T. trifolii

Therioaphis trifolii (Monell, 1882)

Yellow clover aphid

blanc 192x128

1.4-2.0 mm.
Apterous: whitish to yellowish with small abdominal patches more or less dark topped with a hair and a knobbed cauda, weakly pigmented on a bilobed anal plate.
Alate: abdomen light-coloured with a network of small patches, ends of wing veins smudged, cornicles very short, slightly pigmented, cauda knobbed, slightly pigmented on a bilobed anal plate.

Monoecious holocyclic in regions with climate cold.
Anholocyclic in the other regions.

Fabaceae: Medicago (lucerne), Trifolium (clover), Melilotus (melilot), Onobrychis (sainfoin), Lotus (birdsfoot trefoil).

T. trifolii is not frequent in France.

Injections by T. trifolii lead to drying and shriveling of leaves.
The secretion of honeydew leads to formation of sooty mould which diminishes chlorophyll uptake.
It transmits lucerne mosaic virus (AMV) according to the non-persistent mode.

Ennemis naturels



  • Aphelinus asychis
  • Praon exoletum
  • Trioxys complanatus

Modification date : 07 February 2023 | Publication date : 08 November 2010 | Redactor : Evelyne Turpeau, Maurice Hullé, Bernard Chaubet