Taxon distribution as listed in assessment
Within the UAE, this species is confirmed from a single site (small rocky pools at the base of the waterfall and adjacent rocks) in Wadi Wurayah (first reported by V. Chalmers in 2009 (Feulner 2016); <a href=""http://data.rbge.org.uk/herb/E00647674"">RBG Edinburgh Herbarium</a> specimen collected 2013). The species was also recorded by Gallacher from the Dubai Desert Conservation Reserve, however this area represents a very different habitat and altitude, and the record requires confirmation. On a global scale, the species is native to temperate Eurasia, the Americas, North Africa, Australia and to the southwest Pacific (Board of Trustees, RBG Kew 2018). In the Arabian Peninsula, this species is also known from scattered localities in Saudi Arabia (Chaudhary 2001) and from isolated springs and waterbodies in Oman (Patzelt 2014) and on Socotra (Miller and Morris 2004). The nearest confirmed locality to Wadi Wurayah is at the Jazirah oasis in Oman (Jongbloed et al. 2003, Feulner 2016), more than 100 km away.
History
The species was not recorded in the UAE in 1996 but it is possible that the species was present either in the seedbank or as underground rhizomes or, alternatively, it was simply not found or identified in surveys. We consider that it is likely to have been present but in similarly small numbers, or as propagules, and would have qualified as CR in 1996.