It is said that bifocals were dreamed up a couple of centuries ago by Benjamin Franklin But the larva of the sunburst diving beetle Thermonectus marmoratus, an attractive native of southern America and Mexico, might stake an earlier claim to the invention - it's the only animal known to have naturally bifocal vision.
With 12 eyes and a fearsome array of biting, slicing mouthparts that are able to tear prey to shreds, the sunburst's hunting prowess is only enhanced by its ocular abilities.
The magic happens in the beetle's four largest eyes - long, tubular, forward-facing structures that allow it to focus on its mosquito prey both when stalking it from afar and when close enough to strike.
What's more, behind each lens are two light-sensitive retinas, one positioned behind the other, which enable the sunburst to focus simultaneously on the foreground and background without having to adjust when flitting between them.
This is, arguably, nature's best-looking beetle - in more ways than one.
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Top image: © Mason S. – some rights reserved (CC BY-NC)
