Wednesday, July 20, 2011

Damselfly (26a) - Dysphaea Dimidiata

Family : Euphaeidae
Common Name : Black Velvetwing
Status : Extinct
Location : Gunung Belumut Recreation Forest

Dysphaea dimidiate is a large damselfly species, classified as extinct in Singapore. The males have dark purplish colour on its body and half of its wings but when seeing it from afar, it looks more like a black damselfly. The females are said to have brownish yellow marking on its thorax and they are rarely sighted in open areas. The males are normally found perching on rocks, branches or falling logs in clear forest streams. When doing a search in the internet, I could find a handful of male images but not a single image of the female.

My first sighting of a male was at Endau Rompin in August 2010. My impression then was that it is a skirtish species but when we spotted it recently at Gunung Belumut Recreation Forest, it was fairly cooperative. Most of us managed to get some decent shots. I notice that the male likes to perch under hot sunlight. It would, sometimes, open and close its wings while perching as if to suntan its wings. When doing so, it really looks a little like a true dragonfly.

The female D. dimidiata was on my wishlist since last year but what I saw was totally unexpected. A female came from nowhere and suddenly my photography buddy suddenly shouted with excitement “Hey, they mate!”. I turned around and I saw the mating pair perching on an unattractive fallen branch not too far away from me. The lighting was harsh but guessing that the mating may not last long, I did not bother to get something to block the strong sunlight. True enough, the mating lasted only about 3 minutes.

(A rare mating sight)

(The male opened and closed its wings even during mating!)

After the female's anal appendages separated from the male's genitalia, the male pushed the female under the water of a nearby floating log as shown below:

(Male pushed the female under the water)

Thereafter, the female submerged under the water for about 3 to 4 minutes to ovipositing while the male stayed  above the log to guard from any disturbance by rival males.  It is quite common to see female laying eggs above the waterline or at the waterline but this is the first that I saw egg laying below the waterline!  Truely amazing!

(Female laying eggs under the water)

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