Malleids

Malleids are a family of insects belonging to the order Hemiptera. They are commonly known as scale insects or bark lice. This group is characterized by a flattened, scale-like body and a sucking mouthpart adapted for feeding on plant sap. Malleids are found worldwide, in a variety of habitats, and are often associated with trees and shrubs.

The life cycle of malleids typically involves incomplete metamorphosis, with egg, nymph, and adult stages. The nymphs are mobile and resemble smaller versions of the adults. As they grow, they molt several times. Adult malleids are often wingless, though some species do possess wings. A distinguishing feature of many malleids is the production of a protective waxy coating or a secreted scale, which gives them their common name. This scale can vary in appearance, from thin and cottony to hard and shell-like, and serves to protect them from predators and desiccation.

Malleids are considered plant pests by many, as their feeding can weaken plants, distort growth, and transmit plant diseases. However, some species also play a role in ecosystems, serving as a food source for other insects and birds. Their classification within Hemiptera places them alongside other sap-feeding insects like aphids and cicadas. Research continues to explore the diversity and ecological significance of these often overlooked insects.