Chordate

Taxonomically, the phylum includes the subphyla Vertebrata, includin mammals, fish, amphibians, reptiles, birds; Tunicata, includin salps an sea squirts; an Cephalochordata, comprisin the lancelets. For a recent concise review o chordate relationships, see Holland, N. D. 2005, Chordates. Curr. Biol. 15: R911-R914.

Chordata Temporal range: Fortunian – Holocene, 535–0 Ma PreЄ Є O S D C P T J K Pg N
The X-ray tetra (Pristella maxillaris) is ane o the few chordates wi a visible backbone. The spinal cord is hoosed within its backbone.
Scientific classification
Kinrick:	Animalia
Superphylum:	Deuterostomia
Phylum:	Chordata Haeckel, 1874

The phylum Hemichordata includin the acorn worms haes been presented as a fowert chordate subphylum, but it nou is uisually treatit as a separate phylum. It, alang wi the echinoderm phylum, includin starnfish, sea urchins, an sea cucumbers an thair kin, is the chordates' closest relatives. Primitive chordates are kent frae at least as early as the Cambrian explosion.

Thare mair nor 75,000 livin species o chordates, aboot hauf o whilk is banie fish o the class osteichthyes. The warld's lairgest ainimal, the blue whaul, an festest ainimal, the peregrine falcon, are chordates.