Wednesday, 29 December 2010

Monkey Puzzle Pupa Emerging

Its been ages since my last post and I apologise for that once again. However, do expect posting to remain sporadic as I now have a job and have moved to city limits, with little time or access to wildlife and nature. However, I do have an accumulated backlog of images which I will try to post regularly. This is one such post.


I have posted earlier about the attractive Monkey Puzzle butterfly. Since I first saw the butterfly with its larva on the Ixora plant, I have been trying to catch its pupation and emergence. Although I haven’t succeeded with the first bit, I have been able to catch the latter half – the emergence of the imago from its pupa.


The pupation lasted more than a week with the pupa attached to the underside of the leaf of the host-plant.


The pupa is attached to the leaf by means of its cremaster at its tail end as well as a suspension loop, which is a nylon thread drawn over and across its dorsal side.


During the many hours I waited for the pupa to emerge, the only interruptions in its motionless stance was an odd visit by an inquisitive ant!


Finally, almost rapidly, the pupa broke open and the butterfly started to emerge with a real sense of urgency.


Once the anterior end was split open, the butterfly head popped through along with its feet.


The Imago then pulled itself free off its pupal casing using its feet and started to ascend the stem of the Ixora plant.


This is in contrast to the Grass-yellow butterfly, in which the imago rested on or near the pupal casing.


Even as the imago crawled upwards, blood appeared to be pumped into its wings, allowing them to be stretched open.


It continued to ascend upwards, perhaps to reach a more airy location in order to catch the breeze to allow its soft body parts to harden.


The Imago then stopped on a leaf tip and further began to expand its crumpled wings.


The expansion process is slow and is barely noticeable. However, you can see the difference in successive photographs.


When the wings were almost fully unfurled, it proceeded to move further upwards…


…and found a favourable, concealed location where it rested for nearly an hour sitting upside down before abruptly flying off to start its life as an adult butterfly.