''Conocybe rickenii'' is a mushroom from the genus ''

Conocybe ''Conocybe'' is a genus of mushrooms with ''Conocybe tenera'' as the type species and at least 243 other species. There are at least 50 different species in North America. Most have a long, thin fragile stipe and are delicate, growing in grassl ...

''. Its edibility is disputed, and it has the appearance of a typical

little brown mushroom Mushroom hunting, mushrooming, mushroom picking, mushroom foraging, and similar terms describe the activity of gathering mushrooms in the wild, typically for culinary use. This practice is popular throughout most of Europe, Australia, Japan, ...

with a small, conical

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 ...

, and long, thin

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 ...

. In colour, it is generally a cream-brown, lighter on the stem, and it has a thin layer of

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 ...

with no distinct smell or taste. It is a coprophilous fungus, feeding off dung and it is most common on very rich soil or growing directly from dung. It can be found in Europe, Australia and Pacific islands.

Taxonomy

''Conocybe rickenii'' was first described in 1930 by German mycologist

Julius Schäffer Julius Schäffer (3 June 1882 – 21 October 1944) was a German mycologist. His contributions include studies on the Agaricales The fungal order Agaricales, also known as gilled mushrooms (for their distinctive gills) or euagarics, contains some ...

and named ''Galera rickenii''. It was reclassified by

Robert Kühner Robert Kühner (15 March 1903 in Paris – 27 February 1996 in Lyon) was a French mycologist most notable for reviewing many forms of agaric (mushroom fungus) genera. He studied at the Sorbonne, afterwards from 1921 until 1932, he was worki ...

, who placed it in the genus ''Conocybe''.

Description

''Conocybe rickenii'' has a conical cap of across, which is an ochre-brown, sometimes becoming a little more grey at the centre. The stem is typically in height, by in thickness, and is whitish cream, darkening to a dirty brown with age. The thin layer of flesh is grey-brown in the cap, while lighter in the stem. It has ochre-cream (later darkening to rusty-ochre) gills, which are adnate, leaving a brown spore print. The spores themselves are elliptic to oval, measuring between 10–20 µm by 6–12 µm. It has two-spored

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-c ...

, and a cellular

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 ...

. It is generally a little larger than the slightly more common coprophilious '' C. pubescens'', while it can be differentiated from other dung-loving ''Conocybe'' by its two-spored basidia, large spores and the fact it does not have lecythiform (flask-shaped)

caulocystidia A cystidium (plural cystidia) is a relatively large cell found on the sporocarp of a basidiomycete Basidiomycota () is one of two large divisions that, together with the Ascomycota, constitute the subkingdom Dikarya (often referred to as t ...

Edibility

British mycologist Roger Phillips lists the edibility as unknown, while

David Pegler David Norman Pegler (born 2 November 1938) is a British mycologist. Until his retirement in 1998, he served as the Head of Mycology and assistant keeper of the herbarium at the Royal Botanic Gardens in Kew. Pegler received his BSc from London Univ ...

considers it inedible. The flesh has no distinct smell or taste.

Distribution and habitat

''Conocybe rickenii'' grows on extremely rich soil, especially on dung and

compost heap Compost is a mixture of ingredients used as plant fertilizer and to improve soil's physical, chemical and biological properties. It is commonly prepared by decomposing plant, food waste, recycling organic materials and manure. The resulting m ...

s. It can be found in very large numbers in gardens where horse manure has been used to enrich the soil. It can be found in Europe, Australia, and

Pacific islands Collectively called the Pacific Islands, the islands in the Pacific Ocean are further categorized into three major island groups: Melanesia, Micronesia, and Polynesia. Depending on the context, the term ''Pacific Islands'' may refer to one of se ...

and the United States.

References

{{Taxonbar, from=Q5162125 Bolbitiaceae Fungi described in 1930 Fungi of Europe Fungi of Oceania Fungi of North America Fungi without expected TNC conservation status