Plant Parasites of Europe

leafminers, galls and fungi

gallers on genus Molinia

Dichotomous table for gallers on Molinia caerulea

by Hans Roskam

1a On vegetative plant parts => 3

1b In inflorescences or single flowers => 2

2a On inflorescence stalks or spikes. Inflorescence partially ± severely stunted and greened or bleached. Aceria tenuis

2b Single ovaries of a panicle strongly swollen and transformed into an oval or oblong smut body, up to 10 mm long; inside develop brown-black spore masses, at first clotted, later on crumbling and forming dust of spores. Neovossia moliniae

3a On above-ground parts => 4

3b Root hairs distinctly swollen; inducer inside the hair. Sorosphaerula radicalis

4a On culms => 5

4b Leaf sheath at base swollen, bellied out. Containing a large, whitish larva, almost 5 mm long. Unidentified gall midge

5a Culm with spindle-shaped or bellied swelling => 6

5b Shoot axis immediately above the ground below the leaf sheath with weak, slightly rimmed depression. Containing a single white larva. Mayetiola moliniae

6a Culm just above the ground swollen to bellied out, apically conically narrowed gall up to 10 mm long, which erupts from the leaf sheath. Larvae white, gregarious. Mayetiola ventricola

6b Culm weakly swollen, containing a single, orange-yellow larva almost 5 mm long. cf. Lasioptera moliniae

Last modified 18.xi.2023