''Auricularia nigricans'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

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

in the family Auriculariaceae.

Basidiocarp 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 ...

s (fruitbodies} are gelatinous, ear-like, and grow on dead wood of broadleaf trees. It is found in southern and eastern Asia, North America, South America and the Caribbean. Asian examples were formerly considered as a separate species described as ''Auricularia polytricha''.

Taxonomy

The species was first described in 1788 as ''Peziza nigrescens'' by the Swedish botanist

Olof Swartz Olof Peter Swartz (21 September 1760 – 19 September 1818) was a Swedish botanist and taxonomist. He is best known for his taxonomic work and studies into pteridophytes. Biography Olof Swartz attended the University of Uppsala where he s ...

, based on a collection he made from

Jamaica Jamaica (; ) is an island country situated in the Caribbean Sea. Spanning in area, it is the third-largest island of the Greater Antilles and the Caribbean (after Cuba and Hispaniola). Jamaica lies about south of Cuba, and west of His ...

. In a later publication he changed the name to ''Peziza nigricans'', which was accepted by the Swedish mycologist Elias Magnus Fries. For abstruse nomenclatural reasons, Fries's

sanctioned name In mycology, a sanctioned name is a name that was adopted (but not necessarily coined) in certain works of Christiaan Hendrik Persoon or Elias Magnus Fries, which are considered major points in fungal taxonomy. Definition and effects Sanctioned ...

takes priority over Swartz's original name. In his monograph of ''

Auricularia ''Auricularia'' is a genus of fungi in the family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maint ...

'' species, American mycologist Bernard Lowy rejected the name as being "doubtful", preferring to call the species ''Auricularia polytricha''. Olof Swartz's original collection still exists, however, enabling the identity of his species to be confirmed. Molecular research, based on

cladistic Cladistics (; ) is an approach to biological classification in which organisms are categorized in groups ("clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived char ...

analysis of

DNA sequences A nucleic acid sequence is a succession of bases signified by a series of a set of five different letters that indicate the order of nucleotides forming alleles within a DNA (using GACT) or RNA (GACU) molecule. By convention, sequences are us ...

, has shown that ''Auricularia nigricans'' is distinct.

Description

''Auricularia nigricans'' forms thin, rubbery-gelatinous fruit bodies that are ear-shaped and up to across and thick. The fruitbodies occur singly or in clusters. The upper surface is densely

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 pl ...

and ash-grey to yellowish brown. The spore-bearing underside is smooth and pinkish to brown.

Microscopic characters

The microscopic characters are typical of the genus ''

''. The

basidia A basidium () is a microscopic sporangium (a spore-producing structure) found on the hymenophore of fruiting bodies of basidiomycete fungi which are also called tertiary mycelium, developed from secondary mycelium. Tertiary mycelium is highly- ...

are tubular, laterally septate, 50–75 × 3-6.5 µm. The

spores In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, ...

are allantoid (sausage-shaped), 14.5–17 × 5–7 µm. The surface hairs are 650–1080 µm long.

Similar species

'' Auricularia cornea'' is similar but has much shorter surface hairs 200–400 µm long.

Habitat and distribution

''Auricularia nigricans'' is a wood-rotting species, typically found on dead attached or fallen wood of broadleaf trees. It is widely distributed in the Americas, from Louisiana and the Caribbean south to Argentina, but is not currently known elsewhere.

References

{{Taxonbar, from=Q81165513 Auriculariales Fungi of South America Fungi of the Caribbean