Platygastrinae Sceliotrachelinae The hymenopteran family Platygastridae (sometimes incorrectly spelled Platygasteridae) is a moderate-sized group (about 1100 described species) of exclusively parasitoid wasps, mostly very small (1–2 mm), black, and shining, with geniculate (elbowed) antennae that have an eight-segmented flagellum.

The former subfamily includes some 40 genera, all of which are koinobionts on cecidomyiid flies; the wasp oviposits in the host's egg or early instar larva, and the wasp larva completes development when the host reaches the prepupal or pupal stage.

The latter subfamily is much smaller, including some 20 genera, and they typically have the rudiments of a vein in the forewings.

For a brief period of time, Scelionidae was considered a subfamily of Platygastridae, but the classification has been revised based on molecular and morphological evidence.

[2] Sceliotrachelinae includes the genus Aphanomerus, which includes a number of species:[3][4] Aphanomerus pusillus, a wasp native to Queensland, Australia, has proven effective against the "pandanus planthopper", or Jamella australiae, which has decimated populations of Pandanus tectorius along the coasts of northern New South Wales and Queensland.