''Leratiomyces ceres'', commonly known as the Redlead Roundhead, is mushroom which has a bright red to orange cap and dark purple-brown
spore deposit
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 ...
. It is usually found growing gregariously on
wood chips
Woodchips are small- to medium-sized pieces of wood formed by cutting or chipping larger pieces of wood such as trees, branches, logging residues, stumps, roots, and wood waste.
Woodchips may be used as a biomass solid fuel and are raw material f ...
and is one of the most common and most distinctive mushrooms found in that habitat. It is common on wood chips and lawns in North America, Europe, Australia, New Zealand and elsewhere. The name ''Stropharia aurantiaca'' has been used extensively but incorrectly for this mushroom (together with a number of similar synonyms).
Description
''L. ceres'' may be described as follows.
* Cap: 2 to 6 cm in diameter, with thin flesh and a bright red to orange top which is convex to plane in age. Has white partial veil remnants when young. The cap surface is usually dry, but can be slightly viscid when moist.
* Gills: White to pale grey at first, later darker purple/brown or purplish grey with whitish edges. Attached (adnexed to adnate) and often notched.
* Stipe: Whitish, often with dark orange stains in age (most evident around base), 3–6 cm long and 0.5 to 1 cm wide, equal to slightly larger at the base, which often has mycelium attached. The veil is thin and leaves a fragile, indistinct ring, sometimes missing with age. The stalk is smooth above the ring zone and is fluffy with tiny scales below, which often wash off in rain.
* Spores: Dark purple/brown. 10–13.5 × 6–8.5 m. Elliptical and smooth.
* Other microscopic features:
Chrysocystidia
A cystidium (plural cystidia) is a relatively large cell found on the sporocarp of a basidiomycete (for example, on the surface of a mushroom gill), often between clusters of basidia. Since cystidia have highly varied and distinct shapes that ar ...
are present both on the edges and on the faces of the gills.
File:Leratiomyces ceres (2004).jpg, Leratiomyces ceres
File:Leratiomyces ceres (formerly known as Stropharia aurantiaca, Hypholoma aurantiaca, Naematoloma aurantiaca, etc.) (15809298769).jpg
File:Leratiomyces ceres spores 1000x.JPG, Spores 1000×
Naming
There has been some confusion between ''L. ceres'', which has a fairly thick white stem, and '' L. squamosus'' var. ''thaustus'', which has a slender stem and prominent scales below the ring zone (although the two taxa are quite easy to distinguish by sight). Around 1885 Mordecai Cubitt Cooke originated the names ''Agaricus squamosus'' f. ''aurantiacus'' and ''Agaricus thraustus'' var. ''aurantiacus'', and this later gave rise to the name ''Stropharia aurantiaca''. This name is defined by Cooke's illustration to his ''Handbook of British Fungi'' and in 2004 Richard Fortey discovered that this illustration was not of ''L. ceres'', as had generally been assumed, but it was ''L. squamosus'' var. ''thaustus''. Thus the name ''aurantiaca'' is best avoided, being wrong when applied to ''L. ceres''.
File:Leratiomyces squamosus var. thraustus (Kalchbr.) Bridge & Spooner 486358.jpg, ''L. squamosus'' var. ''thaustus''
The name ''Agaricus ceres'' was created in 1888 by
Cooke
Cooke is a surname derived from the occupation of cook. Notable people with the surname include:
* Alexander Cooke (died 1614), English actor
* Alfred Tyrone Cooke, of the Indo-Pakistani wars
* Alistair Cooke KBE (1908–2004), British-American j ...
and
Massee
Massee is the surname of the following people:
*George Edward Massee (1845–1917), English mycologist, plant pathologist, and botanist
*J. C. Massee (1871–1965), American Christian fundamentalist
*May Massee (1881–1966), American children's b ...
for the white-stemmed species, and was reclassified as ''Psilocybe ceres'' (in 1891) and ''Leratiomyces ceres'' (in 2008).
Gymnopilus sapineus
''Gymnopilus sapineus'', commonly known as the scaly rustgill or common and boring gymnopilus, is a small and widely distributed mushroom which grows in dense clusters on dead conifer wood. It has a rusty orange spore print and a bitter taste. ...
'', ''
Psathyrella gracilis
''Psathyrella corrugis'', is the type species of the basidiomycete fungus genus ''Psathyrella'' and family Psathyrellaceae. Originally described from Europe as ''Agaricus corrugis'', the species is considered non-toxic but lacking in flesh, flavo ...
Tubaria furfuracea
''Tubaria furfuracea'', commonly known as the scurfy twiglet, is a common species of agaric fungus in the family Tubariaceae. It was first described by Christiaan Hendrik Persoon in 1801 as a species of ''Agaricus''. French mycologist Claude-Cas ...
''.
In psilocybin mushroom hunting communities in Australia and New Zealand, ''L. ceres'' (or "Larrys" as commonly nicknamed) are scorned as lookalikes and imposters of ''Psilocybe'' species on wood chip. Prolific growth in the same habitats and a similar appearance from afar can give false hope of a large bounty, but on closer inspection the species are not particularly alike.