Papilio caiguanabus (male)

[Trehopr1]

To add a little cuban "spice" to our subject matter
I offer a cuban endemic not often encountered in
most private collections. Females have the row of
yellow spots on the forewings but, have white bands
(in place of the yellow bands) which occur on the
hindwings of the males.

[Chuck]

The female I was offered, and declined, the HW spots were definitely powder blue. IIRC I'd posted a photo on the old site.

[Trehopr1]

It could be that you observed a reasonably fresh specimen of the species or the color varies somewhat on the female's hindwings.

The only female which I have ever personally seen in a collection was some years ago and if memory serves it had been collected sometime in the 1950s. Perhaps on such an old specimen it had lost some of its powdery blue coloration with age and time.

[eurytides]

If the blue is a structural colour (often the case), it should not fade with age alone, no?

[adamcotton]

The blue of the Graphium eurypylus group species fades quickly, where as that of G. sarpedon does not. Possibly P. caiguanabus also fades, which would suggest it is not structural.

Adam.