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Plantain aphidOn this page: Identification & Distribution Biology & Ecology: Colour Life cycle Ant attendance Natural enemies Other aphids on the same host
Identification & Distribution:
Adult Aphis plantaginis apterae are dark green, mottled to a greater or lesser extent with pale green. The antennal terminal process is 2.0-2.8 times the length of the base of the sixth antennal segment. Their abdominal sclerotic pattern is variable, with the most heavily marked having dark intersegmental muscle sclerites (see micrographs below), small marginal and postsiphuncular sclerites and bars across tergites 7 and 8. Marginal tubercles are rather large, especially in alates. The siphunculi are black and 1.62-2.42 times the length of the dusky cauda. The body length of Aphis plantaginis aptera is 1.23-2.04 mm.
The images below show adult apterous and alate Aphis plantaginis in alcohol.
Aphis plantaginis lives under the rosette leaves and on the root collar of great plantain (Plantago major), hoary plantain (Plantago media) and ribwort plantain (Plantago lanceolata). It does not host alternate. It is usually attended by ants which cover the aphid colony with soil particles. Sexual forms develop in autumn. Aphis plantaginis is widely distributed in southern Britain and throughout most of Europe and into Asia.
Biology & Ecology:
Aphis plantaginis adults are usually mottled with pale green and dark green to a greater or lesser degree which can provide excellent cryptic colouration on the stems and leaves of plantain. They are not wax powdered (note: the white dots on the backs of the aphids shown below are not wax, but droplets of condensed water after the specimens had been kept cool for a period and then warmed up).
The mottling is most marked in adults and varies from colony to colony (see pictures below). Immatures tend towards a more uniform green colour.
The overwintering eggs hatch in late spring, but in mild years some aphids probably overwinter as viviparae.
The earliest we have found colonies on plantain (as evidenced by ant tenting of the leaves) is late June.
Sexual forms develop in autumn - the picture below shows an ovipara.
Colonies are usually tented over with soil particles by Lasius ants which attend the aphids, as shown in the second picture below.
Most of the colonies we have found have been attended by and tented by Lasius niger (see picture below).
In Siberia Novgorodova & Gavrilyuk, 2012 found Aphis plantaginis was one of the most attractive aphids to ants, with 7 different species of ants attending the aphid.
In common with many of the root aphids, syrphid larvae are important predators. The picture below shows an (unidentified) syphid larva predating Aphis plantaginis.
Other aphids on same host: