Allancastria cerisyi Male Ecloses

The first of our eastern festoon (Allancastria cerisyi) pupae has eclosed.

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Now that we are in Ithaca, it is unlikely that we will be able to find a convenient source of pipevine (Aristolochia) in a timely manner, but it is still an experience just to see these eastern festoons (Allancastria cerisyi) as they emerge. The first of 12 pupae eclosed today. This one, unsurprisingly, is a male.

Although we were there when it first crawled out of the pupal shell, the expanding of the wings was unexpectedly fast (~5 minutes), perhaps because it is so small, so only the final stages were captured in photograph.
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This is the first representative of the Parnassiinae subfamily that we ​have seen in real life. While many of the features are unmistakably swallowtail (Papilioninae)-like, such as the general wing shape, venation, and spot placement; and the shape of the body, antennae, and eyes. However, we cannot help but notice that it also shares some semblance to the pierids (Pieridae), Papilionidae's closest relative, in wing and body shape. 

The male's clasper is not quite conspicuous as a swallowtail's because the two closing flaps are not very large. The hooks and other machinery are there when it is squeezed open, but this made it hard for us to sex it initially. It seems, though, that the males such as this one lack a lot of the black spots of the female which have an overall much darker look. 

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Brian Liang
Brian Liang is a student at Cornell University in Ithaca, New York pursuing an undergraduate degree in entomology. He is co-owner and a main contributor to the Liang Insects blog, insects articles, and site design.

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