''Stilbum'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

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

in the family Chionosphaeraceae. Though many species were formerly referred to the genus, it is effectively

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

since the

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

, ''Stilbum vulgare'', currently has no close relative. ''Stilbum vulgare'' forms groups of minute, gelatinous,

synnema A synnema (plural ''synnemata'', also ''coremia''; derivation: "Threads together") is a large, erect reproductive structure borne by some fungi, bearing compact conidiophore A conidium ( ; : conidia), sometimes termed an asexual chlamydospore ...

-like

basidiocarps 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 no ...

(fruit bodies) up to 0.5 mm tall with a distinct stem and inflated, fertile head. Microscopically, it produces auricularioid (laterally septate)

basidia A basidium (: basidia) is a microscopic spore-producing structure found on the hymenophore of reproductive bodies of basidiomycete fungi. The presence of basidia is one of the main characteristic features of the group. These bodies are also ...

and

basidiospores 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 pr ...

that germinate by budding off

yeast Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom (biology), kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are est ...

cells. The species has been collected on rotting wood and old

agaric An agaric () is a type of fungal fruiting body characterized by the presence of a pileus (cap) that is clearly differentiated from the stipe (stalk), with lamellae (gills) on the underside of the pileus. It is a type of mushroom (or toadstool) ...

fruit bodies and may be a parasite of other fungi. It was originally described from Europe, but is also known from Asia, North America, and Australia.

Taxonomy

''Stilbum'' was described in 1790 by German

mycologist Mycology is the branch of biology concerned with the study of fungi, including their taxonomy, genetics, biochemical properties, and use by humans. Fungi can be a source of tinder, food, traditional medicine, as well as entheogens, poison, and ...

Heinrich Julius Tode. As well as ''Stilbum vulgare'', he included several other species of similar size, texture, and shape within the genus. In the following century, other authors added over 200 species to ''Stilbum'' on the same basis. Re-examination of specimens in the twentieth century showed, however, that nearly all these species were

anamorphic Anamorphic format is a cinematography technique that captures widescreen images using recording media with narrower native Aspect ratio (image), aspect ratios. Originally developed for 35 mm movie film, 35 mm film to create widescreen pres ...

members of the

Ascomycota Ascomycota is a phylum of the kingdom Fungi that, together with the Basidiomycota, forms the subkingdom Dikarya. Its members are commonly known as the sac fungi or ascomycetes. It is the largest phylum of Fungi, with over 64,000 species. The def ...

, many of them subsequently assigned to the genus '' Stilbella''. Some species originally described in the genus ''Stilbum'' remain unassigned and are treated as

nomina dubia In binomial nomenclature, a ''nomen dubium'' (Latin for "doubtful name", plural ''nomina dubia'') is a scientific name that is of unknown or doubtful application. Zoology In case of a ''nomen dubium,'' it may be impossible to determine whether a ...

since authentic material is lacking and the original descriptions are inadequate for identification.

References

{{Taxonbar, from=Q4050178 Agaricostilbales Basidiomycota genera Taxa described in 1790