amphiblastula

sponge

Written by

The Information Architects of Encyclopaedia Britannica

Last updated

June 18, 2026

Quick Summary

The term "amphiblastula" refers to a specific type of free-swimming larva found in certain sponges. This larva is characterized by having small, flagellated cells in one half and larger, non-flagellated cells in the other half.1

During sexual reproduction in sponges, fertilization occurs, leading to the development of an embryo. This development can result in different types of larvae, including the amphiblastula. The amphiblastula larva is oval-shaped and possesses a central cavity. Its front half is composed of cylindrical, flagellated cells, while the rear half consists of round cells lacking flagella. The larva uses its flagellated portion to swim. After a period of swimming, the larva attaches to a surface and metamorphoses into a young sponge.2

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

2 Britannica Sources

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.

sponge
Sexual reproduction
, Oscarella), called an amphiblastula, is oval in shape and has a cavity in the middle; the front half of the larva consists of cylindrical, flagellated cells, the other half of round cells without flagella. The larva swims with the flagellated portion forward. The amphiblastula is preceded by a…
Read More
, Oscarella), called an amphiblastula, is oval in shape and has a cavity in the middle; the front half of the larva consists of cylindrical, flagellated cells, the other half of round cells without flagella. The larva swims with the flagellated portion forward. The amphiblastula is preceded by a…
Read More