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Yarrow root aphidOn this page: Identification & Distribution Biology & Ecology Other aphids on the same host
Identification & Distribution:Adult Aphis vandergooti apterae are dark blue-green (or rarely yellow) without any wax powdering. There is usually no dorsal abdominal sclerotic pattern, or there may be narrow bands across tergites 7-8. The siphunculi are tapering, usually widening slightly at the apex with a very small apical flange, and 1.93-2.57 times the length of the cauda. Marginal tubercles are large and conspicuous but rather flattened. Leg hairs are all very short, much shorter than the least width of tibiae. The body length of Aphis vandergooti apterae is 1.4 to 2.0 mm.
Aphis vandergooti alatae are dark blue-green and have 3-7 secondary rhinaria on the third antennal segment. The micrographs below show dorsal and ventral views of an aptera in alcohol. The conspicuous, rather flattened, marginal tubercles are clearly shown.
Aphis vandergooti does not host alternate. It lives in ant shelters on the roots, stolons and basal leaf petioles of composite plants of the tribe Anthemideae, especially yarrow (Achillea millefolium), wild chamomile (Matricaria), and tansy (Tanacetum vulgare). Apterous males are produced in autumn. In Britain Aphis vandergooti is widely distributed, but not very much recorded. It is widespread in Europe, but apparently commoner in northern Europe.
Biology & Ecology:
We have found Aphis vandergooti in two locations in southern Britain: a lay-by on the Clifton-Shefford bypass in Bedfordshire, and a housing estate in East Sussex. Aphis vandergooti colonies are invariably tented over and attended by ants often by Lasius niger. Woodring et al. (2004) found that Aphis vandergooti takes up much more phloem sap than needed for a minimum of dietary amino acids, and hence can secrete a large volume of melezitose-enriched honeydew. The sole purpose of the sugar-rich honeydew is to solicit the protective services of ants. Those species (e.g. Macrosiphoniella tanacetaria ) that do not solicit ants have no need of a sugar-rich honeydew with a high melezitose titre, and only low levels of amino acids and sugars are found in the honeydew.
Depa & Wegierek (2011) looked at the species composition of aphid fauna within the nests of Lasius flavus in three vegetation types: a Molinietum wet meadow, an intensively trodden on and regularly mown Lolio-Polygonetum arenastrii meadow in a housing estate and Festuco-Stipion xerothermic grassland. Aphis vandergooti was only found in nests on the roots of Achillea millefolium and Bellis perennis in the housing estate meadow, which was where the most aphid species rich ant nests were located.
Other aphids on same host:
Blackman & Eastop list 46 species of aphid as feeding on yarrow (Achillea millefolium) worldwide, and provide formal identification keys.
Of those aphid species, Baker (2015) lists 26 as occurring in Britain: Aphis craccivora, Aphis fabae, Aphis gossypii, Aphis vandergooti, Aulacorthum solani, Brachycaudus cardui, Brachycaudus helichrysi, Coloradoa achilleae, Macrosiphoniella abrotani, Macrosiphoniella millefolii, Macrosiphoniella ptarmicae, Macrosiphoniella sejuncta, Macrosiphoniella tanacetaria, Macrosiphoniella tapuskae, Macrosiphoniella usquertensis, Macrosiphum euphorbiae, Metopeurum fuscoviride, Microsiphum millefolii, Myzus ascalonicus, Myzus cymbalariae, Myzus ornatus, Myzus persicae, Neomyzus circumflexus, Pleotrichophorus duponti, Trama troglodytes and Uroleucon achilleae.