Worldwide there are about 1000 species and subspecies in subfamily Dolichoderinae placed in 22 genera (Shattuck, 1999. Australian Ants: 64). Species of Dolichoderinae can be found throughout the world in many different habitats. They are most abundant and diverse in the Australian region where they are the dominant ants in many areas. There are 31 species in 8 genera in the Nearctic region where they are found primarily in the southern portion of the United States.
Dolichoderinae is a monophyletic subfamily with the following autapomorphies (Shattuck, 1992b: 203):
and the following larval characteristics:
Together, subfamilies Dolichoderinae, Formicinae and Aneuretinae (represented by a single species found only in Sri Lanka) also form a monophyletic group. These three subfamilies are believed to have split off very early in evolutionary history from the lineage of the remainder of the ants. This split is estimated to have occurred about 100 million years ago (Grimaldi & Agosti, 2000: fig. 2).
Recognition. In the field, ants of this subfamily can usually be recognized by their small size, petiole a single segment, thin often translucent integument and their characteristic odor. Under the microscope, the sting is absent and the opening at the tip of the gaster is slit-like. This slit-like opening is difficult to directly observe but is usually inferred by the absence of an acidopore (circular opening usually fringed by hairs). The gaster is smooth and the segments are not separated by constrictions.
Similar Subfamilies. Species of Dolichoderinae are often confused with species of subfamily Formicinae because both a have a single segmented petiole, lack a sting, and often are of similar body size and shape. Doichoderines always have a slit-like opening at the tip of the gaster whereas formicines have an acidopore (small circular opening that is often fringed by hairs). Most Nearctic dolichoderines have a very thin integument (Dolichoderus is the exception) while most formicines have a thicker integument (exceptions being Brachymyrmex and the uncommonly collected genus Plagiolepis). Members of subfamily Ponerinae are also small and have a single segmented petiole. Ponerines always have a well developed sting although it may be retracted into the gaster and impossible to see. Additionally, ponerines have a constriction between the first and second gastral segments (absent in the ponerine genera Odontomachus and Anochetus which are easily identified by their long, linear mandibles).
Nearctic Genera. Dolichoderus, Dorymyrmex, Forelius, Linepithema, Liometopum, Ochetellus, Tapinoma, Technomyrmex
Non-Nearctic Genera. Amyrmex, Anillidris, Anonychomyrma, Axinidris, Azteca, Bothriomyrmex, Doleromyrma, Ecphorella, Iridomyrmex, Leptomyrmex, Loweriella, Papyrius, Philidris, Turneria
Tribes. Subfamily Doclichoderinae is not currently divided into tribes. However, both the morphological and molecular evidence provides strong support for two groupings: { Liometopum, Tapinoma, Technomyrmex }, { Anonychomyrma, Iridomyrmex, Ochetellus, Papyrius, Linepithema, Forelius } (Shattuck, 1995 and Chiotis, Jermiin & Crozier, 2000. Mol. Phylogenet. Evol. 17).
Revisions. Shattuck, 1992c: 1-181 (genus-level revision of the subfamily, each genus has a diagnosis for w.q.m.).
Taxonomy. Shattuck, 1992b: 199-206 (phylogeny of Formicinae, Dolichoderinae, and Aneuretinae based on morphology).—Shattuck, 1994: 1-241 (taxonomic catalog).—Shattuck, 1995: 217-228 (phylogeny of the dolichoderine genera based on morphology).—Chiotis, Jermiin & Crozier, 2000. Mol. Phylogenet. Evol. 17: 108-116 (phylogeny of the dolichoderine genera based on sequences of three mitochondrial genes, the conclusions largely support those of Shattuck, 1995).