How do nematocyst toxins affect prey?

Nematocysts are specialized capsules found in cnidarians that serve as a primary mechanism for capturing prey and defending against predators. When a cnidarian makes contact with a prey item, the capsule triggers the eversion of a hollow, often barbed, tubule.12

The toxins contained within the capsule are injected through this tubule directly into the tissues of the prey. The primary effect of these toxins is the paralysis of the victim's tissues, which immobilizes the prey and facilitates its capture. In some species, the tubule itself may also be adhesive or capable of entangling the prey to assist in holding it. Once the prey is incapacitated, the cnidarian can proceed to consume it.123

While the specific microbiological mechanisms of these toxins can vary, they are highly effective at subduing various organisms, including fishes, worms, and crustaceans.3