Overview
Platygastrids
parasitise
the eggs of Coleoptera (beetles) and Hemiptera (bugs), or larvae of Diptera: Cecidomyiidae (flies) in their galls.
Description
Members of this family are minute to small wasps (0.5 2.5 mm) that have drastically reduced venation that is either completely absent or limited to a single short tubular vein. Like
scelionids,
they have geniculate (elbowed) antennae that are inserted close together, just above the mouth, and a metasoma that is often elongate and/or flattened. In addition, several genera have a horn-like structure on the first metasomal tergite that provides a recess for the hypodermic-like ovipositor, while one group has the first metasomal sternite expanded ventrally to house a partly coiled ovipositor.
Distribution
There are probably several hundred species of platygastrids in Australasia, but the vast majority are undescribed; only 26 are described for Australia and 14 for New Zealand.
Masner and Huggert (1989) provide a detailed synopsis of the family, a key to about two-thirds of the genera, and descriptions of several new genera from Australia and New Zealand, while Austin
et al.
(2005) provide an extensive review of the systematics and biology of the group.
Further information about the Platygastridae can be found in Austin, Johnson & Dowton 2005, Masner & Huggert 1989 and Masner 1993.