Cyathus olla

Appearance

''Cyathus olla'' bears a resemblance to a miniature bird's nest containing eggs, hence the common name bird's nest fungi. The fruiting body, or ''peridium'', is roughly funnel-shaped, 10–18 mm tall and 8–12 mm wide. It is greyish yellow or greyish brown to fawn-colored and covered with even, fine-textured hairs on the outside surface. The inner surface is silver grey and smooth, often with faint transverse ridges. ''Cyathus olla'' is thick-walled, and flared outwards at the rim; the rim is typically wavy in outline. The 'eggs', or peridioles, typically number 8 to 10 in the cup, and they are white or grey in color, with a diameter of 2–4 mm—conspicuously larger than other ''Cyathus'' species. They are covered with a thin membrane called a ''tunica''.
Peridioles are often attached to the fruiting body by a funiculus, a structure of hyphae that is differentiated into three regions: the basal piece, which attaches it to the inner wall of the peridium, the middle piece, and an upper sheath, called the purse, connected to the lower surface of the peridiole. Inside the purse and middle piece is a coiled thread of interwoven hyphae called the funicular cord, attached at one end to the peridiole and at the other end to an entangled mass of hyphae called the hapteron. ''C. olla'' has a wide purse with an upper portion not easily distinguishable from the lower part.

A different form of this species, ''Cyathus olla'' forma ''anglicus'', originally reported from England by mycologist Curtis Gates Lloyd, has also been found in Oregon and Colorado in the USA, Alberta Canada, and in Argentina. This form is large, with cup openings up to 1.5 cm in diameter. Spores have dimensions of 11.5–12.5 × 7.5–9 µm.

The related species ''Cyathus earlei'' Lloyd closely resembles ''C. olla'', although mating analysis has shown that they are distinct species.

Distribution

Being a saprobic fungus, ''Cyathus olla'' obtains nutrients from the breakdown of dead organic matter, and as such is usually found growing on woody debris; specimens found growing on soil are usually attached to bits of wood or stems present in the soil. Brodie notes that this species usually grows in moist and shaded locations, although its discovery in the arid regions of Lima, Peru, suggest that it is tolerant of low-moisture conditions. It is the most abundant species of ''Cyathus'' found in Europe, and is also common in North America. Its range extends north to Sweden and far south in South America; it has also been reported in Australia, South Africa, Iran, and India.

Behavior

The life cycle of ''Cyathus olla'', which contains both haploid and diploid stages, is typical of taxa in the basidiomycetes that can reproduce both asexually , or sexually . Basidiospores produced in the peridioles each contain a single haploid nucleus. After dispersal, the spores germinate and grow into homokaryotic hyphae, with a single nucleus in each compartment. When two homokaryotic hyphae of different mating compatibility groups fuse with one another, they form a dikaryotic mycelia in a process called plasmogamy. After a period of time and under the appropriate environmental conditions, fruiting bodies may be formed from the dikaryotic mycelia. These fruiting bodies produce peridioles containing the basidia upon which new basidiospores are made. Young basidia contain a pair of haploid sexually compatible nuclei which fuse, and the resulting diploid fusion nucleus undergoes meiosis to produce haploid basidiospores. Meiosis in ''C. olla'' has been found to be similar to that of higher organisms.

Habitat

Being a saprobic fungus, ''Cyathus olla'' obtains nutrients from the breakdown of dead organic matter, and as such is usually found growing on woody debris; specimens found growing on soil are usually attached to bits of wood or stems present in the soil. Brodie notes that this species usually grows in moist and shaded locations, although its discovery in the arid regions of Lima, Peru, suggest that it is tolerant of low-moisture conditions. It is the most abundant species of ''Cyathus'' found in Europe, and is also common in North America. Its range extends north to Sweden and far south in South America; it has also been reported in Australia, South Africa, Iran, and India.

Cultural

Blackleg is a fungal disease of canola that results in major yield loss in affected crops. It overwinters on infected stubble that is left on farm fields, and can continue to produce spores, infecting future crops, until the stubble is buried or broken down completely. The observation that ''C. olla'' grows and fruits on canola stubble has led to research on the potential of this fungus to degrade canola stubble, and reduce the incidence of stubble-borne diseases like blackleg and blackspot. In a study of its lignin-degrading abilities, ''C. olla'' was shown to colonize canola, wheat, and barley residue, but appeared to have a preference for the woody taproots of canola as compared to the cereal residue.