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Ivy aphidOn this page: Identification & Distribution Biology & Ecology: Life cycle Ant attendance Natural enemies Other aphids on the same host
Identification & Distribution:
The apterae of Aphis hederae are dark greenish (see first picture below) or reddish brown (see second picture below) although immatures are paler. They are supposedly not waxy, although the immatures here appear to have a wax 'bloom'. The antennae are mostly pale, only darkened from the middle of segment V to the apex, with the terminal process 1.8-2.8 times the length of the base of segment VI. The fused apical rostral segment (RIV+V) is 1.35-1.60 times the length of the second hind tarsal segment (HTII). The abdominal sclerotic pattern of Aphis hederae is mostly confined to a band on abdominal tergites 6-8 with small marginal and postsiphuncular sclerites, and often a few small spinal scleroites on some of tergites I-V. The siphunculi are 1.33-1.90 times longer than the rather short bluntly tapering cauda. The body length of Aphis hederae apterae is 1.4-2.5 mm.
The alate (see third image above) has strong transverse dark bands on most tergites.
The ivy aphid does not host alternate. It feeds on ivy (Hedera helix) living on the young shoots and foliage (Stroyan, 1984). Aphis hederae can also be found on various house plants in the Araliaceae such a Fatsia and Schefflera. Sexual forms occur in autumn with apterous or alate males. It occurs throughout Europe, the Middle East and parts of Asia. It is also recorded from North America, South Africa and New Zealand.
Biology & Ecology:
Aphis hederae is common and widespread in Europe on ivy growing on old walls and on trees. Overwintering eggs laid on the ivy in autumn hatch in spring.
Numbers increase rapidly by parthenogenesis to give large populations by early summer. As well as feeding on ivy, Aphis hederae can also be a pest on various house plants as shown below on an octopus tree (Schefflera umbellifera).
These are oviparae found at the end of September.
Aphis hederae is facultatively attended by ants, in our experience most commonly by Lasius species.
The only predators we have encountered are mites. The first (see picture below) is possibly an Anystis species.
The second is a parasitic trombidiid mite (see picture below). These only kill if there are several on the same aphid, but they certainly reduce the fecundity.
The apparent scarcity of aphid-specific predators may result from the toxicity of some members of the Araliaceae (Maharaj et al., 2008). In addition the presence of generalized predators may disrupt biological control by other more specific natural enemies (Messelink et al., 2011).
Other aphids on same host:
Blackman & Eastop list 12 species of aphid as feeding on ivy (Hedera helix) worldwide, and provide formal identification keys (Show World list). Of those aphid species, Baker (2015) lists all 12 as occurring in Britain (Show British list).