A while back I asked about the correct taxonomic name for the rust on Tutsan and it’s allies (Melampsora hypericorum sensu auct Brit), and promised to raise more questions in another thread: this is Most originate either directly from the treatment in Julia Kruse’s 2019 book Faszinierende Pflanzenpilze, or from a slightly earlier monograph on German rusts. There are a number of differences in treatment both from classic literature for Britain Ireland (Ellis & Ellis, British Rust Fungi etc), and where I have checked with Roesten van Nederland.
A couple of queries for starters:
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[*]Is Puccinia petastis-pendulae a British or Irish taxon? The aecial stage on Colt’s-foot appears to be macroscopically, and indeed microscopically, very similar to Puccinia poarum. There are no records in Cate-2 nor on GBIF for Britain and Ireland (and I can’t remember m password for FRDBI).
[*]It’s been suggested that Burnet Rose Rosa spinosissima is the host of quite a few other Phragmidium spp. other than Phragmidium rosae-pimpinellifoliae. I think JennyS’ example of the latter is on Rosa multiflora. From memory FRDBI has about 80 records on this host, of which 1-2 are not P. rosae-pimpinellifoliae. CATE-2 has 51 records for this taxon of which 18 have Burnet Rose as the host (most under the invalid name Rosa pimpinellifolia
). I think Chris only had a few records for Yorkshire (back in 2012ish). My experience in Northern Ireland is that Burnet Rose suckers can be spotted because they already have the rust. I’d be surprised if P. rosae-pimpinellifoliae is not ubiquitous along the Causeway Coast and dune systems on the Mulligan. I forgot to look out for it when I was in Donegal. I think this is also true in places in Lancs and Cheshire (Red Rocks at Hoylake). I presume all Phragmidium are awkward customers as aecia, so the records may not have been determined through microscopy.
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I’ll add more questions to this list as they crop up from reviewing records which have come into the Plant Galls of Britain & Ireland project on iNaturalist (which I set up early in the first lock down). This captures all observations on iNaturalist of rusts, smuts and Taphrina in both countries.