Salticids have fantastic vision and some of the "sharpest" eyes of all arthropods. The larger anterior median eyes you see here are of a higher acuity, and are additionally of a higher focal length - effectively like little telephoto lenses! Meanwhile, the anterior lateral eyes (and the remaining sets of latero-dorsal and posterior eyes) have a wider focal length - a bit more like blurry fish-eye lenses. Salticids look around not only by moving their cephalothorax, but also by shifting around their internal retina with small muscles connected within their cephalothorax. Next time you spot a salticid, get down in his/her face and check if you can see washes of color move about within their eyes. When their eyes are at their darkest - he/she is looking right at you!
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