On Malva sylvestris, no idea what it might be, it reminds me of a bright orange vein-gall I've seen on meadowsweet...
Caution: Do NOT use iSpot to identify fungi to eat!
Some fungi are very poisonous so a mistaken ID could have serious consequences.
No interactions present.
Lat/Lng: 51.0153, -3.1068
OS grid ref: ST224245
Beside River Tone