Dragonflies: Hemicordulia australiae

Damselflies Austroagrion cyane Austroagrion watsoni Austroargiolestes calcaris Austrocnemis splendida Austrolestes annulosus Austrolestes aridus Austrolestes cingulatus Austrolestes io Austrolestes leda Austrolestes psyche Coenagrion lyelli Hemiphlebia mirabilis Ischnura aurora Ischnura heterosticta Pseudagrion microcephalum Xanthagrion erythroneurum Dragonflies Anax papuensis Archaeosynthemis orientalis Austroaeschna ingrid Austroaeschna multipunctata Austroaeschna unicornis Austrogomphus guerini Austropetalia tonyana Austrothemis nigrescens Crocothemis nigrifrons Dendroaeschna conspersa Diplacodes bipunctata Diplacodes haematodes Diplacodes melanopsis Diplacodes trivialis Eusynthemis virgula Hemicordulia australiae Hemicordulia tau Notoaeschna sagittata Orthetrum caledonicum Parasynthemis regina Petalura gigantea Procordulia jacksoniensis Synthemis eustalacta Telephlebia brevicauda
distribution map
Source: ALA

♀ Emerald, VIC

♂ Mitchell River NP, VIC

♂ Yuraygir, NSW
more
Common NameAustralian emerald
FamilyCorduliidae
Genus/SpeciesHemicordulia australiae (Rambur, 1842)
Abundance &
Distribution
Found throughout Australia and moderately common from Melbourne to Brisbane but rare in the tropics.
HabitatFound at a variety of still and sluggish water, preferring still water with abundant aquatic or emergent vegetation in forests.
Description &
Identification
These are medium-sized dragonflies, usually with green eyes (sometimes brown) and body coloration and pattern typical of "emeralds" — predominantly black along the top of the abdomen but with yellow markings curved up on the side. The black markings appear somewhat metallic and reflective and may appear greenish (hence their common name of emeralds). The side of the thorax for most emeralds is predominantly yellow with two or three dark, diagonal bands. The abdomen on males is thicker in the middle while for females it is thick at the base and evenly tapered to a thinner end.
Similar SpeciesVery similar to Hemicordulia tau from which it can tentatively be separated by having dark pterostigma and wing veins on the leading edges where H. tau has these in yellow. Definite identification can be made by viewing the coloration on top of the frons ("nose"); H. australiae has an indistinct dark patch while H. tau has a distinct inverted "T" shape. In the northern half of Australia there are several other Hemicordulia species but the patterns on the abdomen (tail) are noticeably different. Hemicordulia emeralds are also somewhat similar to Procordulia (swamp emeralds) that however lack the upward curving yellow markings along the tail.
Behaviour &
Observations
Males will patrol around water, typically flying continuously around half a metre above the surface and periodically hovering. They perch hanging vertically from vegetation or sometimes near horizontally when attached to a more sturdy object. Like all the emeralds, after mating the pair separate and females oviposit in flight, dipping their tail briefly into water.
LinksBrisbane Insects

Page Updated: 31-Mar-2016
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