LEAF SPOTS amphigenous, subcircular to irregular, sometimes vein-limited, at first pale greyish green, later yellowish-ochraceous, pale to medium brown, finally dull greyish brown to greyish white, 1-10 mm diam, with an indefinite margin, or with a narrow to moderately wide dark border or a marginal line, sometimes with a diffuse yellowish to brownish halo.
CAESPITULI amphigenous, punctiform to subeffuse, frequently dense, greyish white, occasionally yellowish-ochraceous.
CONIDIOPHORES (cp) in small to moderately large fascicles, loose to fairly dense, sometimes confluent, forming expanded, sometimes crustose layers, originating from internal hyphae or stromata, emerging through stomata or erumpent through the cuticule, erect, subcylindric, straight to flexuous, geniculate-sinuous, simple, rarely branched, of a variable length, aseptate or septate, hyaline, smooth, 5-80(-110) x 2-6 µm.
CONIDIA (c) catenate, sometimes in branched chains, ellipsoid-ovoid, cylindrical-fusiform, hyaline, almost smooth to verruculose, 0-3-septate, (8-)10-35(-45) x 2-6 µm; ends rounded to slightly attenuated; hila slightly thickened and darkened.
PLANT HOST AND DISTRIBUTION. Ramularia heraclei affects different plant species of the genera Apium, Cicuta, Conium, Coriandrum, Hansenia, Heracleum, Levisticum, Malabaila, and Pastinaca (Apiaceae, subfam. Apioideae) growing in New Zealand, West Indies, Asia, Europe, Africa, and North America (Braun 1998).
Braun U. 1998. A monograph of Cercosporella, Ramularia and allied genera. Vol. 2. IHW-Verlag.