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Commander
15-Oct-2006, 03:11 PM
This initial shot of a male Eurema sp. shot on 7 Oct 06 at an open wasteland area in the northern part of Singapore, proved to be something different after all. Whilst hunting for the Tawny Costers, these abundant "Yellows" looked a bit different and hence a voucher specimen was taken for further scrutiny.

It was found to be a re-discovered Eurema brigitta senna, a species which had been missing from the Singapore Checklist (http://www.geocities.com/RainForest/Vines/2382/sgchecklist.htm) as it was not sighted until now.

Its host plant, Cassia mimosoides, is described as a "An exceedingly variable, prostrate to erect legume up to 1.5 m high, usually annual, sometimes with stems becoming woody above ground level and enabling the plant to perenniate. Stems variable, usually puberulent with short curved hairs, sometimes more or less densely clothed with longer spreading hairs. Inflorescence supra-axillary or sometimes axillary, one- to three-flowered. Pedicels 0.3 to 2.5 (3.0) cm long, usually shortly puberulent, sometimes spreading hairy. Petals yellow, obovate 4 to 13 mm long, 2 to 9 mm wide."

The host plant has also been described in "Keng, H. (1990) Concise Flora of Singapore"

So the conclusion is that this species, previously on the checklist in C&P4, has now been re-discovered by ButterflyCircle again! :gbounce:

Commander
15-Oct-2006, 03:21 PM
The physical characteristics of this species are quite unique and is easy to differentiate from the other "Grass Yellows" found in Singapore.

"The underside forewings are without cell spots. Upperside forewing black apical border serrated, but not more deeply excavated in spaces 2 and 3" - source : Corbet & Pendlebury Edn 4 page 98.

Females are slightly more unique in that the yellow colour of the hindwings are lighter than the forewings on the undersides, as can be seen in the photos below. The males' undersides are unicolourous as with the other species of this genus.

Confirmation specimens will be sent to FRIM in Malaysia to confirm the status of this species, which could also possibly be a unique subspecies of E. brigitta found here. Those specimens of E. brigitta found in Malaysia are known to be not as large as those that have been observed here, suggesting that it could also be a different sub-species. :thinking:

Sky Blue
15-Oct-2006, 03:27 PM
:cheers:

bell
15-Oct-2006, 03:38 PM
Congratz!!!! :redbounce

Peacock Royal
15-Oct-2006, 04:53 PM
Well done. Congratulations.
Many of us ignore the Yellows as they are so difficult to shoot. Now better keep chasing the Yellows.

Cruiser
15-Oct-2006, 06:18 PM
congrats! :cheers: :jumjoy:

Sky Blue
15-Oct-2006, 06:36 PM
yeah, update the good news in our home page!

horace2264
15-Oct-2006, 06:37 PM
Congrats for another +1 to the checklist.
This one really needs the sharp eyes of a master to spot and tell it apart from the common yellows. The other day I saw a mating pair of yellows with one of them having a much paler coloration, but I dismissed it as one of those variation cases and did not bother pursuing a shoot.

Horace

Sky Blue
15-Oct-2006, 07:10 PM
(tumpang yr thead on this butt)

The caterpillar of this species look different from the rest of Eurema with the distinctive black line at the back
http://butterfly.mingcolour.com/album/butterfly_forum/30_1160906226.jpg

Commander
15-Oct-2006, 07:30 PM
Interesting black stripe.... looking forward to the full life history in your nice format. :)

Common Rose
16-Oct-2006, 11:39 AM
congrats to another +1. :cheers:

Silverstreak
19-Oct-2006, 11:16 AM
SC, is the yellow stuff on the leaf the pupae?? If so it is very small....



(tumpang yr thead on this butt)

The caterpillar of this species look different from the rest of Eurema with the distinctive black line at the back
http://butterfly.mingcolour.com/album/butterfly_forum/30_1160906226.jpg

Common Mime
19-Oct-2006, 12:12 PM
I think that is some kind of bug?

The pupa is not like this.

Sky Blue
19-Oct-2006, 06:47 PM
it's pupa, but pupa of parasite wasp, if you observe in the field, you can see many of these yellow pupa case around the host plant esp near the later instar cats.

some cats collected from wild (not breed from eggs) tend to be parasited by wasp.