In general, Marasmius fruit bodies are small mushrooms (with a stem centrally positioned under the cap) that are found growing amongst twig and leaf litter in forests, woodlands, city parks or suburban gardens.
The caps are often between 1 and 2 centimetres in diameter, and no more than a few millimetres thick. The caps come in a range of colours. The gills are commonly white. The stems are commonly 1 or 2 millimetres in diameter but may grow to 2 or 3 centimetres in length. Some commonly seen species have black stems, looking very much like thick, black hairs but other coloured stems occur in the genus.
Neither a universal nor a partial veil is present.
Spore print: white.
The fruit bodies often appear in large numbers.
Look-alikes
Mycena is another genus (with many species known in Australia) in which the fruit bodies are small, litter-inhabiting mushrooms that are (1) common and (2) found in the same habitats in which you find Marasmius. Hemimycena and Delicatula are two other genera that are look-alike candidates.
Identification of Marasmius on Canberra Nature Map
In many cases, the reliable identification of a mushroom as a species of Marasmius is impossible without the study of a specimen. A photograph won’t suffice, though it might be suggestive. Whenever Marasmius is a very plausible suggestion for a sighting, almost invariably there would still be a question mark hanging over the identification.
It is for that reason that Marasmius? will be given as the genus, as an immediate reminder of the uncertainty attached to the identification.