The first reports on stenogastrine wasps can be found in a book of Guérin de Méneville (1831) with the first known species, Stenogaster fulgipennis.

Henri Louis Frédéric de Saussure treated their systematic position and remarked that these wasps were, in all their characters, entirely intermediate between the two subfamilies of Eumeninae and Vespinae.

The mandibles are much more subtle with respect to those of polistine or vespine wasps: in the females they can have three teeth, but in the males of some species, their internal margin is almost straight.

Legs are short and feeble, while the fore wings are not folded longitudinally as occurs in polistine and vespine wasps.

The flight of these wasps is characteristic, and some genera (i.e. Parischnogaster, Metischnogaster and Eustenogaster) can hover in the air, remaining almost immobile like small dragonflies.

Females are able to fly close to spider webs to steal small prey; the males perform aerial patrolling during particular times of the day, hovering and protecting particular perching sites.

This gives these wasps a quite slender silhouette and makes them able to touch the end of the abdomen with the mouth parts when they bend the gastrum ventrally.

In all the species observed of at least three genera, it consists of three stages: after initial inspection of a cell, the female bends her abdomen ventrally towards her mouth parts and collects a patch of viscid abdominal substance which is produced in the Dufour's gland.

After stretching the abdomen, the wasp bends it again, with the sting extruded, towards her mouth and collects the egg as it emerges, allowing its concave surface to adhere to the patch of abdominal secretion.

Immediately after hatching, the larva curls itself around a mass of gelatinous secretion which covers the eggs produced by the Dufour's gland of the parent.

This is another important difference from the other social wasps where the larvae keep their body distended along the longitudinal axis of the cell and present only their heads at the cellular openings.

In fact, the colonies of hover wasps do not present rigid castes, and individuals are conditioned in their choices only by the contingent situation of the social environment in which they find themselves.

[9] A strict age-based inheritance queue seems to regulate the access to reproduction in this species: new dominants are the oldest female in their groups in most of the cases.

The males belonging to species of at least four of the oriental genera (Liostenogaster, Eustenogaster, Parischnogaster, and Metischnogaster) leave the nests and reach well-defined sites where they patrol localized territories of various kinds.

L. flavolineata males fly in circuits and land on perches where they rub their gastral tergites, probably releasing a marking pheromone.

Parischnogaster and Metischnogaster, instead, hover in flight near the perch, making visible now and then the whitish and shiny bands of their tergal gastra.

Stenogastrine nest architecture differs from that of other social wasps and has such an incredible variety of shapes, it has in some instances been used as a systematic character.

Stenogaster: The nest of S. concinna has a bell-shaped architecture, is formed by a low number of cells, and is built with 'soil' containing a few small pieces of vegetable matter.

Anischnogaster: The nests of A. iridipennis are built of fine mud with occasional small pieces of stone and vegetable matter incorporated into the structure.

Metischnogaster: The genus includes two species with the most highly camouflaged nests consisting of a row of cells, the first of which is attached with its bottom to the tip of a thread-like suspension.

The evolution of the nest architecture in these wasps has been especially determined by the pressure exerted by predators such as ants and tropical hornets.

Against the first ones, some species build special sticky, gelatinous structures, called "ant guards", formed with the secretion of the Dufour gland which are placed as barriers to the nests.