A small erect slime mould, often found in large colonies, deep red, but fading with age, crowded or gregarious, 1 or 2 mm total height.

There are three species of Acyria with red/pink sporangia (A. minuta, A. insignis and A. denudata), which need microscopy for definite identification. 

On dead wood.

Autumn.

Widespread and fairly frequent in Britain.

Occasional in Leicestershire and Rutland.