Stylasterina

hydrozoan order

Also known as: Anthoathecata

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Last updated

July 14, 2026

Quick Summary

Stylasterina is an order of hydrocorals within the class Hydrozoa. These marine organisms are closely related to millepores and were once grouped with them in the order Hydrocorallina. Stylasterina colonies are typically erect and branching, though some are prostrate. They commonly display yellow, red, or purple coloration. Unlike millepores, their reduced medusae do not become free but develop and produce gametes within cavities in their skeleton, known as ampullae. These hydrocorals are found worldwide.12

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Annotated classification
Order Stylasterina Hydrocorals. Resembling millepores; colonies erect and branching or prostrate. Commonly yellow, red, or purple. Reduced medusae not freed; develop and produce gametes in cavities of skeleton (ampullae). Worldwide; includes precious red coral, Corallium. Order Trachylina Medusa dominant; reduced or
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Order Stylasterina Hydrocorals. Resembling millepores; colonies erect and branching or prostrate. Commonly yellow, red, or purple. Reduced medusae not freed; develop and produce gametes in cavities of skeleton (ampullae). Worldwide; includes precious red coral, Corallium. Order Trachylina Medusa dominant; reduced or
Read More