brachiolaria

zoology

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Last updated

June 22, 2026

Quick Summary

A brachiolaria is a transitional larval stage in the development of certain starfishes. It develops from a bipinnaria larva and is characterized by three anterior processes that are homologous to those of the adult starfish. These processes are used by the larva to attach to the seafloor before it metamorphoses into a juvenile starfish.1

Starfishes, like other echinoderms, typically reproduce sexually. After fertilization, the egg develops into a free-swimming larva that feeds on plankton before transforming into a juvenile. This process is known as indirect development.2

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echinoderm
Development
…of development is called a brachiolaria, which has three additional arms used for attaching the larva to the seafloor. Echinoids and ophiuroids have complex advanced larvae closely similar in type. The larva, named pluteus, resembles an artist’s easel turned upside down. It has fragile arms formed by lobes of ciliated…
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…of development is called a brachiolaria, which has three additional arms used for attaching the larva to the seafloor. Echinoids and ophiuroids have complex advanced larvae closely similar in type. The larva, named pluteus, resembles an artist’s easel turned upside down. It has fragile arms formed by lobes of ciliated…
Read More