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Identification & Distribution:Adult apterae of Aphis umbrella (see first picture below) are pale green or yellowish green usually mottled with darker green. The abdominal dorsum in apterae is quite pale. The siphunculi in apterae are usually pale, often becoming slightly dusky at the apex. The siphunculi are 1.53 to 2.06 times the length of the cauda. The body length of Aphis umbrella apterae is 1.7-2.3 mm.
In alatae (see second picture above) the sclerotic pattern is confined to rather pale postsiphuncular and marginal sclerites and sometimes pale and inconspicuous bands across tergites 7-8. The siphunculi are uniformly dusky. Aphis umbrella alatae have 4-13 secondary rhinaria distributed on the third antennal segment, 0-5 on the fourth, and 0-1 on the fifth antennal segment.
Aphis umbrella feeds on mallows (Malva spp.) and certain other Malvaceae, causing umbrella-like leaf-curl pseudogalls of the terminal leaves. It does not host alternate. Sexual forms appear in autumn, although reproduction is probably entirely parthenogenetic in warmer climes. It is often ant-attended. In Britain the umbrella aphid has long been known from coastal localities in Sussex, Essex and Suffolk. It has more recently been recorded in several sites in Wales and Dorset. Aphis umbrella is found in Europe, Middle East and Central Asia and has been introduced to North America.
Biology & Ecology:
We have found Aphis umbrella in umbrella-like pseudo-galls of the terminal leaves of common mallow (Malva sylvatica) in both East Sussex (Alfriston) and West Sussex (Shoreham-by-Sea) in Britain (see pictures below).
We have also found Aphis umbrella along the Dorset coast at Arne, Seatown and Easton. Baker (2009) recorded Aphis umbrella in June 2006, in umbrella shaped 'pseudo-galls', formed from Lavatera arborea leaves, on plants growing on the edge of coastal cliffs at St. Justinians, Pembrokeshire. They were also observed in July 2007 and 2008, in umbrella 'pseudo-galls', formed from Malva sylvestris leaves, on 'brownfield' land in Cardiff Bay.
There is no sign of any wax spots on the adult apterae of Aphis umbrella (see picture below),
Aphis umbrella are sometimes attended by ants. On one occasion we found them attended by Lasius niger (see pictures below). Baker (2009) found them attended by Lasius niger and Formica fusca.
We did rear out some aphid parasitoids, so far unidentified (see picture below).
We also observed syrphid larvae (see below) predating Aphis umbrella.