Microbryum floerkeanum

This small species was new to Pembrokeshire when found on limestone tracks at Castlemartin Range a couple of years ago. It was more surprising to find it in two places near St David's last week. The first was on a long-stored soil and stone pile on an old runway on St David's airfield, where it was accompanied by Microbryum rectum and the rather similar but larger Tortula acaulon. The piles here may contain mixtures of old building stone and lime mortar, which would explain the presence of these calcicoles.

Microbryum floerkeanum location on St David's airfield

No such calcareous influence is evident at the second location, a cereal stubble field near the coast at Llanunwas. It was in tiny quantity here alongside more mundane species such as Bryum violaceum, Tortula truncata and Riccia sorocarpa. It is known as a stubble field species in England, although usually on fields over chalk or limestone. I wonder if it's overlooked in other such habitats in south Wales - it would not be found if not fruiting, and is clearly easy to miss even when it is.

Microbryum floerkeanum location at Llanunwas

One other interesting calcicole was found on the edge of the shingle-dressed driveway at Llanunwas - Tortula protobryoides. Several fruiting patches represent the first county record away from the south coast limestone and dune systems.

Tortula protobryoides and location, Llanunwas