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Branchiostoma Malayanum
''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. ''Branchiostoma'' grows to lengths of 50 to 60 millimeters in length. 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) *''Branchiosto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Branchiostoma Lanceolatum
''Branchiostoma lanceolatum'', the European lancelet or Mediterranean amphioxus is a lancelet in the Phylum, 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 the form of a 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 Cirrus (biology), 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gill
A gill () is a respiration organ, respiratory organ that many aquatic ecosystem, 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 kept moist. The microscopic structure of a gill presents a large surface area to the external environment. Branchia (: branchiae) is the zoologists' name for gills (from Ancient Greek ). With the exception of some aquatic insects, the filaments and lamella (surface anatomy), lamellae (folds) contain blood or Coelom#Coelomic fluid, coelomic fluid, from which gases are exchanged through the thin walls. The blood carries oxygen to other parts of the body. Carbon dioxide passes from the blood through the thin gill tissue into the water. Gills or gill-like organs, located in different parts of the body, are found in various groups of aquatic animals, including Mollusc, molluscs, crustaceans, insects, fish, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Branchiostoma Caribaeum
''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. ''Branchiostoma'' grows to lengths of 50 to 60 millimeters in length. 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) *'' Branch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Branchiostoma Bennetti
''Branchiostoma bennetti'', the mud lancelet, is a lancelet of the genus ''Branchiostoma'' endemic to the Gulf of Mexico The Gulf of Mexico () is an oceanic basin and a marginal sea of the Atlantic Ocean, mostly surrounded by the North American continent. It is bounded on the northeast, north, and northwest by the Gulf Coast of the United States; on the southw ..., where it is found in the northern part. Description Like other lancelets in the genus ''Branchiostoma'', ''B. bennetti'' occurs in inshore waters where it burrows into sand or muddy sand at depths down to about . The body is laterally flattened and pointed at both ends. It has a long dorsal fin and another fin on its ventral surface, and a caudal fin at the rear end. ''B. bennetti'' differs from other western Atlantic lancelets for having the longest buccal cirri among them. These cirri are further unique in this region because of their extended lateral projections. It is presumed that these unique buccal cirri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Branchiostoma Belcheri
Amphioxus or lancelets (''Branchiostoma'') are members of the Chordata phylum of which all members have a notochord at some point while they are alive. ''B. belcheri'' have a notochord, dorsal nerve cord, pharynx, buccal cavity, cirri, tail, dorsal fin, nerve cord, segmented muscle, and ocelli. They are distinguishable by a slightly round dorsal fin, eighty slender preanal fin-chambers, narrow caudal fin, and obtuse angles between fins. They obtain food by filter feeding. They were first reported in 1897 near the Amakusa Islands, specifically off Goshonoura Island, south of Amakusa-Kamishima Island. These islands are located on the west coast of Kyushu, the island furthest south of the four main isles of Japan. In addition to the location of the siting, information regarding reproductive period and morphology was also obtained. ''B. belcheri'' are gonochoric, reproducing via external fertilization. ''B. belcheri'' are an endangered species, threatened by the influx of pollutants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Branchiostoma Bazarutense
''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. ''Branchiostoma'' grows to lengths of 50 to 60 millimeters in length. 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) *''Branchio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sediment
Sediment is a solid material that is transported to a new location where it is deposited. It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently sediment transport, transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand and silt can be carried in suspension (chemistry), suspension in river water and on reaching the sea bed deposited by sedimentation; if buried, they may eventually become sandstone and siltstone (sedimentary rocks) through lithification. Sediments are most often transported by water (fluvial, fluvial processes), but also wind (aeolian processes) and glaciers. Beach sands and stream channel, river channel deposits are examples of fluvial transport and deposition (geology), deposition, though sediment also often settles out of slow-moving or standing water in lakes and oceans. Desert sand dunes and loess are examples of aeolian transport and deposition. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
