A widespread and common family of dragonflies which includes several endemic higher-level taxa. Many species are brown or black with yellow/green markings. Adults can be readily identified to family by features of the wing venation, but separation of larvae between Corduliidae and Libellulidae can be difficult. It may be that the boundary between these two families is poorly defined.
Corduliid and Libellulid larvae are short and rounded. The labial mask is strongly concave and covers the whole front of the 'face'. The palps are much broadened distally and carry setae, either singly or in discrete bundles.
The labial palps in Corduliidae are toothed or notched distally (except in the first free-living (2nd) instar (John Trueman, pers. obs.) where that instar is known). Those of Libellulidae generally remain distally smooth throughout development. In those Libellulidae where the distal edge of the palps become notched in later instars, the anal pyramid is long with three long points (epiproct and paraprocts) and two shorter spines (cerci). The anal pyramid in corduliid larvae is generally short with all five points of equal length.
NB : A recent guide to the larvae of Australian Odonates (Hawking & Theischinger, 1999) has proposed a new classification system in which the family Corduliidae has been divided into the families Synthemistidae, Gomphomacromiidae, Pseudocorduliidae, Macromiidae, Austrocorduliidae, Cordulephyidae, Oxygastridae, Hemicorduliidae and Corduliidae.
Hawking, J.H. (1986) Dragonfly larvae of the River Murray system. Albury-Wodonga Development Corporation Technical Report No. 6., Wodonga.
Hawking, J.H. and Theischinger, G. (1999) Dragonfly Larvae (Odonata): A Guide to the Identification of Larvae of Australian Families and to the Identification and Ecology of Larvae from New South Wales . CRCFE Identification Guide No. 24., Cooperative Research Centre for Freshwater Ecology, Thurgoona.
Theischinger, G. and Watson, J.A.L. (1984) Larvae of the Australian Gomphomacromiinae, and their bearing on the status of the Synthemis group of genera (Odonata: Corduliidae). Australian Journal of Zoology 32 : 67-95.