''Branchiostoma'' is one of the few living genera of

lancelet The lancelets ( or ), also known as amphioxi (singular: amphioxus ), consist of some 30 to 35 species of "fish-like" benthic filter feeding chordates in the order Amphioxiformes. They are the modern representatives of the subphylum Cephalochord ...

s ( order Amphioxiformes). It is the type genus of

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Branchiostomatidae Branchiostomatidae is a family of lancelets belonging to the class Leptocardii, order unknown. Genera: * ''Asymmetron'' Andrews, 1893 * '' Branchiostoma'' Costa, 1834 * ''Epigonichthys'' Peters, 1876 * '' Epigonopterus'' Jordan & Gilbert, 1882 * ...

These small vaguely eel- or snake-like animals are close relatives of

vertebrate Vertebrates () comprise all animal taxa within the subphylum Vertebrata () (chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, with c ...

s. The scientific name means "gill-mouth", referring to their

anatomy Anatomy () is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old science, having it ...

– unlike vertebrates, they do not have a true head (with a

skull The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, th ...

capsule, eyes,

nose A nose is a protuberance in vertebrates that houses the nostrils, or nares, which receive and expel air for respiration alongside the mouth. Behind the nose are the olfactory mucosa and the sinuses. Behind the nasal cavity, air next passes ...

, a well-developed

brain A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a ve ...

etc.), but merely a mouth adjacent to the

gill A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

-slits, with the slightly enlarged anterior end of the

dorsal nerve cord The dorsal nerve cord is a unique feature to chordates, and it is mainly found in the Vertebrata chordate subphylum. The dorsal nerve cord is only one embryonic feature unique to all chordates, among the other four chordate features-- a notochord, ...

above and in front of them. It dislikes the light. Like all lancelets, they are filter feeders that hide in the

sediment Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sa ...

most of the time. The genus inhabits coastal waters throughout the world.

Species

* '' Branchiostoma africae'' Hubbs, 1927 * '' Branchiostoma arabiae'' Webb, 1957 * '' Branchiostoma bazarutense'' Gilchrist, 1923 * '' Branchiostoma belcheri'' Gray, 1847 (Belcher's lancelet) * ''

Branchiostoma bennetti ''Branchiostoma bennetti'', the mud lancelet, is a lancelet of the genus ''Branchiostoma'' endemic to the Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surro ...

'' Boschung & Gunter, 1966 (Mud lancelet) * '' Branchiostoma bermudae'' Hubbs, 1922 * '' Branchiostoma californiense'' Andrews, 1893 (Californian lancelet) * '' Branchiostoma capense'' Gilchrist, 1902 * '' Branchiostoma caribaea'' Sundevall, 1853 (Caribbean lancelet) * '' Branchiostoma clonasea'' * ''

Branchiostoma elongata ''Branchiostoma'' is one of the few living genus, genera of lancelets (order (biology), order Amphioxiformes). It is the type (zoology), type genus of family (biology), family Branchiostomatidae. These small vaguely eel- or snake-like animals a ...

'' Sundevall, 1852 * '' Branchiostoma floridae'' Hubbs, 1922 (Florida lancelet) * '' Branchiostoma gambiense'' Webb, 1958 * '' Branchiostoma indica'' Willey, 1901 * '' Branchiostoma japonica'' Willey, 1896 (Pacific lancelet) * ''

Branchiostoma lanceolatum ''Branchiostoma lanceolatum'', the European lancelet or Mediterranean amphioxus, is a lancelet in the subphylum Cephalochordata. It is a marine invertebrate with a notochord but no backbone and is used as a model organism to study the evoluti ...

'' Pallas, 1774 (European lancelet) * '' Branchiostoma leonense'' Webb, 1956 * ''

Branchiostoma longirostra ''Branchiostoma'' is one of the few living genera of lancelets ( order Amphioxiformes). It is the type genus of family Branchiostomatidae. These small vaguely eel- or snake-like animals are close relatives of vertebrates. The scientific name ...

'' Boschung, 1983 (Shellhash lancelet) * ''

Branchiostoma malayana ''Branchiostoma'' is one of the few living genera of lancelets (order Amphioxiformes). It is the type genus of family Branchiostomatidae. These small vaguely eel- or snake-like animals are close relatives of vertebrates. The scientific name me ...

'' Webb, 1956 * '' Branchiostoma moretonense'' Kelly, 1966; '' nomen dubium'' * ''

Branchiostoma nigeriense ''Branchiostoma'' is one of the few living genera of lancelets (order Amphioxiformes). It is the type genus of family Branchiostomatidae. These small vaguely eel- or snake-like animals are close relatives of vertebrates. The scientific name me ...

'' Webb, 1955 * ''

Branchiostoma platae ''Branchiostoma'' is one of the few living genera of lancelets (order Amphioxiformes). It is the type genus of family Branchiostomatidae. These small vaguely eel- or snake-like animals are close relatives of vertebrates. The scientific name me ...

'' Hubbs, 1922 * '' Branchiostoma senegalense'' Webb, 1955 * ''

Branchiostoma tattersalli ''Branchiostoma'' is one of the few living genera of lancelets (order Amphioxiformes). It is the type genus of family Branchiostomatidae. These small vaguely eel- or snake-like animals are close relatives of vertebrates. The scientific name me ...

'' Hubbs, 1922 * '' Branchiostoma virginiae'' Hubbs, 1922 (Virginian lancelet)

References

External links

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Branchiostoma
Cephalochordata Taxa named by Oronzio Gabriele Costa Chordate genera {{chordate-stub