Papilio memnon mating with bianor!

[Adam Cotton]

Today I was in a flight cage at my farm when I noticed a "butterfly commotion" in the cage backing onto the one I was in. When I looked round I saw a female Papilio memnon fluttering with a male hanging on in copulo below. I ran round to the cage and managed to get some photos of the event:






That would not be out of the ordinary, except that the male that was mating with the Papilio memnon female is Papilio bianor, as can clearly be seen in this photo:





I am not sure how long they had been mating, as they separated soon after I took the photos. It is likely that the female was not successfully fertilised, and the fluttering I saw may well have been the female trying to shake the male off her. Of course I immediately caught the Papilio memnon female and placed her in a separate flight cage which has no other butterflies in it, and will let you know if she does lay fertile eggs, and what results. She may well have been mated with a male memnon already, but she had only been released in the cage the day before.

Even if mating was successful it is rather unlikely that hybrid larvae will survive to adulthood, but at least the mating was the 'right way round'. A mating between male Papilio memnon and female Papilio bianor would produce embryos that would die before hatching from the smaller egg of Papilio bianor, as the head capsule would be too big for the egg that it was developing inside. As the egg of Papilio memnon is much larger that will theoretically not be a problem with this cross.

Adam.

[saye]

Is there any other record of this? Was your 'right way round' simply referring to the needed coupling of respective male-female species? I'm just clearing up if you've seen this the 'other way around'.

An hybrid is always such an exciting thing. Do tell us what follows.

[Adam Cotton]

No, I have never seen these two species mate before despite always keeping them in the same cage. Of course it could have happened when I wasn't looking, but there have never been any hybrids produced either. Papilio memnon and bianor are found together in nature and I have never heard of natural hybrids between them, so I rather doubt that this mating will produce offspring.

My reference to the 'right way round' was for any potential to get viable larvae. You can imagine that a larva that develops in a large egg has a large head capsule as programmed by its DNA, and a larva that develops in a small egg will have a small head capsule. A hybrid larva should have an intermediate sized head capsule, but if the cross is between the female of the species with small eggs and the male of the species with large eggs the embryonic larva will attempt to grow too big for the egg that it is developing inside, and thus will die as a result. Hybrid larvae can only develop and hatch from the egg if the mother is the species with the larger eggs.

I do have a series of hybrids that I was given back in 1980. A male Papilio polytes (small eggs) in a butterfly house in the UK mated with a female Papilio aegeus (large eggs) and they reared the offspring to adults successfully. Interestingly there are roughly equal numbers of both male and female hybrids, which are intermediate between the two parent species. Presumably the male Papilio polytes thought he was mating with a large female of the same species, as these two species don't naturally occur together. These are much more closely related to each other than Papilio memnon and bianor are, so there is a much higher probability of successful production of offspring.

Adam.

[jaguarae]

Cool !
May be some eggs .... and some hybrids
Let us know

[saye]

Jan 24, 2015 0:56:15 GMT -8 Adam Cotton said:

No, I have never seen these two species mate before despite always keeping them in the same cage. Of course it could have happened when I wasn't looking, but there have never been any hybrids produced either. Papilio memnon and bianor are found together in nature and I have never heard of natural hybrids between them, so I rather doubt that this mating will produce offspring.

My reference to the 'right way round' was for any potential to get viable larvae. You can imagine that a larva that develops in a large egg has a large head capsule as programmed by its DNA, and a larva that develops in a small egg will have a small head capsule. A hybrid larva should have an intermediate sized head capsule, but if the cross is between the female of the species with small eggs and the male of the species with large eggs the embryonic larva will attempt to grow too big for the egg that it is developing inside, and thus will die as a result. Hybrid larvae can only develop and hatch from the egg if the mother is the species with the larger eggs.

I do have a series of hybrids that I was given back in 1980. A male Papilio polytes (small eggs) in a butterfly house in the UK mated with a female Papilio aegeus (large eggs) and they reared the offspring to adults successfully. Interestingly there are roughly equal numbers of both male and female hybrids, which are intermediate between the two parent species. Presumably the male Papilio polytes thought he was mating with a large female of the same species, as these two species don't naturally occur together. These are much more closely related to each other than Papilio memnon and bianor are, so there is a much higher probability of successful production of offspring.

Adam.

I see. I understood initially the problem of head size/egg size and was only curious to know if any mating had happened in reverse. As for the mentioned hybrid, do you have any photos?

Thanks.

[Adam Cotton]

Here's a snapshot of a pair I took for you just now.

I don't know where the parents came from exactly (I was never told anything other than the species), but the male was probably polytes romulus from SE Asia and the female was likely aegeus from Australia at a guess.

Adam.

[saye]

Thanks, that was nice of you. I would have imagined them specimens of some noticeable variation, but they do look "intermediate" as you said.

[Adam Cotton]

Surprisingly they are not very variable at all. A couple of the males have less white at the subapical band of the forewing but most of them look just like the pair I photographed.

Adam.

[Adam Cotton]

The female Papilio memnon started laying eggs 2 days ago, and I can confirm today that at least some of the eggs laid on the first day ARE fertile. However, there is a distinct possibility that the female had already mated with a male Papilio memnon before the bianor male intervened. The eggs should start hatching in another 4 days, and maybe I will be able to tell if they are hybrid larvae or not then.

Adam.

[crazypapilio]

give it something new?

[Adam Cotton]

As I suspected, all the larvae were pure Papilio memnon.

Sorry, I forgot to post a follow-up on this one.

Adam.