Uromyces silphii Arthur, 1907
on Silphium
gall
Aecia yellow, cupulate, on discoloured spots at the underside of the leaves.
spermogonia, aecia
Asteraceae, monophagous
Silphium perfoliatum.
on Juncus
Juncus tenuis, Belgium, prov. Antwerp, Retie, Witte Netevallei, 29.viii.2020 © Carina Van Steenwinkel
uredinia
telia
urediniospore
urediniospore
teliospores
teliospore with pedicel
gall
Uredinia and telia amphigenous, light and dark brown, respectively. Urediniospores with two pores above the equator. Teliospores one-celled, smooth, wall apically strongly thickened; pedicel at least as long as the spore (up to 35 µm), often deciduous.
uredinia, telia
Juncaceae, narrowly monophagous
Juncus tenuis.
notes
This North American species was first discovered in Central Europe in 1956. The occurrence on Silphium seems not yet to be confirmed in Europe.
references
Beenken & Senn-Irlet (2016a), Brandenburger (1985a), Dietrich (2013a), Gäumann (1959a) Jage, Kruse, Kummer ao (2013a), Klenke & Scholler (2015a), Kruse (2014a, 2019a), Melzer, Pittoni, Poelt & Scheuer (1984a), Mułenko, Piątek, Wołczańska ao (2010a), Poelt & Zwetko (1997a), Termorshuizen & Swertz (2011a), Woods, Stringer, Evans & Chater (2015a).