What is this close-up picture? (WotsThat: Jellyfish tentacle)

Question

What object is shown in this zoomed-in close-up photo?

TurquoiseFault · Accepted Answer

Jellyfish tentacle. Jellyfish tentacles are covered in specialized stinging cells called nematocysts that fire in less than a microsecond, making them some of the fastest predatory structures in the animal kingdom. These tentacles can deliver venom even long after the jellyfish has died, which is why beached jellyfish should never be touched.

Answer: Jellyfish tentacle

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