I've found exactly one of these, dead, on my kitchen floor most mornings this past week.
It looks like a large flea, is about 1 cm long (picture compares it to a British 10 pence coin, approx. 24.5 mm in diameter) and 2 mm thick with a laterally flattened body.
I believe it to be of the order Siphonaptera, but am unsure as to what exactly it is.
Can anybody identify the exact species of this arthropod?
If it helps, I live in the South-West of the UK.