Does a cyclostome have a backbone

Answer 1

Cyclostomes are a group of chordates that include the lampreys and the hagfishes. They do not have a true backbone, but instead have blocks of cartiledge, called arcualia, around the spinal cord (similar to what you would find in vertebrate embryos). Taxonimcally, cyclostomes are included in the phylum chordata, subphylum vertebrata. They are considered primitive vertebrates, even though they do not have true vertebrae.