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horace2264
29-Jan-2012, 03:54 PM
I went to the Belukar Trail around noon, and encountered these two skippers on a grass patch next to the trail. First one looks a bit like the Small Branded Swift, but it is larger and seems to have one or two extra spots. :thinking:

The second one should be Potanthus trachala (Detached Dart). :thinking:

Dr Seow, please advise on the species ID of these two skippers. Thanks. :)

Psyche
29-Jan-2012, 04:45 PM
No doubts about it this time. No. 2 is Potanthus trachala. The little overlap of spot 4 & 5 with the subapicals & spot 3, the deeply indented margins and the dark spots are obvious.
I was caught out with Brian's pics because I thought it was a small skipper and had mentally blocked out P. trachala.

One is much more exciting.
I believe this is Pelopidas agna. It is a larger species.
P. mathias has a strong grey tinge to the ochreous ground colour making it appeared dark.
However it will be necessary to check the upperside for confirmation.
It is not considered rare, and feed on the same grasses.

TL Seow:cheers:
Typical P. mathias female.
http://2.bp.blogspot.com/_0EK80AsaR7g/TDUoF9HP41I/AAAAAAAADGc/KDeU-m3x_w0/s400/DSC4912-SB-Swift.jpg
Typical P. mathias male
http://2.bp.blogspot.com/_0EK80AsaR7g/Sp0KsVFlSkI/AAAAAAAABiQ/uHcOWUhy1Zg/s400/DSC1375SBS-Skipper.jpg

horace2264
29-Jan-2012, 09:48 PM
Thanks, Dr Seow for the speedy reply. :)
The Potanthus specimen is bigger than the usual Lesser Dart (P. omaha) that I see.

For the first skipper, I happened to have a chanced shot of its upperside when it jumped at the flash. The two attached pics show the skipper with wings closed and opened at two consecutive shots. Are the upperside marking and the brand good enough to nail the ID?

Psyche
29-Jan-2012, 10:34 PM
Thanks, Dr Seow for the speedy reply. :)
The Potanthus specimen is bigger than the usual Lesser Dart (P. omaha) that I see.

For the first skipper, I happened to have a chanced shot of its upperside when it jumped at the flash. The two attached pics show the skipper with wings closed and opened at two consecutive shots. Are the upperside marking and the brand good enough to nail the ID?

It certainly is and what a surprise.
The male brand reaches vein 1b closer to the wingbase than the termen.
So it is P. mathias after all.
What a disappointment.
It seems the colour difference are all down to lighting & setting.
Still a helpful note here, ie. the underside of P. agna should be evenly ochreous without the dark shading.

Les, looks like your other ?P. agna is P. mathias too.

TL Seow:cheers:

horace2264
29-Jan-2012, 11:41 PM
It certainly is and what a surprise.
The male brand reaches vein 1b closer to the wingbase than the termen.
So it is P. mathias after all.
TL Seow:cheers:
I am not sure whether the upperside shot could be used accurately to compare lengths of two line segments on the wing as the right forewing might not be all within the same focal plane of the camera at that time.

The wing base could be further away as compared to the termen from the focal plane. :thinking:

Psyche
30-Jan-2012, 12:31 AM
You have a point there. There is a perspective distortion here where the outer part of the forewing nearer the camera appear longer than the part towards the wingbase, looking along vein 1b.

So, it could still be P. agna.
Unfortunately there are too many confusing images on the net to make a proper comparison.

TL Seow:cheers: