A chordate is any organism that belongs to the phylum chordata, which mostly consists of the well-known vertebrates. This is a spotted eagle ray. It belongs to the phylum chordata, making it a chordate. The five features that classify chordates are a notochord (a flexible rod), a tail, a dorsal nerve cord, pharyngeal slits (filter-feeding organs), and an endostyle (assists in filter-feeding).
Haylee's Advanced Biology Blog 19-20 