The Butterfly Scale Competition

"THE BUTTERFLY WING SCALE COMPETITION"

In the two most recent issues of Insectifera, we announced a competition asking which tropical butterfly was depicted and what colour the scale had, and "why"?

Was the competition too difficult for Insectifera's readers?

Since the answer is interesting from many "perspectives", the competition was not announced in the last issue. A few clues were presented:

A large butterfly, 12–15 cm between wing tips
A rainforest species, fairly common

Red and white banded colonial larvae

A dream for many to see this animal fly in the sun
Wing scale structure very interesting

See photo from scanning electron microscope in our previous issue in very high magnification and the image below of the same wing scale in somewhat lower magnification.

Morpho catenarius > Wing
"at appropriate magnification"

Distribution: Southern Brazil, Paraguay, Northern Argentina

The answer has a connection to Jan Isidorsson's article on Iridescence. Jan's article is also in some ways a result of this competition. Jan therefore cannot participate in the competition. Unfortunately, we have not received any completely correct answer.

However, Krister Frid guessed at some Argentinian Morpho butterfly.

This is the closest answer we received and Krister thus becomes the winner of the competition. Congratulations Krister!

Prize presentation at this year's autumn meeting!!

The correct answer was Morpho catenarius. In Swedish, this beautiful butterfly can appropriately be called the Marbled Heaven-wing. The Swedish name refers to its underside. Particularly the female is very beautiful and distinctly "marbled". As is evident from the scanning electron microscope image in our previous issue, the wing scale is heavily perforated, in contrast to the wing scales of the blue Morpho butterflies, which are all extremely smooth and whole.

I assume, albeit without evidence, that it is this "perforation" that makes the wing colour very pale. The perforated surface means that the wing scale's surface contains much air. Morpho catenarius is one of the palest of all Morpho species. It is also not as glossy as those species that have the wing scale surface covered with a smooth "wave-like structure".

New BUTTERFLY COMPETITION!

What is the butterfly called? A simple question, yes, but a simple answer?

Look carefully at this butterfly and especially its wing shape, the structure of the wing veins, the antennae. It is certainly quite remarkable. Otto Staudinger had this creature in his hand during the 1870s. Judging from the name he gave the butterfly, he must have thought this was something utterly remarkable from another world, and he was right about that. The Latin name he came up with is probably one of the most remarkable ever given in the Linnaeus system.

The butterfly is shown at double size so that you readers can more easily study the animal. The colours are reminiscent of those of a hawthorn butterfly female, although the wings are probably more transparent. The depicted specimen is a female. The male is somewhat smaller and somewhat darker.

If you cannot figure out the species or genus name, perhaps you can guess which family this unique butterfly was placed in.

A tip: The butterfly is found in one of D'Abrera's books on page 107