When I ask people to name shiny, colorful insects, butterflies and the “regular” beetles (the common ones that people usually see, like ladybugs) are the ones that come up. There are many insects that people think as dull or drab, like wasps and the “ugly” beetles, like weevils. Since the most common scarabaeids here are brown or black, they too get thrown in the “ugly insects” pile. Yet nothing is further from the truth; earlier today, Bug Girl showed us some mind blowing cuckoo wasps, and I’d like to show you a few samples of the colorful beetles I’ve seen in the past few weeks.
When I showed this image to people, they thought it was some mineral deposit or a type of crystal in a rock formation.
But no, it’s not a rock! It’s a closeup of the elytra of a broad-nosed weevil (Curculionidae: Entiminae)
These colors are physical in nature; since they depend on the shape of tiny scales instead of chemicals, they don’t change when preserved in alcohol. The principle is similar to the one that the scales on a butterfly’s wing have, except butterfly scales vary greatly regarding shapes, and they tend to overlap; the scales in weevils tend to be rounded and either don’t overlap or do it in a disorderly fashion.
Myriad other beetle groups have very colorful members. One subfamily of scarabaeids, Cetoniinae, has some specimens that have elytra with a velvety surface. One fascinating aspect of these wings is that the colors vary with the ambient humidity; the higher the humidity, the darker the color of the beetle (This is very evident in another scarabaeid, the Hercules beetle). When wet, you can barely make out a pattern in the darkened forewings, but when they dry out a Rorschach-like pattern appears.
Yes, but this is all on the body/wings, you say. Bug faces are ugly, all black and boring. Again, the answer is no. Beetles have a vast array of colors, and in many cases this includes every part of the exoskeleton, including the head. Long-horned and tiger beetles have colors and patterns that rival those found in the masks of the Dancing Devils of Yare:
In short: beetles are awesome and they have some of the most amazing colors and textures in the insect world. I’ll do my best to keep showing you more examples of this!