Overview
Megalyrids (long-tailed wasps) are thought to be
ectoparasitoids
mostly of immature stages of wood-boring Coleoptera (beetles), although one Australian species is parasitic on a mud-nesting pemphredonine wasp
(Crabronidae)
. Members of this family are rarely collected, but may sometimes be seen walking on the trunks of eucalypt trees searching for host tunnels.
Description
These small (2.5 mm) to very large (100 mm) wasps are characterised by having 14-segmented antennae; a bulbous head; subantennal grooves on the face (into which the antennal scapes fit); absence of a pronotal inflection or lobe so that the mesothoracic spiracle is exposed; large triangular axillae between the scutum and scutellum; lack of a pterostigma in the fore wing; and usually a very long ovipositor.
Females of the genus
Megalyra
can have ovipositors ranging from five to eight times their body length.
Distribution
Megalyrids are more diverse in the Australasian region than anywhere else in the world. The Australian fauna comprises 21 species of
Megalyra
. This genus is also represented by a few species in New Guinea, South-east Asia and New Caledonia, while a single species of
Carminator
also occurs in New Britain and the Bismarck Archipelago. The family does not occur in New Zealand.
Further information about the Megalyridae can be found in Mason 1993, Naumann 1991, Shaw 1990a and Shaw 1990b.