SCIENTIFIC NAME: Phenacoccus gosspii Townsend and Cockerell
CLASS: Insecta
ORDER: Hemiptera
FAMILY: Pseudococcidae
Description
Adults
The female Mexican mealybug adult is 3 to 4 millimeters long, oval, grayish and covered with a thin wax secretion. There are three parallel rows of small wax tufts down the back. This insect is a short-tailed mealybug (the caudal filaments do not exceed 1/4 the body length). The lateral filaments are also short. Males are small gnat-like insects with onl two wings. Adult Mexican mealybug males have four wax, posterior filaments.
Eggs
The egg sac is white, dense, narrow, and longer than the female secreting it.
Nymphs
The nymphs are small and yellowish with white wax secretions.
Biology
Host Plants
The Mexican mealybug is found commonly on numerous ornamental plants, a few of which are araliya, chrysanthemum, English ivy, geranium, Gynura, hollyhock, lantana, and poinsettia. This insect is also a minor pest of lima beans in the warmer parts of the United States.
Damage
Wilting and stunting are common symptoms of Mexican mealybug attack. This insect can be as damaging as the citrus mealybug. The mealybugs and ovisacs also disfigure heavily infested plants.
Life Cycle
In the greenhouse, the Mexican mealybug may have seven complete generations in one year. The average time required from oviposition to the adult stage is 47 days. Each female deposits about 400 eggs. The eggs are enclosed in an elongate cotton mass called the ovisac that originates at the back of the female. The ovisac is about 6 millimeters long. The eggs hatch in 6 to 14 days. The life cycles of the male and female Mexican mealybugs differ. A female passes through three nymphal stages only. Male Mexican mealybugs pass through two nymphal stages and two resting stages (prepupal and pupal stages). Normally, these mealybugs are found above ground on the leaves, stems or flowers, but occasionally will be found feeding on the roots.
Management Strategies
Pesticides
For chemical control recommendations, consult the Extension Service.