Laothoe populi problem

  • Hello!

    I have bred this species many times, but I haven't encountered such a problem before.

    For some reason the moths couldn't get out of the pupae on their own. And when I took them out of the pupae myself, they could no longer spread their wings, some were already dead. Only a few individuals hatched successfully. Very strange...

    What happened to them?

    Smerinthus ocellatus pupae were kept in the same conditions and all hatched successfully.

  • AD
  • Hi,

    I sometimes have this phenomenon in breedings, where at the end, shortly before pupation there are infections and diarrhea in the caterpillars. In most cases, more or less caterpillars manage to perform the pupation skinning.

    However, it is often the case that the hatch of these imagos, or at the latest the mating behavior of the imagos, causes problems.

    Maybe this is also true in this case?



    ich habe dieses Phänomen manchmal bei Zuchten, bei denen zu Ende hin, kurz vor der Verpuppung es zu Infektionen und Durchfall bei den Raupen kommt. Meistens schaffen es dann noch mehr oder weniger viele Raupen die Puppenhäutung zu vollziehen.

    Allerdings ist es dann oft so, dass der Schlupf der Imagos, oder spätestens das Paarungsverhalten der Imagos Probleme bereitet.

    Vielleicht trifft dies ja auch in diesem Fall zu?

  • Hi, Rudi. Thank you for your reply.

    What you described I have already experienced breeding Marumba quercus. There was a female who became infected just before pupation, she had diarrhea. Nevertheless, she pupated and then hatched with incorrect wings.

    In the case of Laothoe populi, everything is completely different. There was definitely no diarrhea, the caterpillars were large and healthy looking. This is very strange, because the caterpillars of Smerinthus ocellatus were raised on the same poplar and went through the process from caterpillar to imago without any problems.

    I thought maybe the problem was that I kept them in the refrigerator for too long and then suddenly took them out in thirty-degree heat? 🤔


    An important update! I opened the remaining pupae, they are all empty with brown and green liquid inside. It turns out that you were right, is it an infection? is this a virus or what is it? Or maybe the sawdust in which I throw them for pupation is infected?

  • Hi,

    First of all: I think you may exclude any problems raised by potentially infected sawdust - It is not conceivable that sawdust bears some nasty germs. I use sawdust since many years as a pupation/storage medium, and never came across with any detrimental experience.

    On the other hand, it is difficult to trace down the reasons for the observation you reported. The `temperature shock` you mentioned may have impaired the pupae; however, it seems to me that a specific infection may have caused the problems. The brown liquid within the pupae (in most of them???) strongly indicates in this direction; especially, if these pupae disseminate an awful smell, it is pretty sure that any bacteria are the reason.


  • Hi, Lepidopterix

    I agree with you. I also use sawdust for over nine years for pupation and storage, without any problems. Yes, it turns out that more than half of the pupae were with this brown liquid. Yes, there was a smell. I've encountered infected individuals among wild ones before, but not among home-grown ones and in such quantities. Some serious infection.

    Thank you very much for your reply 👍🏻

Participate now!

Don’t have an account yet? Register yourself now and be a part of our community!