Just analyzed:

https://www.sciencenews.org/article/sea-anemone-venomous-stinger-launch-prey

"A new look at the starlet sea anemone’s stinger gets right to the point.

Live-animal images and 3-D computer reconstructions have revealed the complex architecture of the tiny creature’s needlelike weapons. Like a harpoon festooned with venomous barbs, the stinger rapidly transforms as it fires,

***

"In the wild, the starlet sea anemone (Nematostella vectensis) can live in salty lagoons or shallow estuaries, where freshwater rivers meet the sea. Its tubular body burrows into the mud, and a crown of Medusa-like tentacles reaches up into the water, waiting for dinner to drift by (SN: 5/7/13). Each tentacle is packing heat: hundreds of stingers that can mean death for brine shrimp or free-floating plankton.

"These stingers are among the fastest micromachines in nature. An anemone can jab a predator or nab some lunch in about a hundredth of a second, says Karabulut, also of the Stowers Institute. Scientists had an idea of how such stingers worked, but until now, had never gotten so up close and personal.

***

"Packed inside a stinger’s capsule, a venomous thread coils around a central shaft. When triggered, the shaft explodes out of the pressurized capsule and extends, turning itself inside out like a sock. Finally, the thread races up through the shaft, sending its barbs into an animal’s soft tissue.

"Each stinger is good for just one shot. “It’s a one-hit wonder,” Karabulut says. “Once Nematostella uses it, it’s gone.'”

Comment: Another example of an irreducibly complex organ, which is so complex it had to appear all at once in complete form. This shows a designer is required.