This rust is extremely rare in Europe, China (?), Turkey and Morrocco.
This is a national Biodiversity Action Plan species for GB and is listed as Critically Endangered D by Evans et al. (2006). It appears to be frequent on the relatively large populations of viper’s-grass Scorzonera humilis on a single site in Glamorgan though has not been found recently at the two other known sites for the host in Dorset.
Cheffings et al. (2005) list the host plant as a British national RDB Vulnerable species as it is in Wales (Dines 2008). This rust is entirely dependent on this single host species and the Welsh population is at the very edge of the European range of the rust. One Dorset host population is believed to be at risk from sea level rise and management of the other site may well have been sub-optimal in the recent past.
The Glamorgan population is protected to some extent by a SSSI designation. Given that the future of this rust is dependent on the management of a single site it is considered to be Critically Endangered D1 in Wales as well as in Britain.
[Woods, pers. com.]
Preliminary evaluation: DD.
There are few reports and very few specimens.
Population Trend: Uncertain
Parasitic on Scorzonera sp., possibly other Asteraceae - not uncommon host plants; there may be problems with host plant identification, and the rust is perhaps under-recorded.
In UK one population is proteceted by SSSI designation - but not for the fungus. There could be managament issues.
This species needs to be further investigated.
Farr, D.F., & Rossman, A.Y. Fungal Databases, Systematic Mycology and Microbiology Laboratory, ARS, USDA. Retrieved March 6, 2015, from http://nt.ars-grin.gov/fungaldatabases/
Evans, S., Henrici, A., & Ing, B. (2006). The Red Data List of Threatened British Fungi. BMS [WWW document] URL http://www. britmycolsoc. org. uk/index. php/download_file/view/528/[accessed 6 June 2013].