Euastrum gayanum

Range & Status

This potential Red List desmid is an Endangered IUCN (1994), Nationally Rare species, and has been recorded at Lower Bostraze bog, near St. Just in West Penwith (SW392321). This area consists of a series of pools formed by old extraction pits filling with water from the surrounding moorland and has been identified as the most important desmid site on the south-west peninsula of Britain. This site, and many others, were sampled by John Ralfs, one of the most influential desmid specialists of his time in the middle part of the 19th century. More recently, in 1983 and 1993, it has been re-surveyed by David Williamson. The Lower Bostraze site is nominated as a European/Internationally Important Plant Area (IPA) for desmids (Brodie et al ., 2007). It has been chosen due to its species richness (100 species recorded), its long history of study and for the fact that it is a threatened priority habitat. Lower Bostraze has been designated as a County Wildlife Site (CWS).