Thaliacea
Pyrosomida
Salpida
Doliolida
</table>
The
Thalicea (also known as
salps) comprise a class of marine animals within the subphylum
Urochordata. Unlike their bottom-dwelling relatives the
ascidians, thaliaceans are free-floating for their entire lifespan. Thaliaceans of the order Pyrosomida are colonial, living in groups that can be over a meter long. Those of the order Doliolida live singly, Salpida live singly or form loosely connected "chains". All of the thaliceans are
filter feeders. They have a barrel-shaped body through which they pump water, propelling them through the sea and from which they extract food.
