Duplaspidiotus fossor

Systematic position. Duplaspidiotus fossor belongs to the order Hemiptera and the family Diaspididae. It is commonly referred to as an armored scale insect, characterized by the protective waxy covering produced by the female, which shields it from environmental stress and many contact pesticides.

Host plants. This species is known to infest a variety of woody plants and ornamental shrubs. It shows a preference for specific tropical and subtropical botanical families, often colonizing the bark of branches, twigs, and occasionally the foliage of its hosts.

Biology and life cycle. The life cycle involves an egg stage, a mobile crawler stage, and a sessile adult stage. The crawler is the primary dispersal phase, moving to suitable feeding sites before settling and secreting its characteristic armor. Multiple generations can occur annually depending on local climatic conditions and temperatures.

Damage and pest status. The pest causes damage by inserting its stylets into the plant tissue to extract sap. This feeding process leads to reduced vigor, leaf chlorosis, yellowing, and if the infestation is severe, dieback of the branches. The accumulation of scale insects can drastically diminish the aesthetic value of ornamental plants and decrease fruit yields.

Control measures. Management requires an integrated approach.

• Regular pruning of heavily infested wood.
• Application of horticultural oils during the dormant season to suffocate overwintering stages.
• Use of systemic insecticides when crawlers are active.
• Monitoring programs to time applications effectively against the most susceptible juvenile stages.