scyphistoma

invertebrate zoology

Also known as: scyphopolyp

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June 17, 2026

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The scyphistoma is a sessile polyp stage in the life cycle of certain jellyfish, belonging to the class Scyphozoa. This polyp form is produced sexually and asexually buds off young medusae, also known as ephyrae, which then develop into adult jellyfish. After a period of free-swimming, a planula larva attaches to a surface and grows into a new scyphistoma, completing the cycle. While true jellyfish are marine and belong to Scyphozoa, freshwater jellyfish, like those in the genus Craspedacusta, are in the class Hydrozoa and also have a polypoid stage that produces medusae. The scyphistoma stage is a crucial part of the life cycle for many scyphozoan jellyfish, enabling asexual reproduction and the development of the free-swimming medusa form.123

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binary fission
…organisms, such as tapeworms and scyphostome polyps, is called strobilation. Commonly, this results in a chain, called a strobilus, of the fission products—the proglottids of tapeworms and the ephyrae of scyphozoan jellyfish; each proglottid or ephyra matures in turn and separates from the end of the strobilus. A few metazoan…
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…organisms, such as tapeworms and scyphostome polyps, is called strobilation. Commonly, this results in a chain, called a strobilus, of the fission products—the proglottids of tapeworms and the ephyrae of scyphozoan jellyfish; each proglottid or ephyra matures in turn and separates from the end of the strobilus. A few metazoan…
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jellyfish
A sessile polyp (scyphistoma) stage asexually buds off young medusae from its upper end, with each such ephyra growing into an adult. The adults are either male or female, but in some species they change their sex as they age. In many species, normal fusion of egg and…
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A sessile polyp (scyphistoma) stage asexually buds off young medusae from its upper end, with each such ephyra growing into an adult. The adults are either male or female, but in some species they change their sex as they age. In many species, normal fusion of egg and…
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cnidarian
Reproduction and life cycles
In most scyphozoans, a scyphistoma (scyphopolyp) produces immature medusae (ephyrae) by asexual fission at its oral end. This process, called strobilation, results in eight-armed, free-swimming ephyrae.
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In most scyphozoans, a scyphistoma (scyphopolyp) produces immature medusae (ephyrae) by asexual fission at its oral end. This process, called strobilation, results in eight-armed, free-swimming ephyrae.
Read More