Tapinoma

Tapinoma workers are often encountered foraging on low vegetation or when nests are found. They can be quite common and forage at all times of the day and night. Nests are found in a wide range of sites, including open soil, soil covered with rocks, between rocks, wood or other plant material, in rotten or dead wood and plant stems, or almost any appropriately-sized preformed cavity. Individual nests may be small, containing from a dozen to several hundred workers together with one to several queens, or large with many thousands of workers and hundreds of queens (polygynous). Colonies are often composed of several nests spread over a small area.

They are general scavengers but have a preference for honeydew and often tend aphids or coccids. They are fond of sweets and can be collected using honey baits on trees, especially at night. One species, T. melanocephalum, is a pest widely distributed in tropical regions by commerce. This species forms large nests and will readily move indoors in search of food and water. A few species have major workers with round, truncated heads (they are phragmotic) which they use to block the entrances to their arboreal nests.

Identification
Mandibles with 3 or 7 large teeth and about 7 small denticles, and with the surface containing the teeth and the surface near the clypeus rounding gradually into one another (basal angle absent). The upper surface of the propodeum is shorter than the rear surface. The node of the petiole is absent and its forward face is either lacking or is very short and indistinct. The first segment of the gaster projects forward and partially or completely conceals the petiole when viewed from above. The gaster has 4 segments on its upper surface.

Tapinoma workers are most often confused with workers of Arnoldius, Doleromyrma, Plagiolepis and Technomyrmex because of the overall similarity in size and body shape. They can be separated from the first three by the complete lack of a petiolar node (these have a distinct forward face which is missing or is indistinct in Tapinoma) and the lack of an angle on the mandible between the face with the teeth and the face near the clypeus (a basal mandibular angle is present in the others). In addition, the eyes in Arnoldius are often much smaller than those in Tapinoma, and Plagiolepis belongs to the subfamily Formicinae and has a small circular opening (acidopore) at the tip of the gaster (the tip of the gaster is slit-like in dolichoderines).

Separation of Tapinoma from Technomyrmex is based on the gaster. In Tapinoma, there are four segments on its upper surface while in Technomyrmex the gaster has 5 segments on its upper surface (although the fifth may be small and retracted in some specimens). In addition, Technomyrmex workers are generally larger than Tapinoma workers and are black rather than brown.

Distribution and Habitats
Australian distribution

Regional Species Lists

 * Australia

Keys to Species

 * Australia