50. Orthetrum luzonicum (Brauer, 1868)

No: 50 / Family: Libellulidae / Genus: Orthetrum

Name: Orthetrum luzonicum / Slender Blue Marsh Hawk*

Habitat: Ponds, Marshes, Streams and Rivers (Uplands and Lowlands)
Province(s): Widespread
In flight: April-October / Sightings (by me): Locally common

Easily confused with: Orthetrum glaucum

*I have adapted the name from 'Slender Blue Skimmer' to match the other species in the genus known in Thailand.

50 species now posted on my blog and a great species too!!!

Another Orthetrum species that is often confused with another species is Orthetrum luzonicum, commonly known as the Slender Blue Marsh Hawk. It is often miss identified with Orthetrum glaucum. However, it is quite easy to spot the difference. Simply look at the eyes. The eyes of Orthetrum luzonicum are a vivid blue/green colour and O. glaucum's eyes are dull in comparison. 

The Male

 The male's thorax and abdomen are bright powdery blue and S9-10 can be black, though I have seen specimens where this turns blue too. The males also have slight yellow/black markings on the abdomen, which seem slightly variable depending on age.

Those Eyes...

This is by far and away the easiest way to differentiate the species.

In Hand...

This one I captured with my little net. They also seem slightly smaller than most other species in the genus, though this could just be my imagination. Still, a beautiful little thing. When I released him, he flew straight towards another male and began fighting. 

The 'Young' Male

This young male, has a pruinosed abdomen, but only part of its thorax has changed.

The 'Mature' Female

Like the male, the female becomes pruinosed. This one I saw a good distance from the water's edge. The female also has a slimmer abdomen to its counterparts (from what I can make out anyway).

The 'Young' Female...

At last I spotted the female. it's actually similar to the young male. The thoracic markings are different and the eyes are similar in colour to that of the male, making it easily identifiable. Also, unlike other females in the genus, when you move near them, they only seem to fly to another leaf or twig. Whereas, other females fly away, never to be seen again.

The Copula

This is an odd one as it seems that they have finished the 'action' and are now in rest mode... maybe the bloke will have a cigarette!