Just very briefly...
The weeverfish (AKA trachinus vipera) is found in shallow waters around the coast of the UK.
It is small and sandy-coloured, with sharp dorsal spines.
If you are unfortunate enough to stand on it you will get intense pain.
Happily the toxin produced by the weeverfish is denatured above 40C - so dunk the foot in hot water and the pain should stop.
On that most random of MRCP revision notes, lets end for the day!