I picked up a sample of Campylopus from humus under conifers near Ystradgynlais last week. In the sample were two tiny plants which were unfamiliar - I don't have photos of the whole plant but the leaf below looks distinctive enough, I just can't work out what it is. At first I thought it might be an Entosthodon but the cells are too small. I considered Tortula, but do any of them have such strongly toothed leaves? I'm sure I'm just missing something obvious. Any suggestions welcome, thanks.
The leaf below is just under 2mm long. Mid leaf cells approx. 15-20 microns diameter. Associates were C. pyriformis and Calypogeia fissa.