Tokyo scale

The Tokyo scale (Lepidosaphes tokionis) is a destructive plant pest belonging to the Diaspididae family within the order Hemiptera. This armored scale insect is particularly problematic in greenhouses and orchid collections, where it acts as an obligate parasite feeding on the sap of its host plants.

This species predominantly targets epiphytic orchids, specifically affecting genera such as Cattleya and Dendrobium. The pest typically congregates on pseudobulbs and leaf surfaces, where it remains firmly attached for the duration of its feeding cycle, making it difficult to detect during early infestations.

The life cycle consists of the egg, the mobile crawler stage, the nymphal stage, and the sedentary adult. The crawler stage is the only time the insect is mobile and vulnerable to control measures. Once the crawler selects a feeding site, it settles down and begins secreting a waxy armor, which provides excellent protection against environmental stress and many contact insecticides.

Damage caused by the Tokyo scale is characterized by localized chlorosis and the development of unsightly spots at the feeding sites. Persistent infestation leads to stunted plant growth, the shriveling of pseudobulbs, and overall plant decline. In severe cases, failure to treat the infection will lead to the death of the orchid.

Effective management requires a combination of cultural and chemical strategies.

• Implementation of strict quarantine protocols for any new plant arrivals.
• Application of systemic insecticides that are absorbed by the plant and kill the scale during feeding.
• Regular inspection of the underside of leaves and base of pseudobulbs for early detection.
• Physical removal of armored scales using soft brushes or swabs with insecticidal solutions.