Heliaeschna crassa Kr├╝ger, 1899

Family: Aeshnidae
Scientific Name: Heliaeschna crassa
Common Name: Nighthawker

Another very rare hawker species that can be found in Singapore, H. crassa inhabit swampy forests and are crepuscular in it’s natural habitat.

This was my 3rd sighting of this species, at the dense under-story of Upper Seletar Reservoir.

Compare to H. uninervulata and other Gynacantha Sp., H. crassa is far more elusive and also sensitive even to the slightest movements.

I am only able to capture a glimpse of this individual and a few shots before it disappear into the surrounding vegetation.

H.crassa -male. perching on a plant’s stem about 1.5 metre above the ground.
An older male with part of it’s upper right wing missing.
Unlike H.idae, H.crassa has it’s anal appendages slightly recurved.

Female of either H. crassa or H. idae has been photographed before in Singapore but I have yet to encounter any female species.


Heliaeschna uninervulata (F) Martin, 1909

Family: Aeshnidae
Scientific Name: Heliaeschna uninervulata
Common Name: Lesser Night Hawker

Heliaeschna uninervulata aka lesser Nighthawker in the local context is considered to be very rare in Singapore. I have sighted this species a couple of times especially at the Central Catchment Nature Reserves.

The current female species is sighted outside the nature reserve at a place I frequently explore for Gynacantha sp. such a G.basiguttata and G.dohrni. I am quite surprise to find this species over there as my impression is that this species prefers pristine forest with running streams nearby.

Nevertheless I am more than happy to have captured this species again – my third female’s encountered.

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At a glance the female is considered to be quite small in size, compared to H.crassa.
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The wings are clear and the appendages are still intact.
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Abdomen is dark brownish with dark flecks and patches.
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Notice the very striking greenish yellow eyes and olive green thorax.
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Here the single crossvein at the base of the wing median space can be seen.
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The visibly astonishing yellowish lower eyes and nice greenish thorax coloration is amazing.
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A glimpse of the female reproductive organs.

I believe this species is quite widely distributed in Singapore as I had bumped into this species at no less than five occasions, all at different locations. The Central Catchment Nature Reserve is the best place to observe this species.