Tucked away mostly unnoticed into the corner of your eye is small fold of membrane that serves practically no purpose whatsoever.

HEAD TO NO From your plica semilunaris to Darwin’s tubercle – the 10 ‘pointless’ body parts you never knew existed Including one that acted as a kneecap in Old World monkeys Alice Fuller ...

Now, the plica semilunaris (also known as the semilunar fold) and its associated muscles are useless, but there hasn’t been enough evolutionary pressure for the trait to disappear completely. By ...

This, along with the Plica semilunaris, which is that little membrane just next to it, are actually thought to be the vestigial leftovers from your "third eyelid". Lots of other animals on Earth ...

Plica semilunaris: What??? You don't have one of these, do you? Well, yes, you do. The Plica semilunaris is the red, fleshy-looking structure in the corner of your eye. This used to be a second ...

At the very corner of your eye, next to your nose, there’s a little flap of skin that doesn’t really need to be there. This is called the plica semilunaris, or the nictitating membrane.

The caruncle (from Latin caro=flesh) is a soft, pink, ovoid body, about 5 mm high and 3 mm broad, situated in the lacus lacrimalis medial to the plica semilunaris. 1 It is more prominent on ...

You’ll notice a small patch of pink called the plica semilunaris. This is the remnant of a nictitating membrane, which likely first protected your ancestors eyes as they were hunting down prey ...

Closer to home, the human appendix is a good example of a vestigial trait (although there’s now some evidence it may not be useless after all). But there is a weirder one, the plica semilunaris.