#notochord structure

• Amphioxus — The common or historical scientific name (genus Amphioxus) used in zoology to designate the lancelet (scientifically known as Branchiostoma lanceolatum), a small, translucent, lance-shaped marine invertebrate belonging to the Chordata phylum (subphylum Cephalochordata). It represents a fundamental reference organism in the study of comparative anatomy and vertebrate evolution, as it retains a simple structural dorsal notochord throughout its entire life cycle without developing a bony vertebral column.
• Amphioxus — A small marine animal with a translucent body, pointed at both ends, lacking a skull, vertebrae, and limbs, belonging to the chordate phylum, subphylum Cephalochordata (Branchiostoma lanceolatum). Structurally, the animal possesses a permanent notochord throughout its lifespan, representing a key link in the evolutionary study of vertebrate comparative anatomy.