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"It has long been an axiom of mine that the little things are infinitely the most important" |
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Aphis viburniViburnum aphidOn this page: Identification & Distribution![]() ![]() ![]() ![]() ![]() ![]() ![]() Identification & Distribution:Apterae of Aphis viburni are slate-coloured, brownish green or dark brown, sometimes with paired pleural wax spots on the abdomen. The sclerotic dark banding of the dorsum (just visible in the first picture below) is variable, confined to abdominal tergites 6-8 in smaller apterae, but with broken bands often present on some anterior tergites in larger specimens. Marginal tubercles are conspicuous (the brown lumps in the foreground of the second picture below) and subconical, very constant on tergites 1-4 but only irregularly on 5-6 (cf. Aphis fabae The dark banding of the dorsum is more regular in the alates (see second picture above). Males are wingless.
Aphis viburni can most readily be distinguished from Aphis fabae (which can also use Viburnum opulus - as a primary host) by the gall of strongly curled leaves (see pictures below) that it produces. Aphis fabae does not produce a gall. The gall provides shelter for both the aphids and attendant ants.
Aphis viburni does not host alternate but remains all year on Viburnum opulus (guelder rose). Sexual forms are produced in autumn. The viburnum aphid is found in southern England and over much of Europe. Biology & Ecology:SystematicsThere has been rather little research carried out on the viburnum aphid, despite (or possibly because of) a relatively comprehensive study being carried out 70 years ago by Jones (1946). The work that has been done has been focused on the place of Aphis viburni within the black aphids of the Aphis fabae group which include Aphis fabae, ColourOf all the 'black aphid' group, the viburnum aphid is probably the most variable in colour, at least in our experience.
Grey/black is probably the commonest colour form (see first picture above), but we have also found brownish-green (see second picture above) and red-brown (see picture below) colonies - all feeding on guelder rose in southern England.
As with other members of the 'black aphid' group, immature Aphis viburni often have white pleural wax markings (see pictures below for both the black form and the red-brown form), but no general wax dusting.
Ant attendanceAphis viburni is nearly always attended by ants which feed on the aphid honeydew, and in turn protect the aphids from predators. The pictures below show aphids of both the black and the brown form being attended by Lasius ants.
Other aphids on same host:Blackman & Eastop list 16 species of aphid Of those aphid species, Baker (2015) Damage and controlThe galled leaves may spoil the appearance of the ornamental shrub, but we are not aware of any measures taken to control this aphid.
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