Macrofossils of late Precambrian (Neoproterozoic) age have been known only during the last sixty years, following their discovery in Australia and South Africa. Within this period, numerous other occurrences of fossils of a similar age have been documented, with the first from Britain being discovered in Charnwood Forest, Leicestershire, in 1957. All these ancient biotas are dominated by medusoid-like forms, associated with a suite of other fossils, but all are quite unlike those found in succeeding Cambrian strata. They are interpreted as soft-bodied organisms which have fossilized in rather unusual circumstances. The fauna as a whole is referred to as the Ediacaran, taking its name form the Ediacara Hills, South Australia, which is where the first and most diverse of these faunas was discovered.
The second discovery of Ediacaran fossils in Britain came in 1977, when tuffs exposed in a small quarry near Llangynog, Carmarthenshire, yielded significant numbers of medusoid-like fossils, together with a distinctive trace fossil. They are of a similar age to those from Charnwood Forest, but the composition of the fauna differs in detail. It is now being described systematically for the first time.