Identification file

Rhopalosiphum padi (Linnaeus, 1758)

1.5 - 2.3 mm

Apterous: dark green, olive toned, globular, with broad rust-coloured patch   (1) at the base of cornicles
Forehead: with a pronounced medial tubercle (2)
Antennae short  (3) (about half the length of body)
Cornicles cylindrical at least 2 times longer  than the cauda and marked by a constriction at tip (4)
Cauda small (5)

The photo shows, on the inner side of the abdomen of the apterous form, some oblong features with red spots: these are embryos with red eyes which will give rise to the future larvae.

Alate: dark green, olive toned, globular; abdominal pigmentation consists of circular marginal sclerites (6), post-cornicular   sclerites (7)and also two arcuate stripes behind the cornicles (8)
Forehead: with pronounced medial tubercle
Antennae short (about half length of body) consisting of 6 segments, moderately long with base of VI not swollen and processus terminalis markedly straight  (9), (difference with Rhopalosiphum insertum, see file on R. insertum)
Cornicles dark, cylindrical, at least 2 times longer than cauda and marked by a constriction at tip (10)
Cauda pigmented, small (11)

Species file