sea wasp

marine invertebrate

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July 13, 2026

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The sea wasp, scientifically known as Chironex fleckeri, is an extremely venomous box jellyfish found in Australia. It possesses a bell that can grow over 11 inches (28 cm) wide, with tentacles extending more than 78 inches (2 meters). This marine invertebrate is among the most venomous of all jellyfish, capable of causing death within minutes. The sea wasp's venom, specifically cardiotoxin, can lead to immediate and excruciating pain, seared lines on the skin, circulatory failure, and respiratory distress, often resulting in rapid death.12

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10 Deadly Animals that Fit in a Breadbox
Sea Wasp
The sea wasp is a type of jellyfish found in the Indo-Pacific region. It would probably have to fold up its tentacles to fit in your breadbox, but its bell grows only to about 10–12 inches (25–30 cm) in diameter. A sea wasp’s…
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The sea wasp is a type of jellyfish found in the Indo-Pacific region. It would probably have to fold up its tentacles to fit in your breadbox, but its bell grows only to about 10–12 inches (25–30 cm) in diameter. A sea wasp’s…
Read More

cnidarian
Size range and diversity of structure
…Asia, and include the so-called sea wasps. The polyp is tiny and inconspicuous.
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…Asia, and include the so-called sea wasps. The polyp is tiny and inconspicuous.
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jellyfish
and Chiropsalmus, commonly called sea wasps, occur widely from Queensland northward to about Malaya. These forms have remarkably sophisticated eyes, and they are dangerously venomous; a moderate sting can cause death within a few minutes. In all the box jellies so far studied, the polyp stage produces but a…
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and Chiropsalmus, commonly called sea wasps, occur widely from Queensland northward to about Malaya. These forms have remarkably sophisticated eyes, and they are dangerously venomous; a moderate sting can cause death within a few minutes. In all the box jellies so far studied, the polyp stage produces but a…
Read More