In a nutshell: Warm, humid conditions allow this species to thrive; pest of many ornamental plants; sap suckers—cause leaves to deform and yellow, excrete sticky “honeydew”; two long tail strands; nymphs are born live, the female does not lay eggs.
What are long-tailed mealybugs?
Long-tailed mealybugs are native to more tropical regions but are now widespread globally. This species prefers a warm, humid environment. It often hides in concealed, protected parts of the plant as a result. They can reproduce both sexually and asexually, but asexual reproduction is more common
What kinds of plants do they attack?
Like the citrus mealybug, this species also attacks fruit trees and ornamentals. However, it has a smaller range of host plants. The long-tailed mealybug is a pest of croton, orchids and grapes. It also affects trees such as avocado, apple and citrus.
What do they look like?
Adult females are 3–4 mm in size and more elongated than the citrus mealybug. They appear oval shaped from above and move very little. Long-tailed mealybugs are soft and covered with a powdery white wax. The insect is also fringed by white wax strands about half as long as its body is wide. You can distinguish this species from other mealybugs by the long “tail strands” on its rear end. These strands are at least as long as the insect’s body.
Adult males are short lived, hard to spot and not as common as females. They’re smaller (only around 1 mm long), have two pairs of wings and two very long tail filaments. They fly around only in the early morning, have no mouthparts for feeding and exist only to mate. As soon as a male emerges from its cocoon, it goes in search of a female.
Whether she mates or not, the female mealybug bears live young as first-stage nymphs. Initially, she keeps the nymphs underneath her body in a network of fine, waxy threads. These nymphs, called “crawlers”are small (around 0.6 mm long by 0.2 mm wide), pink and mobile. Later nymph stages more resemble the adult female. The nymphs actively search for a new feeding spot on the plant. At this stage, they are able to move around the plant or across other surfaces.
The male nymph attaches itself to the plant, then it forms a dark brown “pre-pupa." This quickly develops into a pupa inside a white, cottony cocoon. The female remains mobile throughout her entire development and changes form very little. After completing the third nymph stage, the female becomes an adult and starts releasing a chemical that attracts males.
How do I know if my plants are under attack?
Mealybugs can be found on all parts of the plant, but they prefer growing tips and the areas where leaf stem and plant stem intersect.
Nymphs and adult females feed on the plant’s vital sap. This stunts growth, causes leaves to become deformed or yellow, and sometimes leads to defoliation. This has the general effect of reducing photosynthesis and yield. Often flowers and fruit will drop off the plant.
Excess sugar from the sap is excreted on leaves and fruit surfaces as a sticky “honeydew”. Black fungal moulds will often grow on this substance, further reducing photosynthesis and contaminating fruit.
Growth of black mould and the white, waxy secretions left behind by the mealybugs ruin the ornamental value of plants.
How to get rid of Long-tailed mealybug
Koppert offers different solutions for biological pest control of Long-tailed mealybug.