The bright yellow images show the slime mould, or plasmodium stage.  When they mature they become dry and turn brown then grey and produce blackish spores. They have a very brittle outer wall that cracks and fractures into angular pieces.

Pine needles, logs, stumps, debris or sometimes they climb living plants.

Autumn.

Widespread and fairly frequent in Britain.

Uncommon or under-recorded in Leicestershire and Rutland.