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Which three subphyla make up the phylum Chordata?
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Chordate
X-ray fish (Pristella maxillaris), is an example of a chordate with a visible backbone.
The phylum Chordata is composed of three distinct subphyla:
- Vertebrata: Often referred to as vertebrates, this group includes the most highly evolved animals, characterized by a well-developed head and a vertebral column that typically replaces the embryonic notochord.12
- Tunicata (or Urochordata): Commonly known as tunicates, these animals are generally sessile as adults and possess a notochord that is restricted to the tail region.12
- Cephalochordata: Also known as lancelets, these small, fishlike marine invertebrates retain a notochord throughout their entire adult life, which extends the full length of the body.132