The fruitbody is a mushroom, with a cap atop a central stem. The smooth, dry cap is up to 5 centimetres in diameter (though often no more than about 3) and dirty cream to buff or pale brown. It is convex (but may flatten with age) and there is a distinct central hump (technically an umbo). The gills are creamy to buff and more widely spaced than in most mushrooms. The stem may grow to several centimetres long by about half a centimete wide and is of a similar colour to that of the cap. It is tough and pliable.
There is neither a universal nor a partial veil.
Spore print: white.
The mushrooms appear on the ground, often in large groups or fairy rings, and they can appear fairly quickly after rain, even in summer. Favoured habitats are open areas such as lawns, parks, sports ovals, nature strips and pastures.
It may have been introduced to Australia.
Look-alikes
There are many small, creamy/brownish, mushrooms - though not so many in the open habitats noted above. In such a habitat, Marasmius oreades is fairly distinctive.
Marasmius oreades is listed in the following regions:
Canberra & Southern Tablelands | South Coast