Heteroecy
Guides
Aphis fabae
black bean aphid, blackfly, bean aphid, beet leaf aphid
Aphis fabae is a small, soft-bodied aphid in the family Aphididae, commonly known as the black bean aphid or blackfly. It is a significant agricultural pest with a broad host range, attacking beans, sugar beet, and numerous other crops. The species exhibits a heteroecious life cycle with host alternation between a woody primary host (Euonymus europaeus, spindle tree) and herbaceous secondary hosts. It reproduces parthenogenetically during the growing season and sexually in autumn, producing overwintering eggs. The aphid is capable of rapid population increase through viviparous reproduction, and winged forms develop seasonally to facilitate migration between host plants.
Brachycaudus helichrysi
leaf curl plum aphid, leaf-curling plum aphid, peach leaf curl aphid
Brachycaudus helichrysi is a small aphid species first described by Kaltenbach in 1843. Molecular studies have revealed it comprises two cryptic sibling lineages, B. helichrysi H1 and H2, which are morphologically indistinguishable but genetically divergent and differ in life cycle strategies. H1 follows a typical heteroecious cycle with sexual reproduction on plum trees, while H2 consists largely of obligate asexual superclones with some sexual populations on peach trees in India.
Kaltenbachiella ulmifusa
Slippery Elm Gall Aphid
Kaltenbachiella ulmifusa, commonly known as the Slippery Elm Gall Aphid, is a gall-forming aphid species in the family Aphididae. It induces distinctive galls on elm trees (Ulmus spp.), particularly on slippery elm (Ulmus rubra). The species is native to North America and has been documented primarily in the eastern and central United States. Like other members of the subfamily Eriosomatinae, it exhibits a complex life cycle involving host alternation.