Diaspidae

Common Name

Armored scales or Diaspidid scales

Overview

The family Diaspidae, commonly known as armored scales, consists of small, plant-feeding insects that form a hard, protective covering over their bodies. They are found worldwide and are significant pests of agricultural crops, ornamental plants, and trees.

Taxonomy

• Kingdom: Animalia
• Phylum: Arthropoda
• Class: Insecta
• Order: Hemiptera
• Superfamily: Coccoidea
• Family: Diaspidae

Key Characteristics

• Hard, protective covering (scale) that can be removed from the insect's body.
• Females are wingless and legless, often remain stationary for most of their life.
• Males are typically winged and used for mating purposes.
• Body shape can be circular, oval, or elongated depending on the species.
• Size ranges from 1 to 3 mm.

Life Cycle

• Egg: Laid underneath the female's protective scale.
• Nymph(crawler): The mobile stage that moves to new feeding sites.
• Second-stage nymph: Begins developing the hard scale covering.
• Adult: Females usually remain sessile while males become winged to locate females.

Behavior and Ecology

• Feed on plant sap via specialized mouthparts.
• Found on various parts of host plants including stems, leaves, and fruit.
• Often form large colonies and can infest their host plant extensively.
• Have both sexual and asexual reproduction, with some species capable of parthenogenesis.
• Main predators include lady beetles and parasitic wasps.

Notable Species

• Aspidiotus nerii (Oleander scale) - Common pest on oleander and other ornamental plants.
• Diaspidiotus perniciosus (San Jose scale) - Serious pest of fruit trees.
• Aonidiella aurantii (California red scale) - Significant pest in citrus groves.

Conservation

• Many species are controlled by natural predators and parasitoids.
• Biological control programs have been implemented in agricultural settings.
• Chemical control is often required for serious infestations, but resistance can develop.

Significance to Humans

• Can cause significant damage to agricultural crops, ornamental plants, and trees.
• Infestations lead to reduced plant vigor, aesthetic damage, and even plant death.
• Monitoring and management are required in both agricultural and urban environments.

Fun Facts

• Armored scales are among the most economically important groups of scale insects due to their pest status.
• The protective scale cover is often made of shed skins from previous molts and plant material.
• Some species can produce up to three generations per year in favorable conditions.
• Armored scales have been found in fossil amber dating back to the Cretaceous period.