Dimorphomyrmex, André, 1892

Wheeler, W. M., 1922, The ants collected by the American Museum Congo Expedition., Bulletin of the American Museum of Natural History 45, pp. 39-269 : 209-210

Formicinae

(Camponotinae of authors)

Worker mononomorphic or more-or less polymorphic, only in a few cases with pronounced dimorphism ( Dimorphomyrmex ). Frontal carinae often feebly developed and the elypeus is only exceptionally produced between them { Dimorphomyrmex , Gesomyrmex ); even then, it is not properly wedged in. Antennae 8- to 12-jointed, usually long and filiform; the funiculus rarely with a feeble 4- or 5-jointed club. Abdominal pedicel always formed by one segment, the petiole, which is usually scale-like; there is never a trace of constriction between the second and third abdominal segments and the stridulator}- organ is also lacking at the base of the third segment. Sting vestigial; the poison-glands are converted into a cushion of convolutions(Forel's pulvilliferous vesicle); the sting forms merely the sustentacular apparatus for the orifice of this poison vesicle. The ejaculation of the poison can in certain genera ( Formica ) be effected with great force. Orifice of the cloaca always circular and terminal, ciliated round the margin.

Female always winged and similar to the worker, though of much larger size.

Male winged, with the genitalia always exserted.

The venation of the wings is more or less reduced, often considerably so. In its most primitive stage there is still one cubital, a closed radial, and a closed discoidal cell; but there is no intercubitus, the radius and cubitus being confluent over a part of their course (Formica-type). Reduction has usually started by the disappearance of the recurrent vein, there being no discoidal cell ( Camponotus , Oecophylla ). An intercubitus is only rarely present and then very short ( Myrmoteras , which has the most primitive venation of this subfamily).

Nymphs usually enclosed in cocoons; but there are some exceptions ( Oecophylla , Prenolepis ).

The members of this subfamily are morphologically the most highly developed of all ants; this is also true for their ethological peculiarities. Not only are their habits very diverse, but they show the most specialized form of mental and social behavior. The diet is in large part vegetarian and these ants show great predilection for sugary substances, which are sometimes stored in a special, replete form of worker (honey ants: Melophorus , Myrmecocystus , certain Plagiolepis , etc.). The species of Oecophylla and certain Polyrhachis and Camponotus build silk nests in leaves, using their larvae as silk-producing shuttles. Moreover, the nesting habits in this subfamily are very varied. Certain species of Formica and Polyergus are slave-makers; the species of Polyergus are true social parasites of Formica , entirely dependent upon their slaves, but the worker caste is still present.