Monday, 19 May 2014

Update on the Green-veined White butterfly

In the previous post I showed a photograph of a Green-veined White butterfly and wondered if it was a gynandromorph. This is the image:

Gynandromorph Green-veined White butterfly
My first thought was that the butterfly was entirely female, but the right wing had been rubbed or damaged in some way, removing some of the scales and hence the pattern. But then I realised that the pattern on the right wing looked exactly like the pattern on some male wings. I then noticed that the abdomen is 'kinked' rather than straight, which is a feature that I have seen in other gynandromorph images, though admittedly of different species. I suppose that if the internal organs are male on one side and female on the other, then the inconsistent internal structure will be reflected in some way in the outer surface.

I showed the image to a number of people and it has now been confirmed as a very rare bilateral gynandromorph.

Bilateral gynandromorphs are female in one half and male in the other, and arise from incorrect cell division at some very early stage in the development. They are very rare and I have been unable to find any other images of this particular gynandromorph anywhere in the literature or on the internet.


Gill said...

Fascinating, and well spotted. I wonder if they are able to mate and pass on the condition (I guess it is "epigenetic", essentially a faulty switch in development).

I wonder what other GVW make if this? Is it always female on the left, male on the right.

amanda peters said...

Find this very interesting , although many will be missed as we don't always see what we are looking at.

stuart dunlop said...

@Gill:Apparently they can't mate, but these are so rare that they haven't been studied to any depth. Other GVW were ignoring it (maybe they were getting mixed signals from the wings), Orange Tip males were having a look, but they examine bits of white paper, so that's no surprise. The very few other gynandromorph images that I have seen can be male or female on either side. There is another form of gynandromorph ('checkerboard') where slivers or other portions of wings (and presumably internals) can be opposite-sexed. I have no idea how those can come about. As far as I can tell, this is the first gynandromorph GVW record that has been published anywhere.

@Amanda: I doubt that a serious butterfly enthusiast would miss this: it certainly drew my attention. The chap who maintains butterfly UK says he hasn't seen one in 40 years of looking.