Crown-of-thorns starfish

The crown-of-thorns starfish (Acanthaster planci) is a starfish with thorn-like spines sprouting all over its body for protection. These echinoderms grow to a diameter of up to 40 cm across and have 12 to 19 arms extending from their center. If accidentally touched or stepped on by humans, the starfish's long spines (which release a neurotoxin) are capable of pricking and stinging, inflicting great pain that can last for hours, as well as nausea and vomiting. Frequently, the area around the puncture turns a dark blue (erythema) and begins to swell (edema). The swelling may persist for a number of days or weeks. If you are pricked by a crown of thorns, it is important to ensure any remnants of the spine are completely removed.
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