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How do some tunicates protect embryos before larvae develop?

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Bright blue sea squirt Rhopalaea crassa with yellow-edged openings grows on a coral reef among various corals in the Philippines. — tunicate Blue spot sea squirt (*Clavelina moluccensis*), a colonial tunicate.

While primitive tunicates typically release their eggs into the surrounding water for fertilization and development, many species provide parental care to protect their offspring. In these cases, the embryos are retained within the female’s atrium or other internal structures until the larva is fully developed. This trend toward parental care is particularly evident in colonial forms of these chordate animals.12