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Which groups of animals are included among tunicates?
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Chordate
X-ray fish (Pristella maxillaris), is an example of a chordate with a visible backbone.
Tunicates, which belong to the subphylum Tunicata (or Urochordata) within the phylum Chordata, are categorized into three distinct classes based on their structure and lifestyle:12
- Ascidiacea (Ascidians or sea squirts): These are primarily benthic, sessile animals that can exist as solitary individuals or in colonies. They are known for their protective outer covering, or tunic, and their role in biomedicine due to the natural products they produce.23
- Appendicularia (Larvacea): These small, pelagic animals retain their larval features throughout adulthood. They are unique for building a protective "house" used to filter food from the open sea.12
- Thaliacea: This class includes pyrosomes, dolioloids, and salps. These are pelagic organisms that appear to be ascidians adapted for life in open water, often exhibiting complex reproductive cycles involving both sexual and asexual phases.2