Craspedacusta sowerbyi

jellyfish

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Last updated

July 23, 2026

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Craspedacusta sowerbyi is a freshwater jellyfish, though not a true jellyfish as those are exclusively marine. It belongs to the class Hydrozoa and is found in the Northern Hemisphere.1

This organism has a bell-shaped body, about 2 cm (0.8 inches) in diameter, with numerous short tentacles around its edge. It exists in two forms: a small, sedentary polyp and a free-swimming medusa. The polyp, which lacks tentacles, asexually buds to produce the medusa. The medusa reproduces sexually, with male and female individuals producing gametes that unite to form a larva, which then develops into a polyp.1

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freshwater jellyfish
Craspedacusta sowerbyi, which is widespread in freshwaters of the Northern Hemisphere, grows to about 2 centimetres (0.8 inch) in diameter. Several hundred short tentacles extend, fringelike, from the margins of the animal’s bell-shaped body.
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Craspedacusta sowerbyi, which is widespread in freshwaters of the Northern Hemisphere, grows to about 2 centimetres (0.8 inch) in diameter. Several hundred short tentacles extend, fringelike, from the margins of the animal’s bell-shaped body.
Read More