Today's lunchtime outing with Alfie was to another spoil site just up the road at Grovesend (SN597007). There were no odd-looking Fissidens, but the odd-looking Didymodon I reported last November (see here), growing on concrete bases not far from this site, was again locally abundant. The 'scope pic shows it alongside fallax and note the adaxial costal cells are predominantly square. The substrate this time was seasonally inundated, fine black spoil - other species present where it occurred would suggest mildly basic conditions. I think previously we cautiously concluded rigidulus provided the best fit, though the outcome was not completely satisfactory. I'll send a sample to Sam to see if can pin it down, but opinions are always welcome. The only other oddities were Homalothecium lutescens growing as an epiphyte on a Hawthorn trunk and what looked like a sterile, flat-leaved Weissia with the same habit as controversa var. densifolia? Other general interest was provided by male plants of Didymodon fallax(photo below) and some nice fruiting patches of Cephaloziella divaricata (bottom photo).