www.ukbutterflies.co.uk

Absolutely fantastic stuff and bringing back happy memories. You should now be able to calculate nearly to the day when L2 will emerge.

Oh, and keep an eye on L3, i'll expect it to go to ground tomorrow.

BTW, you should see L2 get stout and chunky and attach to the ground at the head end. Then the hairy skin peels back to rveal a shiny pupa with the aappearance of polished walnut venere. Gorgeous. Or perhaps not gorgeous and only a mother could love 'em but I loved my babies

Thanks for the comments Guy, this is a voyage of discovery for me as well.

Susie wrote:Absolutely fantastic stuff and bringing back happy memories. You should now be able to calculate nearly to the day when L2 will emerge.

Susie, I have no previous experience of this. How long after pupation would you expect hatching to occur?

Susie wrote:...you should see L2 get stout and chunky and attach to the ground at the head end. Then the hairy skin peels back to rveal a shiny pupa with the aappearance of polished walnut venere.....

Thanks Susie, I have noticed that some photos of the pre-pupation stage show the larva to be pink rather than brown. Should I be expecting this to happen next?

Vince

I would certain expect L2 to shed its skin over the next day or so. It is the right colour.

I can't remember how many days exactly, I will have to check.

40 days or there abouts. Keep your eyes peeled at the end of the first week of July!

Mind you, I am only going by what happened to mine last time, I guess if the weather is hotter or colder the time will vary.

Vince Massimo wrote:Susie, I have no previous experience of this. How long after pupation would you expect hatching to occur?

Susie wrote:40 days or there abouts. Keep your eyes peeled at the end of the first week of July!

First week of July? ............ Blimey!, that's early, but you could be right. The books say the eggs usually hatch between the end of April and the beginning of May, but L2 hatched on 10th April which is about 3 weeks early. I normally see my first adults in the last week of July, so this early (egg) hatching should result in a correspondingly early emergence. Watch this space..............

Vince

PS. We need a photo here because all the others are on the previous page

You dont need an excuse to put up photos as far as I am concerned. I love seeing them.

Mine started to pupate on 6 June 2009 and started emerging on 14 July so that's what I based my calculations on. I was told that mine pupated early because they were netted which caused a false micro climate which I expect is true, however I do know that the wild ones hatched out of their eggs at the same time as my netted ones so I think that brown hairstreaks emerge early in this area anyway.

Following the last posting, larva L2 settled down in the curl of a dry leaf in preparation for pupation. I did not disturb it but, was just about able to see that it had somehow attached itself to the roof of it's shelter. This morning, after 4 days of inactivity it finally pupated. When I looked into the leaf tube I could see that something had happened. There was a pale fuzzy mass at the rear of the larva which I initially took to be fungal growth, possibly indicating that the larva had died, but on closer inspection this turned out to be the old larval skin which nearly always remains attached to the pupa. Judging by it's appearance, pupation had only just occured and it was still somehow attached to the leaf, but I could see no silk.
Five hours later it had darkened-up.
The remaining two larva continue to feed and grow.

Vince

WOW!

I'm surprised it took so long to pupate and I am surprised that none of the others have yet either.

Stonking photos though Vince!

It's been a busy week with Orange Tip, Brimstone and Brown Hairstreak pupations, but the Hairstreaks have been the most enthralling. Checking the remaining two larvae this morning I found one of them (L3) down in the leaf litter at the bottom of the pot. It must have just descended because it was in it's transitional colour stage halfway between the old green and the new brown. Two hours later it had almost completly transformed to brown. Hopefully it will choose a more accessable place for pupation than L2. Meanwhile L1 continues to feed and, at 20mm long, is fully grown.
Although all were early to hatch from eggs the development of the larvae has slowed and there seems to be a pause between the end of feeding and pupation. It remains to be seen whether they will emerge at the normal time of the season.

Thanks for all the comments. I will continue to keep you all posted.

Vince

More news and observations to report.

Firstly, all of the larvae have now successfully pupated, albeit taking longer than expected. Pupation took place 6 or 7 days after the larvae left the foodplant. As a result I have now been able to establish the timing and sequence of events that lead to pupation. To begin with, apart from the size and age of the individual larva, there is very little initial indication that it is going to leave the foodplant and look for a pupation site. My larvae pupated 54 to 65 days after hatching from the egg. A fully grown larva is typically 20mm in length and lime green in colour.
It is still green when it stops feeding and descends to the ground, showing just a few brown flecks under the skin. Around 6 hours later it has achieved a transitional colour, halfway between green and brown. Once it is at this point, the brown colouration fully asserts itself within a period of just a few hours. Thereafter it rests in the leaf litter for a few days and does not feed again.
The final site for pupation is very carefully chosen. Typically the larva spins a flimsy pad of silk to which it attaches its tail or hindquarters. It positions itself head down against a vertical surface or upsidedown flat against a horizontal surface. I gave mine the choice of dry leaves on top of layers of dry and moist compost. Two larvae chose the leaves and the other preferred a cosy corner of the pupation pot.

Once attached to the silk pad the appearance of the larva changes into a more rounded shape as it contracts. It stays like this for around 4 days and becomes increasingly transparent as it approaches pupation. Unlike most butterfly larvae which enter this stage, the shape and colour of the pupa begins to become visible through the larval skin. At the point of pupation the larval skin becomes completly transparent and is slowly sloughed off, ending up as a compact mass attached to the rear of the pupa. The fresh pupa is pink, but it soon darkens to its final brown form.
Based upon a 40-day pupation period, the estimated emergance dates for the adults are 13th July, 21st July and 23rd July.
Watch out for my final report

Vince

Vince
This is amazing, and beautifully presented work.
I am enthralled, and can't wait for the next instalment.
Thanks

Fascinating stuff. They look so vulnerable just lying there on the ground.

dilettante wrote:Fascinating stuff. They look so vulnerable just lying there on the ground.

As indeed they are, presenting a succulent and nutritious delicacy for many insectivorous beasts from shrews to carabid beetles.

Brown hairstreaks are also notable among their kin for not showing the least tendency towards cannibalism. Black, purple and green hairstreaks show a decided fondness for devouring the prepupae of their brethren if given the opportunity to do so.

Excellent detailed observations Vince, enhanced by your superb photographs.

Piers.

Yes, a fantastic, illustrated account, Vince. I'm really looking forward to seeing the emergence.

Guy

Top notch, Vince

Agreed. One of the main reasons why this site is so good.

Agree wholeheartedly with all the other commentees, a fascinating insight, I'm learning so much from the efforts of members such as yourself Vince. Superb images to compliment the different stages, look forward to emergence days now.

Bill