Any ideas as to this Iris?

Growing in Trelissick Gardens, Cornwall.
Looks like a yellow flag iris but with gorgeous brown markings.




TIA
Fof

 

Definitely not yellow flag iris.
Had a look on the internet and what about Iris psuodacorus 'Roy Davidson'.

 

Hi, On the Levels.
Now I am even more confused - not difficult to confuse me though.
I know Iris pseudacornis, as the yellow flag iris or water iris that grows in and around lakes and ponds.
This is not growing any where near standing water, but in an herbaceous border. That is a Hydrangea directly behind it
I must admit, though, that it does look similar to 'Roy Davidson', as well as 'Berliner Tiger'.

 

From my experience, Flag iris will grow in any soil which is poor draining so has a good moisture content