Monday, July 26, 2010

Anax guttatus vs Anax panybeus - Anal Appendages

Anax guttatus and A. panybeus are quite similar to each other. In fact when I caught a specimen of A. guttatus a few years back, I labelled it as A. guttatus. My mistake was immediately pointed out by Dr. A.G. Orr when he inspected my specimen during his visit to Malaysia.

One important character to distinguish A. guttatus from A. panybeus is their anal appendages. The anal appendages of A. panybeus is more massive and larger than that of A. guttatus. Of course, the shape of anal appendages for both the species is also slightly different.

left is A. guttatus and right is A. panybeus

Larval Emergence of Neurothemis fluctuans

I witnessed the larval emergence of female Neurothemis fluctuans.

This larva (image above) was photographed at 14:30 hour. It is very matured, and it is going to emerge very soon......

After eight hours later around 23:00 hour, this happened (see images below)! Showing below are a series of three photos taking at the most critical moment - the whole adult insect is emerging out from the exuvia. This critical moment only took less than 5 seconds! In order to take record this critical moment with camera, one has to wait by the emerging larva patiently.

Saturday, July 24, 2010

Mortonagrion aborense - Immatured

The immatured Mortonagrion aborense has red colour, and it looks more appealing compared to the matured individuals..........

Thursday, July 22, 2010

Comparison: Anax guttatus vs Anax panybeus

Two Anax species are recorded in Peninsular Malaysia - Anax guttatus and A. panybeus. The anal appendages and the length of abdominal segment 3 are the main characters to differentiate these two species. However, I am showing you here the differences of blue marking on the thorax and dorsal abdominal segments 1-3 for both the species.

left: Anax guttatus; right: Anax panybeus

A Large Cordulid Larva

This large matured cordulid larva is living in my little aquarium..... Anybody wanna guess what species is this?

Wednesday, July 21, 2010

Finally It Has Emerged!

The aeshnid larva that I have been talking about (click here to see the larva at F0 stage) has finally emerged! This morning I saw the beautiful newly emerged adult aeshnid not far from the exuvia. It is a male Anax panybeus!

exuvia of Anax panybeus

newly emerged Anax panybeus

Sunday, July 18, 2010

Going to Emerge.............

This aeshnid larva measuring up to 55 mm from head to tail (really large) has been out of water in the evening for the last two days. Its wing cases have hardened, and it looks very mature. I'm sure that it is going to emerge very soon....... It is most likely an Anax guttutas..... I keep my fingers cross.

Tuesday, July 13, 2010

Odonata Checklist of Sg Durian, Perak

I visited Sg Durian, Lintang, Perak for second time a few days ago to survey the odonate diversity. I managed to add six more species to the previous checklist. Now the total number of odonate species recorded for Sg Durian is 30.

Odonata Checklist for Sg Durian, Lintang, Perak

Family Calopterygidae
Neurobasis chinensis
Vestalis amoena

Family Chlorocyphidae
Heliocypha perforata
Heliocypha biforata
Libellago lineata

Family Euphaeidae
Dysphaea dimidiata
Euphaea impar
Euphaea ochracea

Family Megapodagrionidae
Rhinagrion mima

Family Coenagrionidae
Agriocnemis femina
Argiocnemis rubescens
Onychargia atrocyana
Mortonagrion aborense
Pseudagrion pruinosum

Family Platycnemididae
Copera ciliata
Copera marginipes

Family Protoneuridae
Prodasineura humeralis
Prodasineura collaris

Family Gomphidae
Ictinogomphus decoratus
Paragomphus capricornis

Family Libellulidae
Aethriamanta gracilis
Brachydiplax chalybea
Neurothemis fluctuans
Onychothemis culminicola
Orthetrum chrysis
Orthetrum luzonicum
Orthetrum testaceum
Trithemis aurora
Trithemis festiva
Zygonyx iris

Pseudagrion pruinosum in Wheel

Lately, I had a chance to take some shots on a wheel pair of Pseudagrion pruinosum. In Peninsular Malaysia, it is hard to spot female of P. pruinosum though a good number of male may be present at the site. To bump into a wheel pair of P. pruinosum is something to be happy about, I guess.

A Close Encounter - Rhyothemis plutonia

Rhyothemis plutonia is a rare dragonfly species of Peninsular Malaysia. In 6-7 years of field experience, I have only spotted two individuals at two different locations. A few days ago, I had a very close encounter of R. plutonia (my second time to bump into an individual of R. plutonia). Of course, I made countless shots on this male R. plutonia. Taking photograph on black dragonfly is always a challenging task, and most of the photographs ended up as bad shots. Nevertheless, I did make some satisfied shots (on my own stadard :)).

Wednesday, July 7, 2010

I've Got the Answer

The aeshnid larva that I mentioned on June 6, 2010 has finally emerged! It is a male Gynacantha subinterrupta!

a larva of Gynacantha subinterrupta (male)

Tuesday, July 6, 2010

On Larvae.....

I mentioned a large larva on June 28, 2010 (click here to see the entry). The large larva has just shed it skin today. Now the large larva has well developed wing cases (see the photo below), and I believe that it has entered F0 stage. The large larva is now meausuring up to 52 mm from head to tail! Really large! The shape of the larva does look like the larva of Anax guttatus.

Anax guttatus larva?

I actually also caught a baby larva (10 mm) a few days ago. The baby larva is so cute (see photo below). It has white and dark segments - very unique. The shape of this baby larva resemble the large larva above.....

a baby larva

I also mentioned about another aeshnid larva (smaller one; see the photo below) on June 28, 2010 (click here to see the entry). This larva has been out of water for the last 3-4 days (even during day time). It is going to emerge tonight! I'm going to have the answer of its real id by tomorrow!

a Gynacantha larva?

Female - Pseudagrion australasiae vs Pseudagrion microcephalum

The male adults of Pseudagrion australasiae and P. microcephalum are very much alike, and normally anal appendages (tail) are used to distinguish them confidently (click here to see the differences between the male adults). How about female adults of P. australasiae and P. microcephalum? In fact the female of both species look alike as well. Of course, the size of P. australasiae female is slight larger than P. microcephalum female (the same case for the male adults). Nevertheless, a close look on the head and thorax of the female adults, one will find obvious differences between these two species. The female of P. australasiae has very obvious thick black strip on the dorsal thorax and the head lack of blue marking, but the black marking is very obvious. On the other hand, the female of P. microcephalum has narrow/thin black strip on the dorsal thorax and the head has blue marking.

female adult of P. australasiae

female adult of P. microcephalum