''Chlorociboria aeruginascens'' is a

saprobic 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 of mushroom, commonly known as the blue stain, green elfcup or the green wood cup because of its characteristic small, green, saucer-shaped fruit bodies. The actual fruit bodies are infrequently seen, with the fungus usually observed through the green staining of wood it causes.

Taxonomy

The

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

is derived from the

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

roots ''aerug''- ("blue-green") and ''ascens'' ("becoming"). Some authors have used a variant spelling of the specific epithet, ''aeruginescens''.Seaver FJ. (1936). Photographs and descriptions of cup-fungi-XXIV. ''Chlorociboria''. ''

Mycologia ''Mycologia'' is a peer-reviewed scientific journal that publishes papers on all aspects of the fungi, including lichens. It first appeared as a bimonthly journal in January 1909, published by the New York Botanical Garden under the editorship of W ...

'' 28: 390–394.Seaver FJ. (1951). ''The North American Cup-Fungi (Inoperculates)''. New York. Pp. 1–428.

Description

This species has apothecia (cup-shaped

ascocarp An ascocarp, or ascoma (: ascomata), 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. Ascoc ...

s) that are usually attached laterally, often less than in diameter, collapsing laterally and becoming rolled inwards when dry. The outer tissue layer of the apothecium, known as the ectal excipulum, has a delicate

tomentose Trichomes (; ) are fine outgrowths or appendages on plants, algae, lichens, and certain protists. They are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae. A covering of any kind of hair on a plant ...

surface composed of hair-like, straight or sometimes coiled, smooth

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 o ...

e. The stipe is typically less than 3 mm long, with a central or eccentric attachment to the apothecia. The

spore In biology, a spore is a unit of sexual reproduction, sexual (in fungi) or asexual reproduction that may be adapted for biological dispersal, dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores fo ...

s are roughly spindle-shaped (

fusiform Fusiform (from Latin ''fusus'' ‘spindle’) means having a spindle (textiles), spindle-like shape that is wide in the middle and tapers at both ends. It is similar to the lemon (geometry), lemon-shape, but often implies a focal broadening of a ...

), smooth, and 5–8 by 0.7–2.8

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 ...

. The spore print is white. Apothecia grow on bark-free wood, especially

oak An oak is a hardwood tree or shrub in the genus ''Quercus'' of the beech family. They have spirally arranged leaves, often with lobed edges, and a nut called an acorn, borne within a cup. The genus is widely distributed in the Northern Hemisp ...

, part of which at least is stained greenish by the

mycelium Mycelium (: mycelia) is a root-like structure of a fungus consisting of a mass of branching, thread-like hyphae. Its normal form is that of branched, slender, entangled, anastomosing, hyaline threads. Fungal colonies composed of mycelium are fo ...

. The abundant

paraphyses Paraphyses are erect sterile filament-like support structures occurring among the reproductive apparatuses of fungi, ferns, bryophytes and some thallophytes. The singular form of the word is paraphysis. In certain fungi, they are part of the f ...

, which may be entwined, are 55–95 by 1.5–2 μm,

filiform Filiform, thread or filament like, can refer to: * Filiform, a common term used in botany to describe a thread-like shape *Filiform, or filiform catheter, a medical device whose component parts or segments are all cylindrical and more or less un ...

, and

septate In biology, a septum (Latin for ''something that encloses''; septa) is a wall, dividing a cavity or structure into smaller ones. A cavity or structure divided in this way may be referred to as septate. Examples Human anatomy * Interatrial se ...

with an unswollen, unbent apex that often extends beyond the level of the asci tips.

Similar species

The species is distinguished from the closely related '' Chlorociboria aeruginosa'' by having smaller spores. Although some authors have in the past failed to recognize any appreciable differences between the two species, Ramamurthi and colleagues noteRamamurthi CS, Korf RP, Batra LR. (1957). A revision of the North American species of ''Chlorociboria'' (Sclerotiniaceae). ''

'' 49(6): 854–863. that not only are the spore sizes different, but ''C. aeruginascens'' have smooth tomentum hyphae, in contrast with the roughened hyphae of ''C. aeruginosa''. ''C. aeruginascens'' is inedible.

"Green oak"

This species contains a

quinone The quinones are a class of organic compounds that are formally "derived from aromatic compounds benzene.html" ;"title="uch as benzene">uch as benzene or naphthalene] by conversion of an even number of –CH= groups into –C(=O)– groups with ...

pigment A pigment is a powder used to add or alter color or change visual appearance. Pigments are completely or nearly solubility, insoluble and reactivity (chemistry), chemically unreactive in water or another medium; in contrast, dyes are colored sub ...

called

xylindein Xylindein is a quinone pigment, a dimeric naphthoquinone derivative. It is produced by fungi in the genus ''Chlorociboria''. This pigment causes green staining of wood infected by the fungi. Etymology This pigment was firstly extracted in 1868 b ...

, a dimeric naphthoquinone derivative, whose structure was determined by spectroscopic means in the 1960s and later confirmed by

X-ray crystallography X-ray crystallography is the experimental science of determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to Diffraction, diffract in specific directions. By measuring th ...

. It is this compound that is responsible for the characteristic bluish-green stain of wood infected by this species, used today in decorative woodworking such as

Tunbridge ware Tunbridge ware is a form of decoratively inlaid woodwork, typically in the form of boxes, that is characteristic of Tonbridge and the spa town of Royal Tunbridge Wells in Kent in the 18th and 19th centuries. The decoration typically consists of a ...

and

parquetry Parquet (; French for "a small compartment") is a geometric mosaic of wood pieces used for decorative effect in flooring. Parquet patterns are often entirely geometrical and angular—squares, triangles, Lozenge (shape), lozenges—but may co ...

. The use of this wood, known as "green oak", goes back to 15th-century Italy, where it was used in

intarsia Intarsia is a form of wood inlaying that is similar to marquetry. The practice dates from before the seventh century AD. The technique inserts sections of wood (at times with contrasting ivory or bone, or mother-of-pearl) within the solid wood ...

panels made by Fra Giovanni da Veroni.Blanchette RA, Wilmering AM, Baumeister M. (1992). The use of green-stained wood caused by the fungus ''Chlorociboria'' in intarsia masterpieces from the 15th century. ''Holzforschung'' 46(3): 225–232.

References

External links

Index Fungorum
{{Taxonbar, from=Q1773888 Helotiaceae Fungi of Europe Fungi described in 1957 Inedible fungi Fungus species