Yorkshire Status: Local resident.

Plain Clay has always been a local and rather enigmatic species. In 1883 Porritt called it "very local" and listed Doncaster, Richmond, Leyburn and Scarborough as sites where it was found. In 1970 Rutherford could only add Middlesborough and Pickering as sites. Sutton and Beaumont in 1989 were under the impression that is was moving south which seems an odd comment.

The current situation is that is is resident in a broad band from Harrogate in the south to Richmond in the north, and as far west as mid-Wensleydale, and recently there have been records from upper Teesdale, suggesting that climatic change is pushing it further north. It seems to have disappeared from VC62 over 30 years ago. Nationally it used to occur in Wales and south-west England, but it seems to be well on its way to extinction in these areas. The only other healthy populations seem to be in south-east Scotland and in the Scottish Highlands. In its core area, it can be fairly common. It is happiest in open broad-leaved woodland, but often comes into gardens. There has been a slight fall in numbers in recent years, and big counts seem to be less common, the maximum being 42 at High Batts NR on 8/8/2003.

Sutton & Beaumont, 1989: This species has extended its range southwards since the last list (YNU, 1970). Taken in north VC62 in 1967, it was later found to be well established in VC65 and has now spread to the north of VC64 as well.

	Retained Specimen / Photograph will be Required.

Recorded in 36 (18%) of 200 10k Squares.
First Recorded in 1845.
Last Recorded in 2023.
Additional Stats