Unidentified plant

Unidentified plant

Observation - Unidentified plant - UK and Ireland. Description: Does anyone know what this might be? It keyed out as a buttercup but the leaf shape doesn't quite match the picture in my flower guide! Found in damp grassland.

Does anyone know what this might be? It keyed out as a buttercup but the leaf shape doesn't quite match the picture in my flower guide!

Found in damp grassland.