Southbya tophacea Green Blackwort

A dioicous, strongly calcicole species which grows in moist calcareous habitats, particularly on dripping tufa on coastal limestone cliffs, but also on calcareous walls and dunes. This is a small leafy liverwort which forms dense patches with rounded, opposite leaves that are connected across the stem. It is a rare, Medterranean-Atlantic species in Britain with just a handful of sites on the west coast between Cornwall and north Wales. It has been known from coastal tufa formations in East Glamorgan since the 1960s and was discovered by Des Callaghan in the Mewslade Valley in West Glamorgan in 2017. Sporophyte capsules are occasional.