Tessellated scale

The tessellated scale (Latin: Eucalymnatus tessellatus) is a common pest of indoor and greenhouse plants, belonging to the order Hemiptera and the family Coccidae. The adult female is characterized by a flat, dark brown, shield-like body with a distinct tessellated or mosaic-like pattern on its surface.

This insect is a polyphagous pest that affects a wide variety of ornamental plants. It is commonly found on indoor tropical species such as palms, orchids, ficus, anthuriums, and bay trees. In closed environments, it can thrive year-round, exploiting the stable conditions of homes and commercial greenhouses.

The life cycle involves eggs laid beneath the female's protective shell. Upon hatching, the mobile crawlers move across the plant surfaces to find suitable locations to insert their mouthparts and begin feeding on sap. Once they settle and begin to feed, they become immobile and secrete the characteristic protective shield.

Damage is primarily caused by the removal of sap, which stunts growth and causes chlorosis (yellowing of leaves). Furthermore, these insects excrete large amounts of honeydew, a sticky substance that promotes the growth of sooty mold, which impairs photosynthesis and reduces the overall ornamental value of the plant.

To control an infestation of tessellated scale, growers should follow these integrated management practices:

• Manually remove scales using a soft brush dipped in insecticidal soap or rubbing alcohol.
• Isolate infested plants immediately to prevent the spread to healthy specimens.
• Apply systemic insecticides that are absorbed by the plant and kill the pests during feeding.
• Conduct frequent inspections of the undersides of leaves and leaf nodes to detect early signs of activity.