Grey Fork-winged Twist-tail Cheilotrichia cinerascens

I keyed this using Stubbs. At first I wasn't wholly convinced the vein R2 was exactly as described and, as I looked at it lying on its back under the microscope, it looked more yellowy than the text suggested this species should be. However keying forwards past cinerascens led to a dead-end so I flattened the wing under a microscope slide to get a more accurate view of the shape. This put my mind at ease, and a closer look at the body revealed that greyish-brown was just about a fair description. The top of the thorax was clearly grey (slightly brown) though the lower thorax was more yellowy, especially at the rear, but even here there was a fair bit of grey shading on the pleura.

female Grey Fork-winged Twist-tail Cheilotrichia cinerascens showing wing, Wendling Beck Environment Project (Norfolk, UK), 8th October 2023

I keyed this using Stubbs too. My challenge with this one was in interpreting the tibial spurs (or as I now realise, not spurs). The tibia had spines (I think) which I initially took to be spurs, and so keyed past Cheilotrichia and eventually landed in a dead-end. Once I figured out my mistake it was easy.

female Grey Fork-winged Twist-tail Cheilotrichia cinerascens showing wing and apex of tibia, Wendling Beck Environment Project (Norfolk, UK), 19th March 2024