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Red yarrow aphidOn this page: Identification & Distribution Biology & Ecology Other aphids on the same host
Identification & Distribution:
Apterae of Uroleucon achilleae (see first picture below) are red or brownish red with rows of black dorsal spots (cf. most Macrosiphini on Achillea are green or greenish mottled with red). Their antennae are pale with darker segments I, II and the tips of segments of the flagellum. Marginal sclerites and antesiphuncular sclerites are absent. Abdominal hairs are long and placed on rather large scleroites. The legs are yellow with the apical one third of femora and the bases and tips of tibiae black. The siphunculi are black, and cauda is yellow. The body length of Uroleucon achilleae is 2.4-2.6 mm.
The alate (see second picture above) is similar to the apterous adult, but has marginal and antesiphuncular sclerites and cross bars on abdominal segments VII and VIII. The ovipara has the basal half of the hind tibia dark and swollen.
Uroleucon achilleae feeds on the lower leaves of yarrow (Achillea spp.) where it can cause withering. It does not host alternate. Oviparae and alate males occur in October (sometimes earlier). It is found throughout most of Europe and has been introduced to California and Oregon in the USA.
Biology & Ecology:
In East Sussex we have found Uroleucon achilleae several times on the lower leaves of yarrow plants from July onwards.
On one occasion they were present in large numbers with the aphid Macrosiphoniella sejuncta, which appears to occupy the same niche (lower leaves of yarrow).
Perhaps their precise feeding positions differ, with one on the leaves and the other on the stem?
Lethmayer (1998) looked at the species composition of aphids on agricultural crops with weeds strips situated within them in Switzerland. Uroleucon achilleae, a little recorded aphid in Switzerland, was one of the aphid species only found in the weed strips. Since it does not attack crop plants, it may be a useful reservoir host for predators and pararasitoids which attack crop pests.
Other aphids on same host:
Uroleucon achilleae have been recorded from 18 Achillea species.