The world is full of cool beetles. I mean, REALLY full of these hard-shelled little - and sometimes big - charmers. The order Coleoptera is huge; it contains some 400,000 described species and experts think that that many again, if not more, have yet to be described. In many habitats, beetles are the most numerous type of animal. A great many are tiny and nondescript, apt to be passed by without ever being seen.
Not these two.
Up close and personal with the business end of a pleasing fungus beetle at the chow line. This animal displays classic aposematic - warning - coloration. The carapace is boldly ornamented in brilliant orange, forming a striking and very obvious contrast with the gloss black base coloration. The jarringly conspicuous coloration pattern, coupled with its diurnal - daytime - habits and fearlessness, strongly suggest that this is a beetle that you do not wish to eat. As many species of fungus are toxic, I assume that these beetles are too.
The pleasing fungus beetles were certainly cool, but they may be trumped by these golden tortoise beetles, Charidotella sexpunctata. They aren't big - it'd take a few dozen to make one of the aforementioned pleasing fungus beetles - but they sure are neat. In this photo, a pair works diligently to ensure that more tortoise beetles grace our landscapes. This species noshes on plants in the morning-glory family, and if you've got morning-glories in your garden, you may have your life enriched by these wee beetles.
In 1979, entomologist Edward Barrows published a wonderful paper on this species, and another similar tortoise beetle. You see, tortoise beetles are chameleonlike and can change color, which adds greatly to their allure. Barrows documented that a tortoise beetle can shift its colors in as little as 12 seconds. When all is well and they're having fun, such as in this photo, a bronzy-gold metallic cast is normal. As light plays over the beetle, glancing off its shell at different angles, a rainbow of blues, greens, and even purplish tints are reflected back.
In the course of making these photos, I felt it necessary to horn in and reposition the beetles for better photo ops. They didn't like it, and when I disturbed the pair, this male went from the rainbow display of the former photo to this dull blood-red coloration in seconds. Apparently these color shifts are accomplished by forcing fluids into tiny cells, or chambers, in the carapace which in turn changes the way that light refracts off the shell. How cool is that?
Beetles may be small, but they certainly can be sublime.