Overview
Aeshnidae are large, robust dragonflies, often with brown and yellow markings. The compound eyes cover the head and meet broadly along the mid-line. Species may breed either in still or running water and males often can be seen 'hawking' back and forth over suitable oviposition habitat. They also hawk along roads at windscreen height, much to their cost (cf. Corduliidae, in which males of
Hemicordulia
often hover over roads at radiator height). Females insert eggs into floating or submerged plant tissue and oviposition often takes place in tandem.
Two common and widespread still-water species are
Hemianax papuensis
and
Adversaeschna
(formerly
Aeshna
)
brevistyla
. These both belong in the cosmopolitan subfamily Aeshninae. A majority of the Australian fauna, eight endemic genera and 30 species, form part of the subfamily Brachytroninae. All but one of these species is restricted to the eastern states and most breed in streams. The median space is crossed in
Dendroaeschna
(1 sp.) and in the crepuscular
Antipodophlebia
(1 sp.) and
Telephlebia
(6 spp.). These last two have semi-terrestrial larvae. Adults of
Telephlebia
and
Austrophlebia
are immediately recognisable by a light brown bar along the costal margin of each wing.
Austroaeschna
(16 spp., 1 western) is the largest genus, and
Notoaeschna
and
Spinaeschna
each have 2 spp.
Acanthaeschna
and
Austrophlebia
are monotypic, tend to crepuscular behaviour, and are huge insects (span 120-150 mm).
Anax
(3 spp.), and
Anaciaeschna jaspidea
are aeshnine, not commonly recorded from Australia but with ranges to our north. They breed in still waters. The Gynacanthaginae, with
Gynacantha
(five dull-coloured, tropical spp.),
Agyrtacantha dirupta
(dull-coloured, Cape York, crepuscular) and the more brightly coloured and more widespread
Austrogynacantha heterogena
, inhabit still waters and may be seen (but not captured) flying high in the treetops at dusk. Aeshnid larvae are elongate and unmistakable.