Tuberculatus (Tuberculoides) borealis (Krzywiec, 1971)

Morphological characters

1.9-2.3 mm.
Greenish blue to yellow aphid marbled with green.
Larva and nymph: antenna dark brown at segmental sutures, capitate hairs present on abdomen, cornicles short, cauda rounded and anal patch complete.
Alate: antenna same length as body, ringed at segmental sutures and with processus terminalis very short, abdomen with four pairs of tubercles spread on segments I-IV, the 4^th pair being the smallest, cornicles straight, short and light-colored (or very slightly pigmented) at tip, cauda knobbed and anal patch bilobed.

See identification file

Life cycles

Monoecious holocyclic.

Host plants

Quercus spp and more particularly Quercus robur, pedunculate oak

Particular characteristics

Tuberculatus borealis colonizes the underside of leaves of pedunculate oak. As it lives on the same host as T. annulatus, it can easily be confused with that highly common species.
The individuals form small scattered colonies. The sexual forms appear in the autumn.