''Xylaria polymorpha'', commonly known as dead man's fingers, is a cosmopolitan

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 ...

fungus. It is characterized by its elongated upright, clavate, or strap-like

stromata The ''Stromata'' (), a mistake for ''Stromateis'' (Στρωματεῖς, "Patchwork," i.e., ''Miscellanies''), attributed to Clement of Alexandria (c. 150 – c. 215), is the third of a trilogy of works regarding the Christian life. The oldest ...

poking up through the ground, much like fingers.

Taxonomy

The genus ''

Xylaria ''Xylaria'' is a genus of ascomycetous fungi commonly found growing on dead wood. The name comes from the Greek ''xýlon'' meaning ''wood'' (see xylem). 'Outline of Fungi and fungus-like taxa' by Wijayawardene et al. lists up to (ca. 571) spe ...

'' contains about 100 species of

cosmopolitan Cosmopolitan may refer to: Internationalism * World citizen, one who eschews traditional geopolitical divisions derived from national citizenship * Cosmopolitanism, the idea that all of humanity belongs to a single moral community * Cosmopolitan ...

fungi. 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 ...

''polymorpha'' means "many forms". As its name suggests, it has a variable but often club-shaped fruiting body ( stroma) resembling burned wood.

Description

Belonging to the phylum of fungus known as

Ascomycetes 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 de ...

(division Mycota) known as the sac fungi, they are characterized by a saclike structure, the

ascus An ascus (; : asci) is the sexual spore-bearing cell produced in ascomycete fungi. Each ascus usually contains eight ascospores (or octad), produced by meiosis followed, in most species, by a mitotic cell division. However, asci in some gen ...

, which contains anything from four to eight

ascospore In fungi, an ascospore is the sexual spore formed inside an ascus—the sac-like cell that defines the division Ascomycota, the largest and most diverse Division (botany), division of fungi. After two parental cell nucleus, nuclei fuse, the ascu ...

s in the sexual stage. The sac fungi are separated into subgroups based on whether asci arise singly or are borne in one of several types of fruiting structures, or ascocarps, and on the method of discharge of the ascospores. Unlike some species in this class, ''X. polymorpha'' is inedible. Often this fungus is found with a multitude of separate "digits", but at times the individual parts will be fused together. In maturity, the fruiting bodies can be tall, externally colored black or brown, sometimes with shades of blue or green. It is white on the inside, with a blackened dotted area all around. This blackened surrounding area is made up of tiny structures called

perithecia 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 ...

. The perithecia hold a layer of asci which contain the ascospores. The asci elongate into the

ostiole An ''ostiole'' is a small hole or opening through which algae or fungi release their mature spores. The word is a diminutive of wikt:ostium, "ostium", "opening". The term is also used in higher plants, for example to denote the opening of the ...

, and discharge the ascospores outward. The spore distribution is a lengthy process, sometimes taking several months to complete. The

spore print 300px, Making a spore print of the mushroom ''Volvariella volvacea'' shown in composite: (photo lower half) mushroom cap laid on white and dark paper; (photo upper half) cap removed after 24 hours showing warm orange ("tussock") color spore print. ...

is black. In springtime this fungus often produces a layer of white or bluish asexual spores called

conidia A conidium ( ; : conidia), sometimes termed an asexual chlamydospore or chlamydoconidium (: chlamydoconidia), is an asexual, non- motile spore of a fungus. The word ''conidium'' comes from the Ancient Greek word for dust, ('). They are also ...

, which grow on its surface and surrounding area.

Distribution and habitat

''X. polymorpha'' is geographically distributed across all six inhabited continents. It is a common inhabitant of forest and woodland areas, usually growing from the bases of rotting or injured tree stumps and decaying wood. It has also been known to colonize substrates like woody legume pods,

petiole Petiole may refer to: *Petiole (botany), the stalk of a leaf, attaching the blade to the stem *Petiole (insect anatomy) In entomology, petiole is the technical term for the narrow waist of some hymenopteran insects, especially ants, bees, and ...

s, and herbaceous stems.

References

External links

Index Fungorum

USDA ARS Fungal Database

Images

Dead Man's Fingers

Mushroom Observer, ''Xylaria polymorpha''
nowiki/> {{Taxonbar, from=Q241408 Fungal tree pathogens and diseases Xylariales Fungi of Europe Inedible fungi Taxa named by Christiaan Hendrik Persoon Fungi described in 1824 Fungus species