On the 17th of December, I collected the wings of a Danaus genutia (the common tiger ) butterfly in order to continue my comparative study of the scales of various species belonging to the order Lepidoptera.
Lepidopterans (which loosely translates to ‘scaly wings’) have scales present on the wings that play a role in thermoregulation . These scales may or may not be pigmented and diffract light to produce the different patterns that we see on the wings of butterflies and moths. Another surprising advantage that these scales provide is the ability to escape from spider webs as the scales detach easily making the wings slippery and thus, allowing for an easy escape.
Danaus genutia (the common tiger ) butterfly is quite commonly found across India. I obtained this specimen on a recent trip to Kanakapura, Bangalore. I took the “dust” from its wings and observed it under the foldscope and was a little surprised with what I saw.
I have previously observed the scales of two moths – I have posted about this in a previous article- and what I observed was quite different ( https://microcosmos.foldscope.com/?p=96224 ). Below are pictures of the scales from two moth species.
Below is a picture of the scales from the butterfly.
The difference between the scales of the wings of a moth and that of butterfly is quite clear. The scales on the moth appears to have sharper edges while that of the butterfly is smaller and more rounded off. I hypothesize that it is this fact that makes the dust of moth wings and thus, the moth itself a more potent allergen as compared to butterflies.