The rust Melampsora epitea sensu lato produces aecia on the underside of various hosts, including spindle (Euonymus), silver-fir (Abies), larch (Larix), orchids (Orchidaceae) and currants (Ribes).    On Spindle and orchids it is considered to be gall-causing, but not on the other aecial hosts.

The primary host, bearing uredinia and telia, is a Salix species; it is not a gall-causer on this host.

This is a probably a complex of species, and the taxonomy is not clear, so we are treating this species as 'sensu lato' - in a broad sense.  Some authors separate these into different species, depending on the host; see Further Information below.

Other Melampsora produce uredinia and telia on their primary hosts, Salix species.  Ribes and Larix are also the aecial hosts of other species of Melampsora.

host/microscopy

Photograph the rust on the host.  Ensure you have noted the host-plant species in your comments.  Microscopic examination will be needed for some aecial host species, and for all Salix uredinial/telial hosts.

Alternating between various species in the aecial stage (e.g. Ribes, Larix, Abies, Euonymus) and Salix species in uredinial/telial stages

On Plant Parasites of Europe website, taxonomy is different to the NBN.  Here, Melampsora epitea is treated as a complex of species, including the following that may be present in VC55.  It is not clear how these correspond to NBN taxonomy.

• Melampsora abietis-caprearum - aecial host = Abies
• Melampsora euonymi-caprearum - aecial host = Euonymus (NB. this appears to be synonymous with M epitea var. epitea).
• Melampsora laricis-epitea - aecial host = Larix
• Melampsora repentis - aecial host = various species in Orchidaceae
• Melampsora ribesii-epitea - aecial host = Ribes
• Melampsora ribesii-purpureae - aecial host = Ribes
• Melampsora ribesii-viminalis - aecial host = Ribes