Plant Parasites of Europe

leafminers, galls and fungi

gallers on Minuartia

Dichotomous table for gallers on Minuartia

(incl. Honckenya. ‒ Comp. Arenaria, Stellaria)

by Hans Roskam

1a On stems and leaves => 3

1b On flowers => 2

2a Flowers ± swollen globularly, unopened. Inner organs soon destroyed and replaced by spore balls consisting of a yellowish-brown powdery dust. Arenaria pungens; Minuartia hybrida: Thecaphora saponariae s.l.

2b Flowers outwardly not conspicuously changed; anthers shortened and swollen; later on filled with a dusty violet spore powder. M. recurva: Microbotryum violaceum

3a Malformations caused by fungi fruiting at surface => 5

3b Malformations caused by animals => 4

4a Leaves on slightly stunted shoots more densely arranged, the leaf blades a little deflected over their tip, curved upwards at margin. Honckenia peploides: Myzus certus

4b Shoot axis stunted, bent at infestation site. Leaves more clustered, leaf blades distorted. Honckenia peploides: Philaenus spumarius

5a Leaves or stem with rotund- oblong-oval, yellowish brown pads, occasionally slightly bent, protruding on underside, soon bearing a brown sorus at surface. Arenaria montana, retusa, serpyllifolia, tenuifolia; Minuartia hybrida, laricifolia, verna: Puccinia arenariae

5b Systemic diseased shoots growing rigidly erect; leaves reduced, slightly thickened and ± bent, spoon-like. On leaf underside and stem grey down of conidiophores develop. Honckenia peploides: Peronospora honckenyae

5c Bushy accumulation on twisted and thickened stems; capsules inflated. M. viscosa: Inducer unknown

Last modified 28.v.2020