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In type 2 dioecious holocyclic species, the alate gynopara, formed in the summer on the secondary host, migrate to the primary hosts. There they give birth to oviparous females. The alate males, which belong to the same generation as the gynopara, arrive in their turn on the primary hosts to mate with oviparous females. The two sexual morphs are therefore a generation apart.
When the egg hatches, the fundatrix give birth to several generations of fundatrigenia which develop on the primary host in spring. Then alate migrants leave to colonize the secondary hosts at the end of spring.

This is the case for:

• The bird cherry oat aphid: Rhopalosiphum padi which alternates between Prunus padus (H I) and a range of Poaceae (HII) 
• The black bean aphid: Aphis fabae which alternates between various primary hosts (fusain, viburnum, Philadelphus/mock orange) and many secondary hosts (such as Fabaceae, Chenopodiaceae, Solanaceae)

• The rose-grain aphid: Metopolophium dirhodum which alternates between roses (HI) and diverse Poaceae (HII)

Illustration with the cycle of Rhopalosiphum padi:

Alternance d'hôtes entre l'hôte primaire (HI) Prunus padus (merisier à grappes) et les hôtes secondaires (HII) graminées cultivées ou sauvages

Copulation on Prunus padus	Eggs on Prunus padus	Fundatrix onr Prunus padus
Apterous virginopara and larvae on barley	Winged virginopara on wheat