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Which features do tunicate larvae share with other chordates?

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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.

Tunicate larvae possess several key features that define them as members of the phylum Chordata. During their brief, free-swimming larval stage, they exhibit the following characteristics shared with other chordates:

Notochord: A stiff, dorsal supporting rod that provides structural support for the tail.123
Dorsal nerve cord: A hollow nerve cord located above the gut.123
Tail: A muscular tail that extends behind the anus, facilitating movement.123

These features are characteristic of the chordate body plan, though in most tunicates, they are resorbed or lost as the larva undergoes metamorphosis into its sessile adult form. While these traits are typically transient in tunicates, they underscore the evolutionary relationship between tunicates and other chordate groups, including vertebrates.1425