Small white pupae

[Padfield]

Last year, I watched a female green-veined white laying on wild rocket and collected some of the eggs on several plants. There was also a female small white in the patch, and when the caterpillars were mature enough to identify, I was told they were all small whites. Very strange - I even photographed the green-veined white while she went about her business. ANYWAY, they all pupated within days of each other and began emerging this spring. The first (a female) appeared on 18th April, the second (a male) on 25th April and the third (another female) today, 5th May. Here she is:





And here is her pupal shell, with meconium stains on the mesh:



During the recent storms, I moved the cage to shelter but even so one pupa got detached from where it had fixed itself on the clear plastic front of the cage. I searched for it and found it on the soil in one of the plant pots (the same pots the caterpillars lived in, which I now use for weighing down the cage):





Can one of the experts tell me if it is OK to leave the pupa like this, unattached but relatively sheltered and safe? Will the butterfly be able to emerge normally?

Guy

[Vince Massimo]

Hi Guy,

I would be inclined to move the pupa off the ground and away from predators that are found there. An aerated pot with some sticks in it would be best. It can stay in the cage, but shaded from direct sunlight.

Vince

[Padfield]

Thanks Vince. I'll move it somewhere safer tomorrow morning - no horrible weather forecast before then and there are no obvious predators in the cage. I was wondering if the pupa needed to be affixed to anything for the butterfly to get out normally, but I take it the answer to that is no.

There's just one pupa with different colouring that might just be a green-veined white ... That one is now dangling by a single thread (amazing how strong the threads are) so I might cut it down and put it in a safe place too.

Guy

[Vince Massimo]

Hi Guy, when the butterfly emerges from its pupa it will naturally crawl to the nearest non-horizontal surface in order to suspend itself for wing expansion. Just make sure that there are sticks nearby and the bottom of the pot has holes in it to avoid rainwater build-up.

Vince

[Padfield]

Thanks again, Vince. Your input is always really helpful. I'm a complete beginner with captive-rearing.

The eggs were laid on 26th August 2020 and began hatching on 4th September. The caterpillars pupated at the beginning of October and have been outside, in a mesh cage, ever since, through storm and wind, snow and rain. I kept the cage in the shade of trees until I saw my first small white flying in the garden, then moved it into the open, oriented the same way as when the caterpillars pupated, so they would have the aspect they initially chose.

Guy

[Benjamin]

Very interesting Guy. It’s inevitable that most of us gravitate towards the headline species, but ‘cabbage whites’ really are fascinating! For a couple of years a while back I lived in a first floor flat in London and had only a window ledge to play with. I grew various Brassicaceae and had a wonderful time with the the large and small whites that bred on them. The arrival of the first butterflies to our plants really was a joy.

As for your fallen pupa - as Vince says it’ll prob emerge absolutely fine, but gluing (or otherwise attaching) the cremaster to something would help the butterfly push/pull itself out from the pupal shell. We used to glue hundreds of pupae every week at the butterfly house in this way and it resulted in a much better success rate than if ever they were left loose. Pierids and Papilionids should be glued and tied along the length of a stick head at the top, and not hang from it, as they ‘expect’ to be able to grip something and walk free from the pupal shell as soon as their legs are free. Occasionally butterflies that attempt to emerge from unattached pupae fail to completely shed the pupal shell and as a result cannot expand their wings properly. Obviously recreating as natural a position as possible is the goal, and this clearly depends on the species.

As an aside I’m sure you are familiar with the lines of pupae you see in the emerging cage in butterfly houses, as I remember reading that you used to visit Papiliorama regularly. I was working at Stratford at the time and we used to send them their pupae (Stratford are the main importer). I only starting reading your diary some time later, but had I seen it at the time I could have sent you the Papiliorama packing sheet to help with IDs (though I do believe you were pretty much always right anyway)!

[Padfield]

Thank you, Benjamin. Fascinating to know you were a Papiliorama supplier! I don't know if you ever visited the place, but I can say your pupae went to a good home. It's not huge but it's big enough for the butterflies to fly free and behave more or less normally. I used to go on grim days, most often in the winter months. The site is in rather uninspiring countryside near Bern and it is always strange to walk in out of the cold and suddenly find yourself in a tropical paradise. I've posted a couple of videos of the inside on youtube:

https://www.youtube.com/watch?v=z2JDFr1nYyg&ab[/video]
(https://www.youtube.com/watch?v=z2JDFr1nYyg&ab)

https://www.youtube.com/watch?v=945Aw8YGFhs&ab[/video]
(https://www.youtube.com/watch?v=945Aw8YGFhs&ab)

Back to business: I have some rubber-infused Loctite Super Glue. Will a couple of tiny blobs of this be good to secure the pupa(e)? I imagine they contain volatile solvents - I wouldn't want these to do any damage. Is the cremaster basically just a stalk? If so, I guess I can't do any harm.

Guy

[Benjamin]

We used to use copydex as I believe it is solvent free, but anything similar will do. But I’m sure you’re right that you won’t cause any damage to the butterfly via the cremaster anyway...
Once the cremaster is glued we would then use cotton to gently tie the pupa to the dowel and stand it upright as described earlier, or at least that was the idea, in reality more often than not they would just be left to hang as Nymphalid pupae but in such a way that the legs could reach the dowel when they are freed from the case (much more practical when you have hundreds of pupae to hang that look close to eclosion!).

I haven’t been to Papiliorama but it looks really good - quite similar to Stratford but with a bit more height. They are quite strange places - very often Stratford was full of school groups and throughout the day was generally chaotic. But we had some fantastic species and at times it was a privilege to work in such a place. I particularly remember the crepuscular flight of the various Caligo species that are an ever present in butterfly houses. Doing the final sweep of the flight area once the visitors had gone and in fading light, large trains of Caligos would bob after each other low to the ground around the winding paths - that I enjoyed!

Anyway - good luck with pupa!

[Padfield]

Thanks again, Benjamin.

As time is of the essence, I put a small blob of the Super Glue on a stick, put the cremaster into it and then very, very gently put a little cotton thread around. I did this for both the free pupae - which I think are both small whites now - and stuck the sticks into the weighting pots. The result:

Pupa 1





Pupa 2





I didn't attempt to knot the thread (I didn't want to pull it tight!) but just used sellotape to attach the free ends to the stick.

Now we wait ...

Guy

PS - I never had the opportunity to witness the nocturnal flights of the Caligo!

[Padfield]

The first of the two tied pupae has now emerged. This is the one that had pupated on the clear plastic side of the cage and been detached by the storms. I found him this morning, sitting on his stick:



His wings were still soft and it was cool, so I left him an hour while I taught, then returned to find him atop the stick:



I took him very gently outside and showed him his new home:



Then I placed him on a comfrey flower so he could fly off when he was ready:



The other pupa looks ready to open:



Meanwhile, another had emerged in the top of the cage. When I found him or her (I don't know yet) his/her wings were still a little crumply so I left him/her. What looks like a broken antenna is a leg - there are two perfect antennae:



So that's five adults so far from 7 overwintered pupae.

Guy

[Padfield]

Later in the morning, the second pupa-on-a-stick emerged, and this time I was there!















It's a boy!

Guy

[Benjamin]

Great result and a lovely series of images.