Redlead roundhead mushrooms are bright red and, when damp as here, a cap which is slightly glutinous. The vivid colour, shape and glutinousness are hints that they may be related to the verdigris species featured a couple of days ago. It is indeed in the same genus.
Verdigris mushrooms are northern hemisphere fungi: from Europe, parts of Asia and of north America. Redlead roundheads originate in Australia. They were first recorded in Britain in the last century, almost certainly arriving on imported timber. Now quite common, but still most often found growing on wood chip mulch.