Invertebrates—Identifying Mealybugs

Grape mealybug
Identification tip: Grape mealybugs (as all Pseudococcus mealybugs) are roughly 1/4 inch long, flat, oval shaped, and have a white waxy covering with wax filaments sticking out from the circumference of the body. Longer filaments from the posterior end make these mealybugs appear to have "tails."

Obscure mealybug
Identification tip: The obscure mealybug and grape mealybug closely resemble each other. One method of distinguishing them in the field is to poke a female with a sharp point (without puncturing the body) to elicit the release of a defensive excretion. If the color of the fluid excreted is reddish orange, then it is most likely grape mealybug; if it is clear, it is most likely obscure mealybug.

Grape mealybug
Identification tip: The fluid that exudes from a punctured female grape mealybug tends to be orange to red.

The fluid that exudes from the obscure mealybug after being punctured tends to be yellow to clear.

Vine mealybug
Identification tip: The body shape is oblong. The waxy filaments that protrude from the body of the vine mealybug are shorter and appear thicker or stubbier than those on the Pseudococcus mealybug. The vine mealybug does not possess long tail filaments.

Longtailed mealybug
Identification tip: Longtailed mealybugs are similar in appearance to the grape and obscure species, but have much longer waxy filaments on the posterior end—as long or longer than the body of the adult female.