Ghost Ant:Tapinoma Melanocephalum

Ghost ants, Tapinoma melanocephalum, are a common household pest found in the Florida area. Although it was thought that this ant was confined to the southern portions of Florida, it has been reported as far north as Orlando even into Alachua county. This article discusses the basics behind ghost ants and how to potentially control them.

The ghost ant is associated with the "tramp ant" species that is generally found in tropical and subtropical latitudes. Although well established in states such as Florida and Hawaii, they are found throughout the world in countries such as Canada, Puerto Rico, and the Caribbean Islands.

Ghost ant workers are extremely small ranging in size from 1.3 to 1.5mm. They have 12-segmented antennae which thicken towards the tip. Workers are monomorphic. A distinguishing feature of the ghost ant is the color variation. The head and thorax are generally a darker color while the abdomen and legs present as opaque or white. Due to the small size as well as pale color, ghost ant workers are generally difficult to see.

This species tends to eat a variety of foods. It has a preference to sweet items and is commonly seen around sugar, cakes, and syrups. In the outdoors, workers have been seen scavenging for dead insects and sap-sucking insects trying to collect honeydew. This has presented a problem for greenhouses as the ant tends to defend honeydew producing plant pests as they share a symbiotic relationship.

Ghost ants will news readily both outdoors and indoors. Their preferred nesting sites include moist grass, plant stems, electrical outlets, sinks, voids in cabinetry and walls as well as baseboards. Reports indicate that they will also nest in potted plants. Multiple queens may be spread out into multiple subcolonies. Foragers that are found indoors often come from an outside source.

Colonies of ghost ants are very difficult to control. They tend to move from overpopulated nests and are highly mobile. If a colony is located, a contact insecticide may be applied however this generally is only a temporary solution. The most effective route of control is the tactic of liquid baits. Since these ants favor sugar, a combination of Boric acid (1-5%) in either sugar or honey water are an effective means of control. There are many different commercial liquid bait traps. The photo illustrates the use of Terro liquid bait traps which contain 5.4% Boric acid.

Other general tips for limiting ghost ant infestation include elimination of debris which could serve as nesting sites. Landscape and mulch should be less than 2 inches thick and at least a foot away from foundations. Cracks and voids on the home's exterior should be sealed to prevent nesting. Do not allow any water to stand and turn sprinkler heads away from the house foundation. If all methods as mentioned above do not control the ant infestation, a licensed professional should be contacted.