The cephalochordates are the closest living relatives of the vertebrates. The group derives its name from the notochord that extends far forward into the head (farther than the brain, in contrast to vertebrates). The most famous representative of the...

The lancelets (subphylum Cephalochordata, traditionally known as amphioxus) are a group of primitive chordates. They are usually found buried in sand in shallow parts of temperate or tropical seas. In Asia, they are harvested commercially for food that...

Larvae of lancelets (=amphioxus) are of special interest because they figure prominently in debates about vertebrate origins (1), can sometimes grow into a giant "amphioxides" form (2, 3), have a puzzling right-left asymmetry (4), and constitute a major zooplankton resource in parts of the...