''Marasmius sasicola'' is a species of Marasmiaceae fungus known from Kanagawa Prefecture, Japan. First collected in 2000, it was described in 2002 by Haruki Takahashi. The species produces small mushrooms with white caps and very short, very thin black stems. Unlike in other, similar species, the stems enter the plant matter on which the mushroom grows. The six to eight white gills are spread out around the cap, and all of them reach the stem. The flesh has no taste or odour. Found in June, the species grows on dead ''

Sasa Sasa may refer to: People * Saša, a given name * Genjū Sasa (1900–1959), Japanese film director and critic * Sa'sa'a bin Sohan (598–666), a companion of Imam Ali revered by Shia Muslims * Sasa (politician), special envoy to the United Nation ...

'' leaves, from which it takes its

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

Taxonomy and naming

''Marasmius sasicola'' was first described by Haruki Takahashi (2002) in an article in ''

Mycoscience ''Mycoscience'' is a peer-reviewed scientific journal covering all aspects of basic and applied research on fungi, including lichens, yeasts, oomycetes, and slime moulds. It is the official journal of the Mycological Society of Japan. A publica ...

'', based on specimens collected from Ikuta Ryokuchi Park, Kawasaki, Kanagawa Prefecture, Japan in 2000 and 2001. The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

''sasicola'' refers to the fact the species grows upon the leaves of ''

'' species. The Japanese

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 ...

for the species is ''Sasa-no-houraitake''. Within the genus '' Mycena'', it probably belongs to the section ''Marasmius'', and the subsection ''Penicillati'', due to characters of 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 ...

, gills and

pileipellis The pileipellis is the uppermost layer of hyphae in the pileus of a fungal fruit body In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowe ...

(the outer-most layer of the cap).

Description

''Marasmius sasicola'' produces mushrooms that have convex caps from in diameter featuring folds or striations. The caps do not expand or flatten with age, and are dry and dull. The cap surface is covered in tiny grains which vanish as the mushrooms age. The caps of young mushrooms are coloured light brown, but paler at the cap margin; as they mature, the caps become paler, approaching white when fully matured. The very thin, smooth

measures between in length by thick. It connects to the centre of the cap, and is a dark brown to black colour. Mycelial cords cannot be seen at the base of the stem, which anchors itself into the

substrate Substrate may refer to: Physical layers *Substrate (biology), the natural environment in which an organism lives, or the surface or medium on which an organism grows or is attached ** Substrate (locomotion), the surface over which an organism lo ...

. The white gills can be adnexed (attaching to the stem by only part of their depth) to adnate (attaching by their full depth). They are not at all crowded, with between 6 and 8 separate gills, all of which reach the stem. Each gill is up to broad, though it is thinner at the edge. The mushrooms have a very thin layer of whitish flesh up to thick. The tough but flexible flesh lacks any odour or taste.

Microscopic characteristics

''Marasmius sasicola'' produces colourless, ellipsoid

basidiospores 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 pro ...

of between 8 and 10 by 4 to 6 micrometres (μm). The spores have no ornamentation, are not amyloid and have thin

cell wall A cell wall is a structural layer surrounding some types of cells, just outside the cell membrane. It can be tough, flexible, and sometimes rigid. It provides the cell with both structural support and protection, and also acts as a filtering mech ...

s. In his examinations, Takahashi did not observe any basidia, but he did describe the club-shaped basidioles (immature basidia) which measured from 18 to 26 by 6 to 10 μm. The tightly packed cheilocystidia ( cystidia on the edge of the gill) form a sterile edge to the gill, and there are no pleurocystidia (cystidia on the face of the gill). The

, the top layer of the cap, forms a hymeniderm, a cell structure reminiscent of the

hymenium The hymenium is the tissue layer on the hymenophore of a fungal fruiting body where the cells develop into basidia or asci, which produce spores. In some species all of the cells of the hymenium develop into basidia or asci, while in others some ...

on the gills. This is made up of club-shaped cells measuring between 2 and 8 by 7 to 10 μm, with reddish-brown, smooth cell walls up to 1 μm thick. The stipitipellis, the outermost layer of the stem, is made up of cylindrical hyphae measuring from 3 to 6 μm in width, which run parallel to one another. They have featureless brown cell walls measuring up to 1 μm thick, and the septa (the walls separating individual cells) have clamp connections. The flesh in the cap is made up of irregularly arranged cylindrical

hyphae 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 ...

from 5 to 15 μm wide. They stain a dark reddish-brown in Melzer's reagent or

Lugol's solution Lugol's iodine, also known as aqueous iodine and strong iodine solution, is a solution of potassium iodide with iodine in water. It is a medication and disinfectant used for a number of purposes. Taken by mouth it is used to treat thyrotoxicosi ...

. The flesh in the stem is made up of hyphae which run down the stem and measure 4 to 11 μm in thickness. The smooth cell walls are colorless, but again stain a dark reddish-brown in Melzer's reagent or Lugol's solution. The septa have clamp connections.

Similar species

'' Marasmius subconiatus'', known from Sri Lanka and Indonesia, is somewhat similar to ''M. sasicola''. It can be differentiated as its stem does not enter the substrate, and the gills differ. In ''M. subconiatus'', the gills are orange, and sport cheilocystidia which are pale yellow.

Habitat and distribution

''Marasmius sasicola'' is known from the lowland forests of Kanagawa Prefecture, Japan, and can be found in June. Mushrooms grow in large numbers close together, and grow from dead leaves of ''

'' (grass bamboo) which have fallen.

References

External links

Agaricales of Southwestern Japan
Images of holotype specimen {{Taxonbar, from=Q6754917 sasicola Fungi of Asia Fungi described in 2002