Plant Parasites of Europe

leafminers, galls and fungi

gallers on Lapsana

Dichotomous table for gallers on Lapsana communis

by Hans Roskam

1a On above-ground parts => 2

1b Roots with several small, spindle- to nodule-shaped swellings, bearing lateral roots. Meloidogyne hapla

2a On vegetative parts => 3

2b Florets ± stunted and greened. Unidentified gall mite

3a On leaves => 4

3b Irregular swelling in stem, up to 6 cm long by 10 mm wide; containing several chambers each with a white larva or pupa. Timaspis lampsanae

4a Galls mainly in leaf blade => 5

4b Petiole, mid- and main veins or also the leaf blades of the rosette leaves already in early spring with conspicuous, usually reddish margined or overflowed, yellowish, aecia bearing bulges. Puccinia lapsanae

5a Expanded malformations of leaves => 6

5b Leaf blades with rotund wide pads, up to 5 (7) mm, usually protruding on the underside and concave on the upper side, bearing ± deep yellow aecia. Exceptionally also spindle-shaped galls on bent leaf ridges and petioles. Puccinia opizii

6a Curvings and curlings of the leaf blade caused by aphids => 7

6b Leaf blade more or less deflected, ± bulge-like curled, dark green coloured, close to the froth-covered nymph occasionally a clustering of disfigured leaves on often one-sided stunted, bent shoots. Philaenus spumarius

7a Distinct malformations of the leaf, associated with deflected curving of the margin and curling of the leaf blade. Aphid 1.8–3 mm long, straw yellow, green or reddish; wingless adults on the dorsal side with a pattern of dark spots. Siphunculi slender, cylindrical. Nasonovia ribisnigri

7b Similar malformations. Aphid 2.5–3.5 mm long, body white. Siphunculi notably swollen, widest in the middle. Hyperomyzus lampsanae

Last modified 27.v.2020