This was the shot I was waiting for, but didn't consider quite good enough, before going off on a search for alternates yesterday, that resulted in the entry outwith the rules...
1905EPLXCN Quantock ponies by
Chris R, on Flickr
Wild ponies on the Quantock Hills, sheltering under the group of trees known as the Seven Sisters. Pentax LX, Vivitar 35-70, Superia 400
For some reason late last night I decided it wasn't "landscape" enough, so (having forgotten about the subsidiary rule that shots had to be taken in May) I went looking through the catalogue and found the February shot that I submitted. There were at least two clues that should have alerted me: the first was that when I went for a wander yesterday afternoon I checked the monthly themes on my Dropbox and saw "Mystery Month", and the second when I was wondering why so few entries! Oh well...
I had had some hopes for other shots on the same roll, taken in Holyrood Park during a 5K race as part of the Edinburgh Marathon Festival: runners, with Arthur's Seat in the background. Definitely landscape enough, but little details in the half dozen shots I took ruled them all out (yes, I know, machine gun Chris!).