subphylum vertebrata การใช้

Taxonomists place lampreys and hagfish in the subphylum Vertebrata of the phylum Chordata, which also includes the invertebrate subphyla Tunicata ( sea-squirts ) and the fish-like Cephalochordata ( lancelets or Amphioxus ).
Hagfish are considered members of the subphylum Vertebrata, because they secondarily lost vertebrae; before this event was inferred from molecular and developmental data, the group Craniata was created by Linnaeus ( and is still sometimes used as a strictly morphological descriptor ) to reference hagfish plus vertebrates.