Protomyces macrosporus Unger, 1834
on Apiaceae

Aegopodium podagraria, Bilthoven © Arnold Grosscurt

underside
Heracleum sphondylium, Zeewolde, Harderbos © Hans Jonkman

Anthriscus sylvestris, Nieuwendam: small warts on the leaves, swelling and torsion of the stems

Aegopodium podagraria, Castricum: the ascogenous cells are embedded in the swollen tissue without a recognisable structure

Aegopodium podagraria, Belgium, prov. Antwerp, Meerhout, de Vloyen © Carina Van Steenwinkel: early winter

ascogenous cells
gall
elliptic swellings of the veins and stems. Embedded in the host tissue dense groups of thick-walled spores, or better ascogenous cells.
host plants
Apiaceae, oligophagous
Aegopodium podagraria; Ammi majus; Angelica archangelica, sylvestris; Anthriscus caucalis, sylvestris; Athamanta cretensis; Berula erecta; Carum carvi; Chaerophyllum hirsutum, villarsii; Cicuta virosa; Conopodium majus; Coriandrum sativum; Daucus carota; Heracleum sphondylium & subsp. pyrenaicum; Laserpitium halleri, latifolium, peucedanoides; Ligusticum mutellina, mutellinoides; Meum athamanticum; Myrrhis odorata; Oenanthe crocata, fistulosa; Pastinaca sativa; Peucedanum cervaria, ostruthium, palustre; Pimpinella major, saxifraga; Selinum carvifolia; Seseli libanotis, montanum; Sium latifolium; Torilis japonica; Trinia glauca.
references
Bacigálová (2004a), Bacigálová, Mułenko & Wołczańska (2005a, 2008a), Blumer (1946a), Brandenburger (1985a: 425), Buhr (1964b, 1965a), Chinery (2011a), Coulianos & Holmåsen (1991a), Dauphin & Aniotsbehere (1997a), Doppelbaur & Doppelbaur (1973a), Ellis & Ellis (1997a), Gjaerum (1976a), Ivimey-Cook (1988a), Jage, Klenke, Kruse ao (2016a), Jage, Scholler & Klenke (2010a), Klenke & Scholler (2015a), Kozłowska, Mułenko & Heluta (2015a), Kruse (2019a), Mułenko, Sałata & Wołczańska (1995a), Negrean (1996b), Preece & Hick (2001a), Reddy & Kramer (1975a), Redfern & Shirley (2011a), Roskam (2009a, 2019a), Scheuer & Bechter (2012a), Scholler, Reinhard & Schubert (1996a), Tomasi (2014a).