progressively becoming reddish-brown towards the base in maturity, where they are covered by a yellowish mycelium that can be up to a third of the length of the stem. The gills are pale brown to pinkish, and the spore print is white. It is a widespread saprobic fungus, and has been found in Europe, North Africa, Asia, Australasia, and North America, where it grows in small groups or tufts on fallen logs and stumps, especially of oak. British mycologist E.J.H. Corner has described two varieties of the mushroom from Borneo. Lookalike species with which M. inclinata may be confused include M. galericulata and M. maculata.
Mycena leptocephala, commonly known as the nitrous bonnet, is a species of fungus in the family Mycenaceae. The mushrooms have conical grayish caps that reach up to 3 cm (1.2 in) in diameter, and thin fragile stems up to 5 cm (2.0 in) long. The gills are gray and distantly spaced. The spores are elliptical, typically measure 7–10 by 4–6 μm, and are white in deposit. When viewed under a light microscope, the gills have abundant spindle-shaped cystidia on the gill edges, but few on the gill faces. The mushroom is found in North America, Asia, and Europe where it grows singly or in groups on conifer needles, cones and sticks on the forest floor. It has a distinctive odor of bleach; the edibility is unknown. Similar species include Mycena alcalina, M. austera, and M. brevipes.
Psilocybe aztecorum is a species of psilocybin mushroom in the family Hymenogastraceae. Known from Arizona, Colorado, central Mexico, India and Costa Rica, the fungus grows on decomposing woody debris and is found in mountainous areas at elevations of 2,000 to 4,000 m, typically in meadows or open, grassy conifer forests. The mushrooms have convex to bell-shaped caps 1.5–2 cm (0.6–0.8 in) in diameter, atop slender cylindrical stems that are up to 7.5 cm (3.0 in) long. The color of the caps changes with variations in hydration, ranging from dark chestnut brown to straw yellow or whitish when dry. The base of the stem is densely covered with conspicuous white rhizomorphs, a characteristic uncommon amongst Psilocybe species.
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.
Psilocybe tasmaniana is a species of coprophilous agaric fungus in the family Hymenogastraceae. It was described by Gastón Guzmán and Roy Watling in 1978 as a small tawny orange mushroom that grows on dung, with a slight blueing reaction to damage, known only from Tasmania and southeastern Australia. It was likened to Psilocybe subaeruginosa although characteristics, appearance, and the association with dung were not typical for that species. As a blueing member of the genus Psilocybe it contains the psychoactive compounds psilocin and psilocybin.
Mycena clariviolacea is a mushroom in the family Mycenaceae. First reported as a new species in 2007, it is known only from Kanagawa, Japan, where it fruits on dead fallen twigs in forests dominated by oak and chinquapin trees. Distinctive features of this species are found in its medium-sized, dark violet fruit bodies, with caps up to 25 mm (0.98 in) in diameter and slender stems that are about 30 to 40 mm long. Microscopic characteristics include the amyloid spores, the club-shaped cheilocystidia that are covered with one or more, knob-like, apical protuberances, the absence of pleurocystidia, and the cylindrical, diverticulate caulocystidia.
Mycena fonticola is a species of fungus in the family Mycenaceae. First reported in 2007, it is known only from central Honshu, in Japan, where it grows on dead leaves and twigs in low-elevation forests dominated by oak trees. The fruit body of the fungus has a smooth, violet-brown cap up to 2.5 cm (1.0 in) in diameter, and a slender stem up to 10 cm (3.9 in) long. Distinguishing microscopic characteristics of the mushroom include the relatively large, distinctly amyloid spores, the smooth, spindle-shaped cheilocystidia, the absence of pleurocystidia, the diverticulate hyphae of the cap cuticle, and the absence of clamp connections.
Mycena fuscoaurantiaca is a species of mushroom in the family Mycenaceae. First reported as a new species in 2007, the diminutive mushroom is only found in Kanagawa, Japan, where it grows on dead fallen twigs in lowland forests dominated by hornbeam (Carpinus) and Chinese evergreen oak trees. The mushroom has a brownish-orange conical cap that has grooves extending to the center, and reaches up to 11 mm (0.43 in) in diameter. Its slender stem is colored similarly to the cap, and long—up to 60 mm (2.4 in) tall. Microscopic characteristics include the weakly amyloid spores, the smooth, swollen cheilocystidia and pleurocystidia with long rounded tips, the diverticulate hyphae of the cap cuticle, and the absence of clamp connections.
Mycena lanuginosa is a species of mushroom in the family Mycenaceae. First collected in 2000 and reported as a new species in 2007, it is known only from lowland oak-dominated forests in central Honshu in Japan. The small mushroom is characterized by its grooved, grayish-brown to violet-brown cap up to 11 mm (0.43 in) in diameter, and the slender grayish-brown to reddish-brown stem covered with minute, fine, soft hairs. The mushroom produces amyloid spores. Microscopic distinguishing features include the smooth, spindle-shaped cheilocystidia and pleurocystidia and the diverticulate elements in the outer layer of the cap and the stem.
Mycena multiplicata is a species of mushroom in the family Mycenaceae. First described as a new species in 2007, the mushroom is known only from Kanagawa, Japan, where it grows on dead fallen twigs in lowland forests dominated by oak. The mushroom has a whitish cap that reaches up to 13 mm (0.51 in) in diameter atop a slender stem 15 to 20 mm long by 1 to 1.3 mm thick. On the underside of the cap are whitish, distantly spaced gills that are narrowly attached to the stem. Microscopic characteristics of the mushroom include the amyloid spores, the pear-shaped to broadly club-shaped cheilocystidia covered with a few to numerous, unevenly spaced, cylindrical protuberances, the lack of pleurocystidia, and the diverticulate hyphae in the outer layer of the cap and stem. The edibility of the mushroom is unknown.
Mycena nidificata is a species of fungus in the family Mycenaceae of the Agaricales. First collected in 2000 and reported as a new species in 2007, it is known only from Kanagawa, Japan, where it grows on the floor of oak forests. The dark brown irregularly wrinkled cap measures up to 25 mm (1.0 in) in diameter. The cap is supported by a thin stem up to 50 mm (2.0 in) long, which is covered at the base by a whitish hairlike growth, and attached to white, cord-like rhizomorphs—aggregations of mycelium that resemble plant roots. The underside of the cap features thin, distantly spaced grayish gills that have distinct veins running between them. At a microscopic level, distinguishing characteristics include the inamyloid spores, the club-shaped cheilocystidia with finger-like appendages, the diverticulate cells in the outer layer of cap and stem, and the presence of clamp connections.
Psilocybe washingtonensis is a species of psilocybin mushroom in the family Hymenogastraceae. It is similar in appearance to Psilocybe pelliculosa and P. silvatica, and a microscope is needed to reliably distinguish between them.
Lepiota babruzalka is an agaric mushroom of the genus Lepiota in the order Agaricales. Described as new to science in 2009, it is found in Kerala State, India, where it grows on the ground in litterfall around bamboo stems. Fruit bodies have caps that measure up to 1.3 cm (0.5 in) in diameter, and are covered with reddish-brown scales. The cap is supported by a long and slender stem up to 4.5 cm (1.8 in) long and 1.5 millimetres (0.1 in) thick. One of the distinguishing microscopic features of the species is the variably shaped cystidia found on the edges of the gills.
Lepiota harithaka is an agaric mushroom of the genus Lepiota in the order Agaricales. It was described as new to science in 2009. Found in Kerala State, India, fruit bodies of the fungus grow on the ground among bamboo roots.
Lepiota ananya is a gilled mushroom of the genus Lepiota in the order Agaricales. Known only to come from Kerala State, India, it was described as new to science in 2009.
Strobilurus tenacellus, commonly known as the pinecone cap, is a species of agaric fungus in the family Physalacriaceae. It is found in Asia and Europe, where it grows on the fallen cones of pine and spruce trees. The fruit bodies (mushrooms) are small, with convex to flat, reddish to brownish caps up to 15 mm (0.6 in) in diameter, set atop thin cylindrical stems up to 4–7.5 cm (1.6–3.0 in) long with a rooting base. A characteristic microscopic feature of the mushroom is the sharp, thin-walled cystidia found on the stipe, gills, and cap. The mushrooms, sometimes described as edible, are too small to be of culinary interest. The fungus releases compounds called strobilurins that suppress the growth and development of other fungi. Derivatives of these compounds are used as an important class of agricultural fungicides.
Volvopluteus michiganensis is a species of mushroom in the family Pluteaceae. It was originally described under the name Pluteus michiganensis but molecular studies have placed it in the Volvopluteus, a genus described in 2011. The cap of this mushroom is about 7–9 cm (2.8–3.5 in) in diameter, gray, and has a cracked margin that is sticky when fresh. The gills start out as white but they soon turn pink. The stipe is white and has a volva at the base. Microscopical features and DNA sequence data are of great importance for separating this taxon from related species. V. michiganensis is a saprotrophic fungus that was originally described as growing on sawdust. It has only been reported from Michigan (USA) and the Dominican Republic.