Saturday, 9 May 2009

Tholymis tillarga

Anisoptera
Species name: Tholymis tillarga
Family: Libellulidae
A male resting in the shade during the day photographed 
on Pulau Sapi an island off Kota Kinabalu  

This is another common crepuscular libellulid like the two Zyxomma ssp. (obtusum & petiolatum) and are found in similar habitats, i.e. drains, weedy ponds and other open bodies of water. 
Two males in flight at dusk

It is active at dusk, flying to and fro along drains and across ponds, the males are quite conspicuous for the white wing patches. In flight they are rather frustrating to photograph! 
An immature male showing very faint white wing patch

A female

The body of this medium-sized insect is orange-brown and the hindwing has an amber tinted patch followed by a patch of bluish white in the males while this white patch is absent in the female. Hence its common name - Coral-tailed Cloudwing.

Distribution: widespread in tropical Asia, Africa and Australasia.

Sunday, 3 May 2009

Drepanosticta versicolor

Zygoptera
Species Name: Drepanosticta versicolor
Family: Platystictidae


Members of this family of small damselflies are dwellers of primary dipterocarp forest and found on small streamlets and boggy areas around springs. Drepanosticta spp are brownish bronze in colour, usually with abdomens marked sparingly with light blue or pale spots and they fly close to the ground in the shaded  forest understorey making them very difficult to see. I only saw this specimen for a few moments before it vanished back into the shadows!

Bornean platystictids are still not well studied and many more new species are likely to be found. However the insect in my photos is quite likely to be D. versicolor by virtue of the presence of a long sharp spine on the rear margin of its prothorax. (I thank Dr Rory Dow for identifying these, and other photos for me).

I took these photos on a recent visit to the Danum Valley Field Centre whose many jungle trails and streams proved to be ideal hunting grounds for me! Alas two days was simply too short!

Saturday, 2 May 2009

Coeliccia nigrohamata

Zygoptera

Species Name: Coeliccia nigrohamata

Family: Platynemididae


I found several males of these small damselflies with conspicious blue markings on the upperside of the thorax resting on low vegetation along a small streamlet on the forest edge in the Danum Valley Field Centre. Unlike most damselflies they were extremely unafraid and I could easily pick them up with my hand. (Unfortunately I did not see any females).

On checking Dr A G Orr's Dragonflies of Borneo later I found my photos matched that of Coeliccia nigrohamata. I was however informed that members in this group of Coeliccia were currently under reclassification and this could very well be classified as a different species! 
Coeliccia spp. are found in forested habitats, inhabiting fresh water marshes, streams and springs. They are not usually found in open country or big rivers. This particular species belongs to a group of blue-marked species in the genus, another group consists of mainly species with yellow markings. A species found in Peninsular Malaysia, C. octogesima has a famous blue telephone-shaped logo on the synthorax (see Dr Choong's blog).

Coeliccia nigrohamata  has been recorded from Brunei and Sabah.

Saturday, 25 April 2009

Neurobasis longipes

Zygoptera
Species Name: Neurobasis longipes
Family: Calopterygidae

Male on rock in midstream (taken without flash)
This  surely has to be the most beautiful damselfly in Borneo! Witnessing it in nature is one of the most breathtaking experiences for me. My photos hardly convey the true beauty of this creature that has simply to be seen in life.  I had previously only glimpsed it momentarily on a few ocassions in forested rivers and had never had a chance to photograph it until now. 

Close-up of male (taken with flash)
I saw this spectacular male in the shallow rocky Sungai Palum Tambun which is a tributary of the mighty Segama River in the Danum Valley Field Centre. It was tirelessly flitting from rock to rock in the late afternoon, occassionally I also saw his less colourful mate, but she was too shy to pause and pose for me! It had me chasing it from rock to rock trying to get a good picture and mercifully, just as I was about to become totally exhausted and before the sun disappeared, it stayed put for a while and let me approach it to get my photo!

The body of both sexes are bright metallic green in colour, the top of the male's hindwings are brilliantly iridescent  green and its forewings are clear with a yellow-brown tint while the both the female's wings are clear with a lighter yellow-brown tint.

Members of the family Calopterygidae (from the Greek words meaning beautiful wings) are slender with long thin legs and mainly coloured metallic green. N. longipes is found in Borneo as well as in Peninsular Malaysia where another similar and slightly bigger species N. chinensis is also found. 

Sunday, 12 April 2009

Orchithemis pulcherrima

Anisoptera
Species Name: Orchithemis pulcherrima
Family: Libellulidae
I was pleasantly surprised when I came across this small dragonfly near a pond in the oil palm plantation recently as I have never seen it in Sabah before. I first saw and photographed this species in the Lambir Hills National Park in Miri, Sarawak in 2006.
This species is rather interesting because of its many colour forms or morphs. At least four distinct colour forms are known - orange, red, blue and a dark almost black form with a white band on its abdomen. 
This male, like the one I saw in Miri is of the orange variety.

The geographical range of this libellulid is recorded as Vietnam, Thailand, Peninsular Malaysia and Singapore, Borneo, Indonesia and the Philippines.

Sunday, 15 March 2009

Raphismia bispina

Anisoptera
Species Name: Raphismia bispina
Family: Libellulidae

Female

Last week on a short visit to the Borneo Paradise Eco-resort near Lahad Datu, Sabah I saw and photographed a small female libellulid on the mangrove edge which I had never seen before. When Rory Dow saw the photo which I emailed to him he said it looked like the female of Raphismia bispina a mangrove specialist. On checking the books and on the Net I found out that the male is a small blue fellow that resembles Brachydiplax chalybea, and I suddenly recalled seeing what I thought was a very skittish B. chalybea at the same place.

Male guarding a pond

Well, today I went to look for this male and found quite a few of them in the mangrove forest at the resort. Almost every small tidal pond (of salt water) has at least one male guarding it. And I also saw a female ovispositing in one of the ponds jealously guarded by the resident male.

Male perched on mangrove seedling

At first glance the males look like B. chalybea except that they are a bit smaller and the shade of blue is slightly different. But unlike the latter they are very skittish flying away at the slightest movement and landing further away. It took me quite some time and very patient stalking to get my first satisfactory shot.

I also tried to take some photos of their underside (upskirt photos!!) to try to show the signatory twin spines on their thorax behind the hind legs and the process projecting beneath on segment 2 of the abdomen. See if you can spot these on the photos.

Male, the process on abdominal segment 2 is clearly 
visible, but the pair of spines behind legs are less so

Sunday, 1 March 2009

Zyxomma petiolatum

Anisoptera
Species Name: Zyxomma petiolatum
Family: Libellulidae

Male

Two species of Zyxomma are quite commonly encountered but are rarely noticed because they are both crepuscular, i.e. they are active only when the sun has set and before sunrise. Z. petiolatum are less often seen or noticed because of its sombre brownish colour, unlike the male Z. obtusum which is covered in a "ghostly" white pruinescence that extents to its wings. 

The two Zyxomma species are very dissimilar, with obtusum being more "libellulid-shaped", while the petiolatum male has a long and very slender abdomen; the female's is somewhat thicker.

Both sexes are active from late afternoon to well into the evening and probably at dawn too as with obtusum, and are attracted to lights; the photos here are of specimens that flew into the house at night.


Female

Said to be widespread in tropical Asia and Australasia.