Can anyone help me identify this fern?
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Were there bristles at the tips of the leaflets, Dryopteris leaflets don't have them.
... Oreopteris limbosperma. This can be distinguished from the commoner Dryopteris filix-mas by the former's marginal sori, but is otherwise easy (for non-experts, such as myself) to overlook as the latter; the one time I found Oreopteris limbosperma it was growing with Dryopteris filix-mas and several other species, so it was easier to see a difference.
It's not Athyrium or Polystichum.
Lat/Lng: 53.7381, -2.0361
OS grid ref: SD977268