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Branchiostoma
''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 are close relatives of vertebrates. The scientific name means "gill-mouth", referring to their anatomy – unlike vertebrates, they do not have a true head (with a skull capsule, eyes, nose, a well-developed brain etc.), but merely a mouth adjacent to the gill-slits, with the slightly enlarged anterior end of the dorsal nerve cord above and in front of them. It dislikes the light. Like all lancelets, they are filter feeders that hide in the sediment 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 ben ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 Cephalochordata. Lancelets closely resemble 530-million-year-old ''Pikaia'', fossils of which are known from the Burgess Shale. Zoologists are interested in them because they provide evolutionary insight into the origins of vertebrates. Lancelets contain many organs and organ systems that are closely related to those of modern fish, but in more primitive form. Therefore, they provide a number of examples of possible evolutionary exaptation. For example, the gill-slits of lancelets are used for feeding only, and not for respiration. The circulatory system carries food throughout their body, but does not have red blood cells or hemoglobin for transporting oxygen. Lancelet genomes hold clues about the early evolution of vertebrates: by comparing genes from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Branchiostoma Clonasea
''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 means "gill-mouth", referring to their anatomy – unlike vertebrates, they do not have a true head (with a skull capsule, eyes, nose, a well-developed brain etc.), but merely a mouth adjacent to the gill-slits, with the slightly enlarged anterior end of the dorsal nerve cord above and in front of them. It dislikes the light. Like all lancelets, they are filter feeders that hide in the sediment 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'' Boschung & Gunter, 1966 (Mud lancelet) * '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Branchiostoma Africae
''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 means "gill-mouth", referring to their anatomy – unlike vertebrates, they do not have a true head (with a skull capsule, eyes, nose, a well-developed brain etc.), but merely a mouth adjacent to the gill-slits, with the slightly enlarged anterior end of the dorsal nerve cord above and in front of them. It dislikes the light. Like all lancelets, they are filter feeders that hide in the sediment 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'' Boschung & Gunter, 1966 (Mud lancelet) * ''Bran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Branchiostoma Anatomy
''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 means "gill-mouth", referring to their anatomy – unlike vertebrates, they do not have a true head (with a skull capsule, eyes, nose, a well-developed brain etc.), but merely a mouth adjacent to the gill-slits, with the slightly enlarged anterior end of the dorsal nerve cord above and in front of them. It dislikes the light. Like all lancelets, they are filter feeders that hide in the sediment 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'' Boschung & Gunter, 1966 (Mud lancelet) * ''Branch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Branchiostoma Arabiae
''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 means "gill-mouth", referring to their anatomy – unlike vertebrates, they do not have a true head (with a skull capsule, eyes, nose, a well-developed brain etc.), but merely a mouth adjacent to the gill-slits, with the slightly enlarged anterior end of the dorsal nerve cord above and in front of them. It dislikes the light. Like all lancelets, they are filter feeders that hide in the sediment 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'' Boschung & Gunter, 1966 (Mud lancelet) * ''Bra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 evolutionary development of vertebrates. Anatomy ''Branchiostoma lanceolatum'' has an elongated body, flattened laterally and pointed at both ends. A stiffening rod of tightly packed cells, the notochord, extends the whole length of the body. Unlike vertebrates, the notochord persists in the adult, in form of simple dorsal neural tube slightly thickened in the anterior part (the cerebral vesicle). Above it is a nerve cord with a single frontal eye. The mouth is on the underside of the body and is surrounded by a tuft of 20 or 30 cirri or slender sensory appendages. The gut runs just below the notochord from the mouth to the anus, in front of the tail. There is a flap-like, vertical fin surrounding the pointed tail. Gas exchange takes place as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
