A small lancelet which is caught for food in parts of Asia.
Genus Branchiostoma (formerly Amphioxus), family Branchiostomidae.
Thus amphioxus is the only chordate species in which distinct insulin and IGF genes have not been found....
Organisms along the lines of the cephalochordate amphioxus use the gill apparatus for filter feeding.
The cephalochordate amphioxus is the closest living invertebrate relative of the vertebrates and therefore the best model organism for understanding the composition of the ancestral chordate genome.
Origin
Mid 19th century: modern Latin, from amphi- + Greek oxus 'sharp'.