Solution:
Urochordates have notochord present only in larval tail. Ascidia is a urochordate or tunicate.
Polychaetes are annelids and non-chordates.
Balanoglossus is a hemichordate and non-chordate.
Petromyzon is a vertebrate.
Notochord is present only in larval tail among
Urochordates have notochord present only in larval tail. Ascidia is a urochordate or tunicate.
Polychaetes are annelids and non-chordates.
Balanoglossus is a hemichordate and non-chordate.
Petromyzon is a vertebrate.