Plant Parasites of Europe

leafminers, galls and fungi

gallers on Nepeta

Dichotomous table for gallers on Nepeta

by Hans Roskam

1a On parts above ground => 2

1b Roots with nodular swellings. N. cataria: Meloidogyne hapla

2a On flowers or fruits => 6

2b On vegetative organs => 3

3a On leaves => 5

3b On shoot tips or axial parts => 4

4a Tip of shoot ± disfigured. Youngest leaves erect, folded together, yellowish with cartilaginously rolled margin. Containing orange-yellow larvae. N. cataria: Wachtliella stachydis

= Midge described from Stachys, on which it also induces inflorescence galls. Identity of the midge on Nepeta is doubtful

4b Shoot axis with multi-chambered, elongate and bulging swellings, up to 30 mm long. In each chamber is a single, curved, lemon-yellow beetle larva. N. cataria: Squamapion vicinum

5a Leaves curled or loosely rolled. N. cataria, nepetella & subsp. aragonensis, nuda: Aphis nepetae

5b Leaves folded or rolled. N. cataria: Aulacorthum solani

6a Gall on flowers => 7

6b One mericarp transformed into a ± globular gall, up to 5 mm long, the three remaining ones aborted. Calyx enlarged, cup- or bell-shaped, later on rupturing over its length. Corolla atrophied. Containing a single larva. N. nuda, also N. beltranii, cataria, grandiflora, latifolia, nuda & subsp. albiflora, ucranica & subsp. parviflora: Liposthenes kerneri

7a Flowers swollen at base, disfigured, often unopened. Containing red larvae. N. cataria: Jaapiella catariae

7b Flower buds swollen, egg-shaped, dark-green, unopened. N. nuda: Asphondylia sp.

Last modified 17.v.2020