One of the newest pests in South Florida is the Rugose Spiraling Whitefly. This pest was first found in 2009 and has since spread from Miami up to Melbourne on the East Coast and up to Ft Meyers on the West Coast of South Florida. Unlike other whiteflies that are small and barely visible, the Rugose Spiraling Whitefly is larger (1/8") and resembles a small moth.
The Rugose Spiraling Whitefly belong to the Order Hemiptera which also includes aphids, scales, and mealybugs. These insects typically feed on the underside of leaves with their "needle-like" mouthparts. This whitefly hasn't yet been shown to cause any permanent damage to any host plants. However, the primary problem is the extremely large amount of honeydew produced by this insect. The honeydew coats everything below in a sticky sap-like mess.
Description and Damage
The list of host plants for Rugose Spiraling Whitefly is constantly growing. These pests don't appear to be host specific. However, several species of plants seem to be favored. Coconut palms, white bird-of-paradises, and Gumbo Limbo trees are the top three favorite hosts. Other common hosts include: most palm species, avocado, oak trees, black olives, sea grapes, wax myrtles, etc.
As mentioned above, Rugose Spiraling Whitefly don't appear to injure the plant like other whitefly, but do produce an unbelievable amount of honeydew. Honeydew is fecal secretions of certain insects that resemble tree sap. This insect produces so much honeydew your feet may stick to the ground below. There are reports of Rugose Spiraling Whitefly from a single coconut tree in a parking lot coating all cars within 50 feet in honeydew. To make matters worse, Sooty Mold may also form on the honeydew creating a black "sooty" appearance on all surfaces below the tree.
The adult whitefly resembles a small moth (1/8") with a whiteish-yellow body and white mottled wings. Immature stages (eggs and nymphs) can be found primarily on the underside of the leaves. Rugose Spiraling Whitefly can be identified by the distinct "spiraling" pattern of their egg masses. In severe infestations the entire underside of the leaves is coated in white egg masses and the pattern is less apparent. Rugose Spiralling Whitefly egg masses will also be found on nearby non-host plants and even concrete!
Monitor your landscape plants for early signs of an infestation because it is better to prevent infestations than it is to try to fix severe infestations. Honeydew and Sooty-mold may remain for months after the Rugose Spiraling Whitefly are gone.
The exact biology of the Rugose Spiraling Whitefly is not known, however, it is probably similar to related species in South Florida. Eggs which are usually laid on the underside of leaves hatch into a crawler stage. The crawler wanders around the leaf until they begin to feed. From this point until they emerge as adults, they are immobile and remain in the same place on the plant. These feeding, non-mobile stages (nymphs) are usually oval, flat, and simple in appearance.
Do you live in South Florida and think this pest may be invading your landscape? Hulett Environmental Services offers specialty design spiraling whitefly treatments to control and eliminate this pest!