These small insects are soft bodied and pearshaped and live in tightly packed colonies on plants. They come in a variety of colours and depending on the species and time of year, can be pale green, yellow-green, dark green, purple, brown or black. They have slender antennae and have two tubular projections at the rear of the body which are called cornicles. They can be either winged or wingless species. Sometimes, the castoff skins of the aphids, which are white or translucent, adhere to the plants in and around the colony and these can sometimes be confused with...

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