''Oudemansiella australis'' is a species of

gilled mushroom An agaric () is a type of fungus 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. In the UK, agarics are called "mushrooms ...

in the family

Physalacriaceae The Physalacriaceae are a family of fungi in the order Agaricales. Species in the family have a widespread distribution, ranging from the Arctic, ('' Rhizomarasmius''), to the tropics, e.g. '' Gloiocephala'', and from marine sites ('' Mycaureola ...

. It is found in Australasia, where it grows on rotting wood. It produces

fruit bodies 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 cyc ...

that are white, with

caps Caps are flat headgear. Caps or CAPS may also refer to: Science and technology Computing * CESG Assisted Products Service, provided by the U.K. Government Communications Headquarters * Composite Application Platform Suite, by Java Caps, a Java ...

up to in diameter, attached to short, thick stems.

Taxonomy and classification

The species was reported as new to science by

Greta Stevenson Greta Barbara Stevenson (10 June 1911 – 18 December 1990) was a New Zealand botanist and mycologist. She described many new species of Agaricales (gilled mushrooms). Background and education Stevenson was born in Auckland, New Zealand, the ol ...

and G.M. Taylor in a 1964 publication, based on a specimen found in March, 1961. According to the 1986 arrangement of Pegler and Young, based largely on spore structure, ''Oudemansiella australis'' is classified in the

section Section, Sectioning or Sectioned may refer to: Arts, entertainment and media * Section (music), a complete, but not independent, musical idea * Section (typography), a subdivision, especially of a chapter, in books and documents ** Section sign ...

''Oudemansiella'' of genus ''

Oudemansiella ''Oudemansiella'' is a genus of fungi in the family Physalacriaceae. The genus contains about 15 species that are widely distributed in tropical and temperate regions. Yang and colleagues revised the genus in a 2009 publication, describing several ...

'', along with the species '' O. mucida'', '' O. venesolamellata'', and '' O. canarii''. In a more recent classification proposed by Yang and colleagues, ''O. australis'' is in section ''Oudemansiella'', which contains

tropical The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in the Southern Hemisphere at S. The tropics are also referred to ...

to south

temperate In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout t ...

species, such as '' O. platensis'', ''O. canarii'' and '' O. crassifolia''. These species are characterised by having an ixotrichoderm

cap cuticle The pileipellis is the uppermost layer of hyphae in the pileus of a fungal fruit body. It covers the trama, the fleshy tissue of the fruit body. The pileipellis is more or less synonymous with the cuticle, but the cuticle generally describes th ...

, meaning it is made of gelatinized filamentous

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 or ...

e of different lengths arranged in roughly parallel fashion. These hyphae are often mixed with inflated cells that usually occur in chains. New Zealand mycologist Geoff Ridley has proposed the

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contrast ...

"porcelain slimecap" for the mushroom.

Description

''Oudemansiella australis'' mushrooms have a

cap A cap is a flat headgear, usually with a visor. Caps have crowns that fit very close to the head. They made their first appearance as early as 3200 BC. Caps typically have a visor, or no brim at all. They are popular in casual and informal se ...

that is in diameter, and initially white becoming a light yellowish brown (

fawn Deer or true deer are hoofed ruminant mammals forming the family Cervidae. The two main groups of deer are the Cervinae, including the muntjac, the elk (wapiti), the red deer, and the fallow deer; and the Capreolinae, including the reindeer ...

) in age. It has a convex shape, but splits at the margins. The cap cuticle splits irregularly to reveal firm white flesh underneath. The

gills A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

are adnate, powdery white, and moderately distantly spaced. They are long and short intercalated, with deep with ribs at the base. The

stem Stem or STEM may refer to: Plant structures * Plant stem, a plant's aboveground axis, made of vascular tissue, off which leaves and flowers hang * Stipe (botany), a stalk to support some other structure * Stipe (mycology), the stem of a mushro ...

is long by thick, attached off-centre to the cap. It is white on the upper part, changing to fawn around the swollen base. The

flesh Flesh is any aggregation of soft tissues of an organism. Various multicellular organisms have soft tissues that may be called "flesh". In mammals, including humans, ''flesh'' encompasses muscle Skeletal muscles (commonly referred to as mu ...

is solid, white, and silky. 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 pinkish-tan spore print. A 3.5-centimeter ...

is white.

Spore 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, f ...

s are spherical or nearly so, measuring 24 by 21

µm The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Unit ...

, with thick walls (about 1 µm). They are non-

amyloid Amyloids are aggregates of proteins characterised by a Fibril, fibrillar morphology of 7–13 Nanometer, nm in diameter, a beta sheet (β-sheet) Secondary structure of proteins, secondary structure (known as cross-β) and ability to be Staining, ...

, and have a prominent

hilar Hilum may refer to: * Hilum (anatomy), a part of an organ where structures such as blood vessels and nerves enter the body * Hilum (botany), a scar on a seed or spore created by detachment See also * Fovea (disambiguation), another term associat ...

appendix (a depression in the surface where the spore was once connected to the

sterigmata In biology, a sterigma (pl. sterigmata) is a small supporting structure. It commonly refers to an extension of the basidium (the spore-bearing cells) consisting of a basal filamentous part and a slender projection which carries a spore at the ti ...

Habitat and distribution

The fungus grows on rotting wood. The first recorded collection was made in the open near a forest in Wainui Valley,

Wellington Wellington ( mi, Te Whanganui-a-Tara or ) is the capital city of New Zealand. It is located at the south-western tip of the North Island, between Cook Strait and the Remutaka Range. Wellington is the second-largest city in New Zealand by me ...

. It has since been found in Australia and

Papua New Guinea Papua New Guinea (abbreviated PNG; , ; tpi, Papua Niugini; ho, Papua Niu Gini), officially the Independent State of Papua New Guinea ( tpi, Independen Stet bilong Papua Niugini; ho, Independen Stet bilong Papua Niu Gini), is a country i ...

References

{{Taxonbar, from=Q7110260 Physalacriaceae Fungi described in 1964 Fungi of Australia Taxa named by Greta Stevenson Fungi of New Guinea