We have some new insects on the elephant food plant in the back yard.
They are oval and covered with white wax. Do you know what they are?
These rover ants know what the white insects are: a source of honeydew. The ants will defend the white insects and move them around to better sources of food.
The white insects are mealybugs. The two under the ant have just molted, shedding their waxy coats. Can you see the shed exoskeletons towards the lower end of the pile (they are open at the back)? Seems likely the mealybugs are most vulnerable right after molting.
Sometimes we find insects in places we did not expect.
Take these red potatoes from the grocery store. When they started to sprout, I set them aside to plant in the garden. A short time later, they looked like they were beginning to mold.
Looking closer, it became apparent it wasn't mold at all. Insects called mealybugs were feeding on the sprouts.
Mealybugs are relatives of aphids and cicadas. Like some of their relatives, they are covered with a waxy powder, which gives them the white color.
Can you spot the nymph in this photograph that has recently molted and lost its waxy covering temporarily?
Mealybugs suck the juices from plants. They excrete the excess plant juices in the form of honeydew, which is a wet, sticky fluid. Scientists speculate the waxy covering helps prevent them from drowning in their own honeydew.
It turns out that scientists have already discovered that different species of mealybugs have an affinity for sprouting potatoes. In fact, people rearing mealybugs for experiments, or to produce biological control agents, use sprouting potatoes to maintain their laboratory colonies.
Looking for an easy insect to rear for a science project? Consider the humble mealybug!