樽海鞘纲是尾索动物亚门的一个纲。现存65种。体成桶形，单体或群体营飘浮生活。被囊薄而透明，其上有环状肌肉带。例如樽海鞘。

The Thaliacea comprise a class of marine animals within the subphylum Tunicata. Unlike their benthic relatives the ascidians, thaliaceans are free-floating (pelagic) for their entire lifespan. The group includes species with complex life cycles with both solitary and colonial forms.