Another pond blip:

This was transferred from a neighbours pond earlier in the year, I think it's Ranunculus Lingua - Greater Spearwort, happy
to be corrected.

From the Internet:
This plant has several names, ‘Greater Spearwort’ and ‘Water Spearwort’.  This particular Rununculus is a native aquatic marginal plant that grows to a height of 60-100cm.  It has unusual lanceolate leaves and produces large yellow cup-shaped flowers in the height of the summer.  It will grow in damp soil or to a water depth of up to 30cm and looks great when colonised around natural clay bottomed ponds and lakes.