Diaspididae

Diaspididae, commonly known as armored scale insects, is a large family within the superfamily Coccoidea of the order Hemiptera. Members are small sap-sucking insects that produce a hard, plate-like protective covering secreted by the body. The shield adheres tightly to the insect and remains on the body as it ages, making adults often immobile. Males are typically winged and short-lived, while females are usually sessile.

Life cycle and anatomy: Female armored scales brood eggs beneath or within the covering. After hatch, the mobile first instar nymphs, or crawlers, disperse to new feeding sites. They settle and molt into wingless adults. The distinct protective cover gives armor-like protection against some predators and pesticides.

Ecology and feeding: Diaspidids feed on plant sap by inserting their clear mouthparts into vascular tissue. They occur on a wide range of hosts, including ornamentals, fruit trees, and forest species. Infestations can produce honeydew, which promotes sooty mold and can attract ants. The sessile nature of adults can make populations dense if not controlled.

Diversity and distribution: The family contains hundreds of genera and thousands of species with a cosmopolitan distribution, especially in warmer climates and in greenhouses.

Economic importance and management: Armored scales are important pests in agriculture and horticulture, affecting fruit crops, citrus, grapes, and ornamentals. Management relies on regular monitoring, horticultural oils, systemic insecticides, and biological control using parasitoid wasps and predatory insects. Sanitation and removal of infested plant material can also help reduce populations.

Taxonomy: Diaspididae is part of Hemiptera, suborder Sternorrhyncha, within the superfamily Coccoidea. Notable pests include the San Jose scale (Quadraspidiotus perniciosus) and other citrus and fruit-tree scales.