machaon complex 2

Klaas,

Brilliant! It seems that you have a similar hypothesis to me, and we are both examining this by breeding experiments. My Swedish machaon are laying eggs at the moment, and I will be very interested to see if they become multivoltine under hot climatic conditions, and whether their phenotype alters as a result of rearing them under non-native conditions.

I am also rearing machaon from Malta, Italy, Austria and Japan at the moment, and made crosses between Austrian machaon with hippocrates and Swedish machaon with hippocrates to test the Japanese theory that they are separate species. Currently the larvae of these 'hybrids' are starting to pupate. I have also made a cross between machaon brevicauda male from Quebec and Austrian machaon female, which laid on carrot and these are starting to pupate too. Interestingly the opposite cross, using brevicauda female was a total failure because the brevicauda female refused to lay eggs on fennel, carrot, celery and some other Apiaceae or even Ruta. I think I must try to obtain seeds of the local hostplant and grow those before trying again next year. Of course the next stage with all the hybrid crosses is to check the sex ratio of the hybrids and test their fertility at the next generation to see if they really are the same species as DNA studies suggest.

Of the names you mention above, only emisphyrus and hispanicus are available names, the other 3 (tertiana, gigantea, and pseudobigeneratus) are all infrasubspecific like lapponica. I am strongly inclined to agree with you that all of the European mainland machaon (including the eastern Mediterranean too) belong to the same subspecies, with britannicus and melitensis as distinct local subspecies. I am not certain yet whether gorganus should be retained as the name for this subspecies, or the whole of European machaon be regarded as ssp. machaon. Hopefully the results of my breeding experiments will help clarify this, but my instinct is that they are all the same population in reality, at least they were in the very recent past (unfortunately European butterfly populations have declined so much over the past 100 years of industrialisation that there are often only scattered isolated populations where they used to be much more widespread).

Adam.

Perhaps the larvae didn't get enough daylight in your room. The trigger to initiate diapause is for 5th instar larvae to receive daylength of less than 10 hours per day. It seems that the daylength for smaller larvae is not critical, only the 5th instar.

In fact I will have to use this method to artificially induce diapause in May, as machaon cannot survive the rainy season here from May to October, as it is too wet and humid. I will put them in an airconditioned room with lighting for only 8 hours per day which should trigger diapause, then put the pupae in the fridge until late October when I will bring them out to continue my breeding experiments. Our winter temperatures in December-January are about 20-25C with bright sunshine most days, so they should breed well then. Right now its 30C+ every day, and the Swedish machaon don't seem to mind that at all. Hopefully they won't mind the 40C temperature in April!

Perhaps you can answer one interesting question, in natural conditions in Scandinavia how long does the larval stage (from hatching to pupation) last? The adults of Swedish machaon are very large, and I suspect this is a result of relatively lower temperatures at the larval stage, so they grow slowly and eat more as a result. The current generation of hippocrates are pupating now, and the larval stage only lasted about 2-3 weeks. The pupae are the same size as the overwintering pupae, so it will be interesting to see if they produce spring form adults (very easy to tell the difference in hippocrates, as the hw anal eyespot is different between spring and summer forms) and the next generation becomes summer form, or perhaps they will produce small summer form specimens. I suspect that there may well be 2 spring generations in warmer parts of Japan too.

Adam.

and a Finnish machaon in our garden, late June 2010

Main flightperiod is also June, through July here in Norway...
There has been records of machaon as late as beginning of September here. And as early as first half of May.

In Sweden the partial second generation is almost yearly in the southwest part regardless of weather. Seems less frequent in other parts.
I breed outside to get the most natural condition I can provide and keeping the pupae in the same cage got the result that some of them went to second generation and some not. Next year I will keep track of how many and put them in different places (more or less sun and more or less rain) to see if there's any difference.

In Sweden the first generation larvae is 3-5 weeks. The second generation is a week longer with the last larvae still being on the plants during the first frost nights.

I started to assemble all information I could track down for papilio machaon - all that is relevant for the Swedish envirnoment as my scope is only to provide local information. My website is not finished and if anyone can help me get more or more accurate information I'd be grateful. Send me a personal message on this site.
www.mindserver.se/makaonfjaril.html
It's in swedish but use any translator, or use the button in the upper right corner to get google translation to english..

I had a look at your website and my Swiss pupae are very similar to your Swedish pupae. My Swedish pupae are paler in ground colour, the dark ones are almost white with black markings. So these differences may be caused by different breeding conditions only.