''Aureofungus'' is an extinct

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 "unispe ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of gilled

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 order Agaricales. At present it contains the single

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 ...

''Aureofungus yaniguaensis''. The genus is solely known from the early

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

Burdigalian The Burdigalian is, in the geologic timescale, an age or stage in the early Miocene. It spans the time between 20.43 ± 0.05 Ma and 15.97 ± 0.05 Ma (million years ago). Preceded by the Aquitanian, the Burdigalian was the first and longest w ...

stage,

Dominican amber Dominican amber is amber from the Dominican Republic derived from resin of the extinct tree '' Hymenaea protera''. Dominican amber differentiates itself from Baltic amber by being nearly always transparent, and it has a higher number of fossil inc ...

deposits on the island of Hispaniola. ''Aureofungus'' is one of only four known agarics fungus species known in the fossil record and the third to be described from Dominican amber.

History and classification

The genus is known only from the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of sever ...

fossil, which is a single fruiting body currently residing in the private collection owned by Yale Goldman of

Connecticut Connecticut () is the southernmost state in the New England region of the Northeastern United States. It is bordered by Rhode Island to the east, Massachusetts to the north, New York to the west, and Long Island Sound to the south. Its capita ...

United States. The specimen was collected in August 2000 from the Yanigua Mine, El Valle in the eastern

Dominican Republic The Dominican Republic ( ; es, República Dominicana, ) is a country located on the island of Hispaniola in the Greater Antilles archipelago of the Caribbean region. It occupies the eastern five-eighths of the island, which it shares with ...

. It was first studied by a group of researchers led by Dr. David Hibbett of the

Clark University Clark University is a private research university in Worcester, Massachusetts. Founded in 1887 with a large endowment from its namesake Jonas Gilman Clark, a prominent businessman, Clark was one of the first modern research universities in the ...

. Hibbett '' et al'' published their 2003

type description A species description is a formal description of a newly discovered species, usually in the form of a scientific paper. Its purpose is to give a clear description of a new species of organism and explain how it differs from species that have be ...

in the journal ''

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 ...

''. The generic epithet ''Aureofungus'' is

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

in derivation and means "golden fungus" while the specific epithet "''yaniguaensis''" was coined by the authors from "Yanigua" in recognition of the type locality. When described ''Aureofungus yaniguaensis'' was the fourth species of fossil agaric fungus to be described. Two species '' Coprinites dominicana'' and '' Protomycena electra'' are also from the amber mines of the Dominican Republic, while the third species '' Archaeomarasmius leggeti'' is from the older

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...

age

New Jersey Amber New Jersey Amber, sometimes called Raritan amber, is amber found in the Raritan and Magothy Formations of the Central Atlantic (Eastern) coast of the United States. It is dated to the Late Cretaceous, Turonian age, based on pollen analysis of t ...

. With the 2007 publication of a fifth extinct agaric species, '' Palaeoagaracites antiquus'' the age for the order was pushed back to the

Albian The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous Epoch/ Series. Its approximate time range is 113.0 ± 1.0 Ma to 100.5 ± 0 ...

(approximately 100 Ma).

Description

The holotype of ''Aureofungus'' is a

fruiting body The sporocarp (also known as fruiting body, fruit body or fruitbody) of fungi is a multicellular structure on which spore-producing structures, such as basidia or asci, are borne. The fruitbody is part of the sexual phase of a fungal life cy ...

and associated

basidiospore 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 ...

s. The pileus is in diameter and has a convex shape sporting a broad raised central region. The lightly textured flesh is yellow-brown in coloration and sports a striated, incurved margin. The

lamellae Lamella (plural lamellae) means a small plate or flake in Latin, and in English may refer to: Biology * Lamella (mycology), a papery rib beneath a mushroom cap * Lamella (botany) * Lamella (surface anatomy), a plate-like structure in an animal * ...

or gills are subdistant and lacking lamellulae, short gills which do not reach the edge of the pileus. The pileus is centered on the stipe, which is long and lacking the volva, annulus and any rhizoids. The basidiospores associated with the fruiting body are grouped in masses and appear to have been produced by the fruiting body after entombment in the resin. Each basidiospore is broadly elliptic and approximately 4.0 μm by 3.3μm. These combined characters indicate a possible relation to the modern

Tricholomataceae The Tricholomataceae are a large family of mushrooms within the Agaricales. Originally a classic " wastebasket taxon", the family included any white-, yellow-, or pink-spored genera in the Agaricales not already classified as belonging to e.g. th ...

or some of the "dusky-spored taxa" such as '' Coprinellus disseminatus''. However the thickness of the amber entombing the specimen prevented study finer details, such as spore ornamentation and pileus texture, which would have clarified the relations. As such Hibbett ''et al'' left the placement of ''Aureofungus'' as Agaricales ''

incertae sedis ' () or ''problematica'' is a term used for a taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertain ...

''. Despite the lack of visible details, enough characters are present to distinguish ''Aureofungus'' from the three other known amber fossil species.

References

{{Taxonbar, from=Q4822293 †Aureofungus Monotypic Agaricales genera Prehistoric fungi Neogene fungi Burdigalian life †Aureofungus Natural history of Hispaniola Fossils of the Dominican Republic Neogene Dominican Republic Dominican amber Fossil taxa described in 2003

History and classification

Description

See also

References