Showing posts with label Tailed Emperor. Show all posts
Showing posts with label Tailed Emperor. Show all posts

Saturday 10 February 2018

Tailed Emperor emerged

The first of the Tailed Emperor butterflies emerged from its chrysalis today. When I checked on them at 1130 in the morning, this one, the first to set, had begun to show the adult butterfly colour beneath the case. The 'fur' of the thorax and abdomen and the wings spots can be clearly seen. I had been checking them every day and this one had turned straw-yellow yesterday.

I went to set up the time-lapse camera, only to find that it had not been emptied and re-charged so I had to do all that. Meanwhile, by the time that was done, about one-o-clock, the butterfly had just fully emerged. So it had taken less than an hour and a half to emerge. I had thought I still had time to set up, oops. I will be ready for the next one.

About twenty minutes later the butterfly turned around and continued to stretch.

To think that this marvelous, delicate form of life had been squashed into that tight case for the past 19 days. And it had been in a much more simple form of a caterpillar before that.

What a chance to see immaculate insect wing-scales. Not a single one missing or torn.

I think this butterfly was a female as it had an almost-all-white body and its tail was broad-ended. Here she extends her proboscis for the first time, stretching it through the leaves.

Then, this is her retracting his proboscis drawing in a tiny drop of water from the leaf surface. Her very first drink.

An emperor's tail - absolutely perfect.

A few minutes later, she was warmed up and flew off over the garden.

Gone.


Wednesday 24 January 2018

Metamorphosing into chrysalides 


A Tailed Emperor Charaxes sempronius Caterpillar curls up in preparation for metamorphosing into a chrysalis - the final stage before it then metamorphoses into an adult butterfly. (See the previous posts for further details on my watch of these caterpillars)


I counted seven caterpillars on the host food plant, a Persian Silk Tree, and as I watching them over the days, I noticed that the first had disappeared a few days ago. So I traced the branches, looking for any wanderers. I first found one crawling swiftly along a branch, heading away from the leaves where it had grown, and probably where its egg had been laid. I measured its pace and was surprised that it was travelling at 20 m per hour. Not bad for a 6 cm long caterpillar. This is probably the most vulnerable stage in its life as it was exposed, with no camouflage while on the bare branches and predatory birds could easily spot it if I could. I found three, and one was still feeding, so where were the other three. Had they found a secluded spot or had they been eaten?


Once they had selected a suitable spot to settle, they fixed themselves by the a specialised hooked organ, called a cremaster at their tail end, to a silk pad they prepare on a branch. Then they hung down on it, and kept wriggling in a curled position to begin with.

Hours later, they let themselves go and hung down straight. This is when they begin to metamorphose.


However - all three of the ones I could find changed into their chrysalides overnight. I set up a slow-motion camera on two of them, but that only worked in daylight. By morning the chrysalides were almost fully formed. The shot above was taken late in the evening. The shot below, of the same animal, was taken next morning. The leaves of the tree close up at night and open by day.


The chrysalis forms inside the old skin of the caterpillar, and when ready, it breaks through the back of the skin. The old skin is then wriggled up to the tail end where it dries and is shaken off. All is complete. I shall now wait about two weeks and try to capture the emergence of one of the butterflies from a chrysalis in slow-motion time-lapse.

Wednesday 17 January 2018

Tailed Emperor Caterpillars


As summer has warmed up and butterflies have become more abundant in the garden I have been watching for Tailed Emperor Charaxes sempronius females visiting or laying eggs on the Persian Silk Tree in the garden. I found a hatched butterfly there last year, so wanted to see any caterpillars.

See: the adult here

I haven't seen any butterflies yet this year, but at least one has laid eggs while I wasn't watching. I found chewed leaves the other day and I have been out at night watching the caterpillars since. They are mostly nocturnal feeders. Although I did see one feeding at about 1100 hr one day.


There are six of these caterpillars on the tree at the moment and they are all at this large stage. I never noticed any chewed leaves when they were small yellow instars.


There are many species of caterpillar which adopt defensive postures, curl up, or drop off their branch whenever they are approached by a potential predator, like me, but these didn't do that. They simply carried on eating or walking along a branch while I watched them. The four pairs of prolegs on the abdomen can be clearly seen in this photograph, with the pair of claspers on the last tail segment. The prolegs have tiny, tiny hooks on their tips for hanging onto vegetation.


Their heads are adorned with these marvelous horns. I watched an ant wander close to one and it faced it off, presenting its horned head-plate at the ant, tracing its path as it passed. Not that the ant probably noticed, they follow scents more than vision. But the horns might deter bird predators. And what are those two little horns in the centre. Anyone know?


In this photograph one pair of the true legs on the thorax can be clearly seen, they are segmented with little claws on the end. This caterpillar carried on munching as I clicked away, its mandibles chomping sideways at the leaf with quite astonishing speed and efficiency.


Once they have fed enough, they crawl back along their branches to pre-formed beds. These are silken pads spread on a leaf, or used to hold two or three leaves together. The silk is sticky, and firm on the leaf, and the caterpillars can hold onto it easily. This is important to help the caterpillars stay attached to the leaf when the wind blows. For they certainly bounced about one windy day when I was watching them. They held on effortlessly.



And there they sleep and grow for much of the rest of the night and most of the day, curled up safely camouflaged and with a firm grip of their leaf bed. Isn't it amazing what goes on in the garden.

Saturday 18 February 2017

A spectacular garden butterfly

Tailed Emperor Polyura sempronius


This magnificent butterfly was just outside our house yesterday, well it emerged yesterday, but as a caterpillar it had been in the garden for long before that. I never knew.

Hiding in the leaf litter at the side of the yard


I noticed it as it fluttered away from me when I was in the yard, and I could tell it had only recently emerged from its chrysalis as it was weak, only scuttling across the ground and into the leaf litter lying at the base of a wall. It looked so vulnerable as there are lots of birds in our garden and it would have been easy prey if any found it. So, as it was evening I took it inside for the night, lifting it by the feet, careful not to damage its scales. It was in lovely fresh condition.

In the evening I did a bit of research.

The splendid double tail on each of the hindwings - with lovely fresh margins and scales


After a good night's sleep I took it back into the yard and offered it a split grape or a chunk of pineapple for breakfast. It chose the pineapple, well these butterflies love their fructose. After a good long sip of juice it began to shiver to warm itself up. The sun was still hidden behind some trees.

Pineapple for breakfast


Then when the sunshine came through, I popped it onto the sunny side of the tree which it had been living on when a caterpillar, a Persian Silk Tree Albizia julibrissin. It immediately lined itself up so that its back was warmed by the sun through a thin gap between its closed wings. The previous night had been cold, so it took an hour or so of sunshine to warm up and begin to shuffle about. Every now and then, it shifted slightly to stay aligned with the sun.

Lined up to capture the sun's heat on its back


While I was waiting for the butterfly to take off safely, I kept close by, keeping potential predators away, and I had a bit of look through the branches of the Silk Tree. Sure enough, I found lots of nibbled leaves, and a recently emptied chrysalis.

Tailed Emperor habitat - the Silk Tree is above and left of the table


The chrysalis was like the tiny beginnings of a wasp nest, except that it was not paper, but keratin I suppose, and see-through as it was empty. I couldn't find any others, nor any caterpillars. I shall go out for a look after dark.

The chrysalis it emerged from, hanging empty from a small branchlet of the Silk Tree
- attached by a tiny silk button


Meanwhile, as the butterfly was keeping so still I took lots of photographs. I sent a set of shots to Suzi Bond, our local butterfly person and it was she who identified it as a female by her white abdomen and large size, with a wingspan of over 80 mm.

Her gorgeous face - her eyes had a black pearl effect, her proboscis was curled tight into her 'fur' and her labial palpi, a pair of  olfactory sensory organs, pointed up like a snooty nose


That was a very pleasant morning. I had learned a lot, and taken some curious shots of the butterfly, her face and wing pattern.

On recall, during the waiting, I had seen the leaves eaten in previous years, even found a spectacular green, horned caterpillar beneath the tree before, but I had not found time to identify it properly.

I left her to sun herself on her larval food tree, but once warm enough, she fluttered down to the ground and sat there motionless in the leaf litter. She obviously felt safer there where she was camouflaged.
I had found her in her favoured resting habitat.
 I'll watch the Silk Tree more thoroughly in future, and the ground below.