Is amphioxus a lancelet?
amphioxus, plural amphioxi, or amphioxuses, also called lancelet, any of certain members of the invertebrate subphylum Cephalochordata of the phylum Chordata. Amphioxi are small marine animals found widely in the coastal waters of the warmer parts of the world and less commonly in temperate waters.
Do lancelets have myomeres?
A significant feature of lancelets, which is shared with vertebrates but not tunicates, is the presence of myomeres. Myomeres are repeating units, or blocks, of muscle that partially overlap to form a row along the body of the animal, as shown in Figure below.
What is the function of the myomeres in the amphioxus?
Function. Specifically, three types of myomeres in fish-like chordates include amphioexine (lancelet), cyclostomine (eel), and piscine (fish). A common function shared by all of these is that they function to flex the body laterally into concavity to provide force for locomotion.
Is a lancelet a vertebrate?
Cephalochordates, commonly called amphioxus or lancelets, are marine invertebrate chordates. They were traditionally held as the closest living relatives of vertebrates and have long occupied a key phylogenetic position in our discussions on the origin of vertebrates.
Is a lancelet a fish?
The lancelet is a small, translucent, fish-like animal that is one of the closest living invertebrate relatives of the vertebrates.
What do myomeres do?
There are three distinct types of myomeres: amphioxine, cyclostomine and piscine. All have in common the function of bending their possessors’ bodies from side to side to provide locomotor force. In all cases pull is applied obliquely to the long axis of the body.
What are myomeres and Myosepta?
bundles of muscle fibres called myomeres. The myomeres are separated by thin horizontal (myosepta) and vertical (myocommata) layers of connective tissue. The unique structure and thin connective tissue sheaths of fish muscle give the meat its characteristic soft, flaky texture.
What is lancelet shape?
noun. any of several small, lancet-shaped burrowing marine animals of the subphylum Cephalochordata, having a notochord and bearing structural similarities to both vertebrates and invertebrates.
What phylum is a lancelet?
ChordateLancelet / Phylum