There are multiple metric units to choose from! This tutorial goes through the process of choosing the best metric unit to use for measuring the mass of a given object.
The most common aphids on houseplants are the light green ones (pear aphids), but aphids can also be found colored pink, white, grey and black. Additionally, winged aphids can appear when colonies are established and fly to infect new plants. Juvenile aphids (nymphs) look like smaller versions of the adults.
Soybean aphid adults are small insects, with oval-shaped bodies around 1/16th of an inch in length. They are greenish-yellow in color, with dark eyes and a pair of tubes, called cornicles, projecting from the rear of their abdomen (Fig. 1).