Monday 24 August 2020

Zyxomma obtusum 2



Anisoptera

Species name: Zyxomma obtusum

Family: Libellulidae  

Mature males of this crepuscular species are entirely covered with white bloom which gives it a ghostly appearence when silently flitting over drains at dusk or early dawn.
 
A male in flight. See another male in flight here


I recently found some larvae living in a cement water tank, no doubt feeding on tadpoles of the four-lined tree frog and other aquatic life in the water.

A final instar nymph.

A nymph that has crawled out of the water and 
ready to emerge.

The newly emerged imago beside its exuvia in the process of drying its wings.
 It is a male (teneral) still lacking its full mature colour. 

Friday 7 April 2017

Sieboldius japponicus


Anisoptera


Species name: Sieboldius japponicus

Family: Gomphidae

The first time I saw this species was on a boat ride on a clear rocky forest stream in Long Pasia, Sabah in September, 2016. To my astonishment one flew past our boat as my friend Shauming Lo and I were just beginning to take in the beauty of the surroundings. It was large and flew quite audibly and was like nothing we had seen before. Shauming promptly nicknamed it The Helicopter! We quickly scrambled to take photos of it when it perched on the side of the boat, but when we met more and more along the way we took our time and were able to take some photos of them on rocks and wood in the river.






With a hindwind length of 55mm in males and up to 57mm in females it is the largest of Borneo's gomphids. Its colour and rather small-headed appearance also make it easy to recognise.

Though its name "japponicus" may seems to indicate that it is also found in Japan it in fact is only present in Borneo, Sumatra, Malaya and southern Thailand. It was named in 1854 on the mistaken belief of the author that the specimen was collected in Japan!

Tuesday 4 April 2017

Brachygonia oculata


Anisoptera

Species name: Brachygonia oculata

Family: Libellulidae



Even though described as widespread and common in its range I only recently encountered this dainty species in the Sama Jaya Nature Reserve in Kuching, Sarawak after years of semi-serious dragonfly chasing! The males (I did not see any females) were gathered in quite large numbers in the swampy area of the park and were quite conspicuous in their attractive powder-blue and orange "attire". After I saw the first one it was very easy to see one everywhere I looked along the forest paths!

The species' range is Sundaland (except Java) up to Indochina. 




Tuesday 4 March 2014

Rhodothemis rufa

Anisoptera

Species name: Rhodothemis rufa

Family:   Libellulidae


My last post on this species was in December 2009 featuring a newly emerged female. Male R. rufa is not easy to distinguish from other medium-sized red species of libellulid like Orthetrum testaceum, Crocothemis servilia or Urothemis signata. The female however is easier to recognise with her brownish colour and a middorsal pale yellowish streak.

I have recently photographed both males and females in the field.


Male
Female

Tuesday 1 January 2013

Pantala flavescens - Emergence


Anisoptera

Species Name: Pantala flavescens

Family: Libellulidae

Without realizing it two long years had passed since my last post! My first post for the new year 2013 is only my second "emergence" post - of arguably, the most common dragonfly in the world.


In December 2012 I was lucky to find a few nymphs in a water tank and one night literally stumbled on an emergence in progress.



















Sunday 12 December 2010

Trithemis aurora


Anisoptera
Species name: Trithemis aurora
Family: Libellulidae

A whole year has passed since I last posted in this blog! I just can't believe how time passes so fast! Well, at least I still have one post in 2010. Hopefully more...

Male in all its splendour
Female

The Crimson Dropwing is a common dragonfly of open ponds and drains. The male is brightly coloured - its whole body as well as the viens on its wings are bright pinkish crimson. Quite a sexy guy, who likes to show off his colours basking in the sun while assuming the obelisk posture! The female however is comparatively dull - she's light brownish.
Male in obelisk posture

Female doing handstand! What he can do so can she!

This is a widespread species with a geographic range that cover the whole of Asia.

Sunday 20 December 2009

Rhodothemis rufa

Anisoptera

Species Name: Rhodothemis rufa

Family: Libellulidae


For the first time I was able to rear a dragonfly larva up to emergence. However unfortunately although I guessed the day of emergence, I was too late to catch the start of the emergence process.On the morning of the larva's change to adulthood I woke up at 3:15 a.m. but found that it had already fully emerged! I was only able to take photos of it hanging fully extended from the exuvia.

This, after 2 months of guessing and wondering about its species, turned out to be Rhodothemis rufa a common species in Asia - with a range from Bangladesh through India, Indochina, China, Malaysia, Indonesia and the Philippines. My thanks to Dr Rory Dow and Dr Sadayuki Ugai for the sp. identification.

The male however is rather difficult to distinguish from other common and very similar red libellulids. However the female (shown here) is recognized by its brownish colour and the mid-dorsal light yellow streak which run from the top of the antefrons through the thorax down to segment 5 of the abdomen. Unfortunately I don't have a photo of a male.

The larva when I first collected it was a rather long-legged spiderlike creature!

Mature larva (underside)


Mature larva with mosquito larvae which I provided it. It also readily ate small tadpoles.


The newly emerged female with its characteristic mid-dorsal line.