A subclass of cartilaginous fish comprising the SHARKS; rays; skates (SKATES (FISH);), and sawfish. Elasmobranchs are typically predaceous, relying more on smell (the olfactory capsules are relatively large) than sight (the eyes are relatively small) for obtaining their food.
The common name for all members of the Rajidae family. Skates and rays are members of the same order (Rajiformes). Skates have weak electric organs.
Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)
A group of elongate elasmobranchs. Sharks are mostly marine fish, with certain species large and voracious.
NATIONAL LIBRARY OF MEDICINE service for health professionals and consumers. It links extensive information from the National Institutes of Health and other reviewed sources of information on specific diseases and conditions.
One of a set of bone-like structures in the mouth used for biting and chewing.
A group of cold-blooded, aquatic vertebrates having gills, fins, a cartilaginous or bony endoskeleton, and elongated bodies covered with scales.
Sharks of the family Squalidae, also called dogfish sharks. They comprise at least eight genera and 44 species. Their LIVER is valued for its oil and its flesh is often made into fertilizer.
A species of shark in the family SQUALIDAE, used for its oil (SQUALENE) and as fish meal. It also figures heavily in biological research, especially with reference to its RECTAL GLAND in studies of WATER-ELECTROLYTE BALANCE.
The most diversified of all fish orders and the largest vertebrate order. It includes many of the commonly known fish such as porgies, croakers, sunfishes, dolphin fish, mackerels, TUNA, etc.
Organic chemistry methodology that mimics the modular nature of various biosynthetic processes. It uses highly reliable and selective reactions designed to "click" i.e., rapidly join small modular units together in high yield, without offensive byproducts. In combination with COMBINATORIAL CHEMISTRY TECHNIQUES, it is used for the synthesis of new compounds and combinatorial libraries.
Diseases of freshwater, marine, hatchery or aquarium fish. This term includes diseases of both teleosts (true fish) and elasmobranchs (sharks, rays and skates).
Oils high in unsaturated fats extracted from the bodies of fish or fish parts, especially the LIVER. Those from the liver are usually high in VITAMIN A. The oils are used as DIETARY SUPPLEMENTS. They are also used in soaps and detergents and as protective coatings.
Food products manufactured from fish (e.g., FISH FLOUR, fish meal).
Hydrocarbons with at least one triple bond in the linear portion, of the general formula Cn-H2n-2.
Proteins obtained from species of fish (FISHES).
Class of parasitic flukes consisting of three subclasses, Monogenea, Aspidogastrea, and Digenea. The digenetic trematodes are the only ones found in man. They are endoparasites and require two hosts to complete their life cycle.
Infections caused by infestation with worms of the class Trematoda.
Encysted cercaria which house the intermediate stages of trematode parasites in tissues of an intermediate host.
Maintenance of the hygienic state of the skin under optimal conditions of cleanliness and comfort. Effective in skin care are proper washing, bathing, cleansing, and the use of soaps, detergents, oils, etc. In various disease states, therapeutic and protective solutions and ointments are useful. The care of the skin is particularly important in various occupations, in exposure to sunlight, in neonates, and in PRESSURE ULCER.
The relationship between an invertebrate and another organism (the host), one of which lives at the expense of the other. Traditionally excluded from definition of parasites are pathogenic BACTERIA; FUNGI; VIRUSES; and PLANTS; though they may live parasitically.
City, urban, rural, or suburban areas which are characterized by severe economic deprivation and by accompanying physical and social decay.
The study of animals - their morphology, growth, distribution, classification, and behavior.
Instinctual behavior pattern in which food is obtained by killing and consuming other species.
A muscular organ in the mouth that is covered with pink tissue called mucosa, tiny bumps called papillae, and thousands of taste buds. The tongue is anchored to the mouth and is vital for chewing, swallowing, and for speech.
Bony structure of the mouth that holds the teeth. It consists of the MANDIBLE and the MAXILLA.
Animals having a vertebral column, members of the phylum Chordata, subphylum Craniata comprising mammals, birds, reptiles, amphibians, and fishes.
Tumors or cancer of the TONGUE.
The oval-shaped oral cavity located at the apex of the digestive tract and consisting of two parts: the vestibule and the oral cavity proper.
A congenital anomaly of the hand or foot, marked by the presence of supernumerary digits.
The farthest or outermost projections of the body, such as the HAND and FOOT.
A front limb of a quadruped. (The Random House College Dictionary, 1980)
Small pumps, often implantable, designed for temporarily assisting the heart, usually the LEFT VENTRICLE, to pump blood. They consist of a pumping chamber and a power source, which may be partially or totally external to the body and activated by electromagnetic motors.
The relationships of groups of organisms as reflected by their genetic makeup.
Membranous appendage of fish and other aquatic organisms used for locomotion or balance.
Distinct regions of mesenchymal outgrowth at both flanks of an embryo during the SOMITE period. Limb buds, covered by ECTODERM, give rise to forelimb, hindlimb, and eventual functional limb structures. Limb bud cultures are used to study CELL DIFFERENTIATION; ORGANOGENESIS; and MORPHOGENESIS.
The relationships between symbols and their meanings.
The science of language, including phonetics, phonology, morphology, syntax, semantics, pragmatics, and historical linguistics. (Random House Unabridged Dictionary, 2d ed)
Enzymes that catalyze the joining of glutamine-derived ammonia and another molecule. The linkage is in the form of a carbon-nitrogen bond. EC 6.3.5.
The comparative study of animal structure with regard to homologous organs or parts. (Stedman, 25th ed)
A characteristic showing quantitative inheritance such as SKIN PIGMENTATION in humans. (From A Dictionary of Genetics, 4th ed)
Computer processing of a language with rules that reflect and describe current usage rather than prescribed usage.

Intercellular bridges between granulosa cells and the oocyte in the elasmobranch Raya asterias. (1/59)

In the present ultrastructural study intercellular bridges, connecting somatic granulosa cells to oocyte, have been detected for the first time and their modifications have been followed during Raja oogenesis. Intercellular bridges make their first appearance in small previtellogenic follicles as connecting devices between small cells and the oocyte. Later on, when the follicular epithelium becomes polymorphic and multilayered, for the presence of small, large, and pyriform-like cells, intercellular bridges link the oocyte and the different granulosa cells. Intercellular bridges contain ribosomes, whorl of membranes, mitochondria and vacuoles. Such cytoplasmic components are present also in the cell apex of large and pyriform-like cells thus suggesting, in agreement with other species (Motta et al. J. Exp. Zool., 1996;276:223-241) they may flow toward the oocyte. In this regard the presence of intercellular bridges during the oogenesis of cartilagineous fish may represent a crucial event of the active cooperation between granulosa cells and the oocyte.  (+info)

Retropositional parasitism of SINEs on LINEs: identification of SINEs and LINEs in elasmobranchs. (2/59)

Some previously unidentified short interspersed repetitive elements (SINEs) and long interspersed repetitive element (LINEs) were isolated from various higher elasmobranchs (sharks, skates, and rays) and characterized. These SINEs, members of the HE1 SINE family, were tRNA-derived and were widespread in higher elasmobranches. The 3'-tail region of this SINE family was strongly conserved among elasmobranchs. The LINEs, members of the HER1 LINE family, encoded an amino acid sequence similar to that encoded by the chicken CR1 LINE family, and they contained a strongly conserved 3'-tail region in the 3' untranslated region. This tail region of the HER1 LINE family was almost identical to that of the HE1 SINE family. Thus, the HE1 SINE family and the HER1 LINE family provide a clear example of a pair of SINEs and LINEs that share the same tail region. Conservation of the secondary structures of the tail regions, as well as of the nucleotide sequences, between the HE1 SINE family and HER1 LINE family during evolution suggests that SINEs utilize the enzymatic machinery for retroposition of LINEs through the recognition of higher-order structures of the conserved 3'-tail region. A discussion is presented of the parasitism of SINEs on LINEs during the evolution of these retroposons.  (+info)

The synaptic vesicle protein SV2 is complexed with an alpha5-containing laminin on the nerve terminal surface. (3/59)

Interactions between growing axons and synaptic basal lamina components direct the formation of neuromuscular junctions during nerve regeneration. Isoforms of laminin containing alpha5 or beta2 chains are potential basal lamina ligands for these interactions. The nerve terminal receptors are unknown. Here we show that SV2, a synaptic vesicle transmembrane proteoglycan, is complexed with a 900-kDa laminin on synaptosomes from the electric organ synapse that is similar to the neuromuscular junctions. Although two laminins are present on synaptosomes, only the 900-kDa laminin is associated with SV2. Other nerve terminal components are absent from this complex. The 900-kDa laminin contains an alpha5, a beta1, and a novel gamma chain. To test whether SV2 directly binds the 900-kDa laminin, we looked for interaction between purified SV2 and laminin-1, a laminin isoform with a similar structure. We find SV2 binds with high affinity to purified laminin-1. Our results suggest that a synaptic vesicle component may act as a laminin receptor on the presynaptic plasma membrane; they also suggest a mechanism for activity-dependent adhesion at the synapse.  (+info)

Low mass-specific brain Na+/K+-ATPase activity in elasmobranch compared to teleost fishes: implications for the large brain size of elasmobranchs. (4/59)

Elasmobranch fishes have long been noted for having unusually large brains for ectotherms, and therefore may be exceptions to the rule that vertebrates in general devote less than 8% of their resting metabolic rate to the central nervous system. The brain mass of sharks, skates and rays is often several times larger than that of teleost fishes of the same size. Still, the underlying reasons for this have remained unclear. Ion pumping by the Na+/K+-ATPase is the single most energy consuming process in the brain. In this study, Na+/K+-ATPase activity was measured in the brain of four species of elasmobranchs and 11 species of teleosts. While the average brain mass of the elasmobranchs examined was approximately three times that of the teleosts, the mean specific Na+/K+-ATPase activity was only about one-third of that of the teleosts. Thus, the total brain Na+/K+-ATPase activity was similar in elasmobranchs and teleosts. This suggests that the large brain size of elasmobranchs is at least partly related to a low mass-specific rate of brain energy use.  (+info)

The pit organs of elasmobranchs: a review. (5/59)

Elasmobranchs have hundreds of tiny sensory organs, called pit organs, scattered over the skin surface. The pit organs were noted in many early studies of the lateral line, but their exact nature has long remained a mystery. Although pit organs were known to be innervated by the lateral line nerves, and light micrographs suggested that they were free neuromasts, speculation that they may be external taste buds or chemoreceptors has persisted until recently. Electron micrographs have now revealed that the pit organs are indeed free neuromasts. Their functional and behavioural role(s), however, are yet to be investigated.  (+info)

Detection and processing of electromagnetic and near-field acoustic signals in elasmobranch fishes. (6/59)

The acoustic near field of quietly moving underwater objects and the bio-electric field of aquatic animals exhibit great similarity, as both are predominantly governed by Laplace's equation. The acoustic and electrical sensory modalities thus may, in directing fishes to their prey, employ analogous processing algorithms, suggesting a common evolutionary design, founded on the salient physical features shared by the respective stimulus fields. Sharks and rays are capable of orientating to the earth's magnetic field and, hence, have a magnetic sense. The electromagnetic theory of orientation offers strong arguments for the animals using the electric fields induced by ocean currents and by their own motions in the earth's magnetic field. In the animal's frame of reference, in which the sense organs are at rest, the classical concept of motional electricity must be interpreted in relativistic terms. In the ampullae of Lorenzini, weak electric fields cause the ciliated apical receptor-cell membranes to produce graded, negative receptor currents opposite in direction to the fields applied. The observed currents form part of a positive-feedback mechanism, supporting the generation of receptor potentials much larger than the input signal. Acting across the basal cell membranes, the receptor potentials control the process of synaptic transmission.  (+info)

Contractile properties of the elasmobranch rectal gland. (7/59)

The importance of the rectal gland in elasmobranch osmoregulation is well established. The rate of secretion by the gland is under the control of a variety of secretagogues and inhibitors. Early morphological work suggested that a band of smooth muscle cells surrounds the periphery of the shark rectal gland between the secretory tubules and the connective tissue capsule. To confirm the presence of the muscle ring, we examined histological sections from two species of shark, Squalus acanthias and Carcharodon carcharius, and from the stingray Dasyatis sabina and stained sections from S. acanthias with the actin-specific ligand phalloidin. In all three species, a distinct band of what appeared to be smooth muscle cells was evident, and the putative muscle ring in S. acanthias stained specifically with phalloidin. Moreover, isolated rings of rectal gland tissue from S. acanthias constricted when acetylcholine or endothelin was applied and responded to nitric oxide with an initial dilation, followed by a more substantial constriction. Subsequent addition of porcine C-type natriuretic peptide dilated the rings, but two prostanoids (carbaprostacyclin and prostaglandin E(1)) did not change ring tension significantly. The rings did not respond to the endothelin-B-specific agonist sarafotoxoin S6c, suggesting that the response to endothelin was mediated via endothelin-A-type receptors. Our data confirm the presence of a smooth muscle ring in the periphery of the elasmobranch rectal gland and demonstrate that the gland responds to a suite of smooth muscle agonists, suggesting that changes in the dimensions of the whole rectal gland may play a role in its secretory function.  (+info)

Digenea and acanthocephala of elasmobranch fishes from the southern coast of Brazil. (8/59)

New records for helminth species recovered from elasmobranch fishes in Brazil are established. Digenean and acanthocephalan parasites of elasmobranch fishes are reported from the southern coast of Brazil: Otodistomum veliporum (Creplin, 1837) Stafford, 1904 (Digenea: Azygiidae) in the stomach and spiral valve of Dipturus trachydermus and in the spiral valve of Squatina sp. Cystacanths and juveniles of the acanthocephalans Corynosoma australe Johnston, 1937 and Corynosoma sp., in the spiral valve of Squatina sp., Galeorhinus galeus and Hexanchus griseus and in the stomach of Squalus megalops; a juvenile of Gorgorhynchus sp., in the spiral valve of Sphyrna zygaena. Dipturus trachydermus and Squatina sp. are new host records for O. veliporum. Digeneans and acanthocephalans are reported for the first time parasitizing elasmobranch fishes in Brazil.  (+info)

Other articles where Smalltooth sawfish is discussed: sawfish: In 2015 the smalltooth sawfish (P. pectinata) was observed to have the ability to reproduce via parthenogenesis (a condition in which an unfertilized egg develops into an embryo). The species was one of the first vertebrate groups found to be capable of parthenogenesis in the wild. The strategy…
Background The trade in manta ray gill plates has considerably increased over the last two decades. The resulting increases in ray mortality, in addition to mortality caused by by-catch, has caused many ray populations to decrease in size. The aim of this study was to ascertain how yearling and juvenile growth and survival, and adult survival and reproduction affect reef manta ray (Manta alfredi) population change, to increase our understanding of manta ray demography and thereby improve conservation research and measures for these fish. Methods We developed a population projection model for reef manta rays, and used published life history data on yearling and juvenile growth and adult reproduction to parameterise the model. Because little is known about reef manta ray yearling and juvenile survival, we conducted our analyses using a range of plausible survival rate values for yearlings, juveniles and adults. Results The model accurately captured observed variation in population growth rate, lifetime
Sawfish are marine shark-like cartilaginous fish in the family Pristidae in order Rajiformes. Sawfish are characterized by their long snout nose which has sharp teeth on each side. Like other rays, sawfish lurk to attack schools of prey fish with its long snout, and devour the injured fish. The long snout also serves as a defensive weapon, inflicting serious injury on any enemy attacking it. Sawfish have gill slits on the undersurface of the body on both sides, posterior to the mouth, as in other rays.. Sawfish are generally found in shallow waters in tropical seas, with some species occurring in brackish or fresh water. A population of sawfish lives in Lake Nicaragua, completely separated from the sea. Sawfish can grow to large sizes. The small tooth sawfish, Pristits pectinata averages 15 ft (5 m) in length, and specimens have been found up to 20 ft (6 m) long and weighing 800 lb (360 kg). This species lives in the warm waters of the Atlantic from the Mediterranean to Africa and across the ...
Common Names: Freshwater Sawfish, Largetooth Sawfish, Broadbill Sawfish.. Latin Name: Pristis microdon. Family: Pristidae. Identification: Overall flattened sharklike body. Elongated flattened rostrum (saw) with 18 to 23 pairs of evenly spaced rostral teeth. Anterior pair of rostral teeth angled forward. Base of rostrum wide hence vernacular: Broadbill Sawfish. First dorsal fin originates in front of pelvic fins. Distinct lower caudal lobe.. Size: Maximum length 5m. At birth approx 50cm.. Habitat: Sand and mud bottoms in mildly saline estuaries, rivers, and lagoons. Freshwater Sawfish is a misnomer. It spends its first 3-4 years in freshwater growing to about half its adult size. Adults penetrate from weakly saline estuaries into fresh water rivers(up to 100km from the sea) . Individual sawfish may be cut off in small ponds for years at a time between floods. In Australia it is confined to large freshwater river drainages.. Abundance and distribution: Considered critically endangered by the IUCN ...
The Tiger Shovelnose Catfish (Pseudoplatystoma fasciatum) also known by tropical fish keeping enthusiasts as the Tiger Catfish, is found in various rivers and tributaries in South America. It prefers deeper waters in the main river channels but can be found in lakes, flooded forests and other freshwater areas.. The Tiger Shovelnose Catfish is long and slender with a beautiful silver coloration over its entire body. Its body is covered with black stripes and spots which give the fish a tiger like appearance, hence its name.. The Tiger Shovelnose Catfish has a long flat shaped mouth that is adorned with very long whiskers.. These catfish grow quite large in captivity (over 3 feet) and require at least a 180 gallon aquarium to keep them happy and healthy. They are active and should have a tight fitting tank cover to prevent them from jumping out of their tank.. ...
SUMMARY The critical O 2 tension of whole-animal O 2 consumption rate ( ), or P crit , is the water P O2 ( P w O 2 ) at which an animal transitions from an oxyregulator to an oxyconformer. Although P crit is a popular measure of hypoxia tolerance in fishes because it reflects the capacity for O 2 uptake from the environment at low P w O 2 , little is known about the interrelationships between P crit and blood O 2 transport characteristics and increased use of anaerobic metabolism during hypoxia exposure in fishes, especially elasmobranchs. We addressed this knowledge gap using progressive hypoxia exposures of two elasmobranch species with differing hypoxia tolerance. The P crit of the hypoxia-tolerant epaulette shark ( Hemiscyllium ocellatum , 5.10±0.37 kPa) was significantly lower than that of the comparatively hypoxia-sensitive shovelnose ray ( Aptychotrema rostrata , 7.23±0.40 kPa). Plasma [lactate] was elevated above normoxic values at around P crit in epaulette sharks, but increased ...
Purchase Physiology of Elasmobranch Fishes: Structure and Interaction with Environment, Volume 34A - 1st Edition. Print Book & E-Book. ISBN 9780128012895, 9780128014431
ABSTRACT: Sightings of planktivorous elasmobranchs at their coastal aggregation sites are often linked to biological, environmental and temporal variables. Many large planktivorous elasmobranchs are also globally threatened species, so it is necessary to try and separate population trends from environmentally driven, short-term fluctuations. We investigated the influence of environmental variables on sightings of 3 species of planktivorous elasmobranchs off Praia do Tofo, Mozambique: the reef manta ray Manta alfredi, giant manta ray M. birostris and whale shark Rhincodon typus. We used 8- (2003 to 2011) and 6-yr (2005 to 2011) logbook data for manta rays and whale sharks, respectively, and constructed a generalised linear model with animal sightings as the response. Predictors included temporal (year, month, time of day), biological (plankton categories), oceanographic (water temperature, time from high tide, current direction and strength and wave height) and celestial (moon illumination) ...
Marine elasmobranchs such as shark, dogfish and rays overcome their osmotic difficulties in a unique way. They have a similar chloride....
I was at the pet store the other day and they had about an 8 inch shovelnose for sale. My question is does this fish require a heater? I have a blue channel cat and a golden bulkhead in with other native lake species in a 150g but I dont run a heater. I asked the lady there and she told me the tank it was in was 80 degrees so it must reguire warm water.
I was at the pet store the other day and they had about an 8 inch shovelnose for sale. My question is does this fish require a heater? I have a blue channel cat and a golden bulkhead in with other native lake species in a 150g but I dont run a heater. I asked the lady there and she told me the tank it was in was 80 degrees so it must reguire warm water.
The elasmobranchs (sharks, rays and skates) being the extant survivors of one of the earliest offshoots of the vertebrate evolutionary tree are good model organisms to study the primitive vertebrate conditions. They play a significant role in maintaining the ecological balance and have high economic value. Due to over-exploitation and illegal fishing worldwide, the elasmobranch stocks are being decimated at an alarming rate. Appropriate management measures are necessary for restoring depleted elasmobranch stocks. One approach for restoring stocks is implementation of conservation measures and these measures can be formulated effectively by knowing the evolutionary relationship among the elasmobranchs. In this study, a total of 30 species were chosen for molecular phylogeny studies using mitochondrial cytochrome c oxidase subunit I, 12S ribosomal RNA gene and nuclear Internal Transcribed Spacer 2. Among different genes, the combined dataset of COI and 12S rRNA resulted in a well resolved tree topology
According to wildlife charities, between 3,500 to 5,000 manta rays are killed each year for their gills.. A fisherman in Asia is able to make up to $40 for each Manta ray gill that he sells. The dried gills end up in China being sold for up to $2,000.. The estimated value of the illegal trade in Manta rays is between $5 Million to $10 Million a year. In areas where the Manta ray are living, the economic value of the species to the tourism industry is worth $100 Million.. In the waters off of Indonesia, the population of Manta rays has declined by 56 percent. In Sri Lanka, the population has declined by 86 percent.. Source: Damian Carrington, Manta rays: how illegal trade eats its own lunch, Guardian, Environment Blog, March 5, 2013.. ...
The aim of this study was to describe two epizootics of high mortalities from infection with Streptococcus agalactiae, occurring in captive rays held in a marine display aquarium in south-east Queensland, Australia, in 2009 and 2010. Five different species of rays were affected, including mangrove whiprays (Himantura granulata), estuary rays (Dasyatis fluviorum), eastern shovelnose rays (Aptychotrema rostrata), white-spotted eagle rays (Aetobatus narinari) and blue-spotted mask rays (Neotrygon kuhlii). This report describes the history of both epizootics including collection, quarantine and husbandry of rays, the disease epizootics, clinico-pathological features of the disease, antimicrobial therapy, autogenous vaccine production, and laboratory studies including clinical and histopathology, bacteriology, PCR, molecular serotyping and sequencing of the bacterium S. agalactiae.. ...
Ceca Manta Manta Lyrics. Manta Manta lyrics performed by Ceca: Manta, manta, manta sve mi se manta kad vidim te manta, manta, manta da li i tebi manta se Neke ljubavi prolaze neke nikad da se dese ova moja fenomen je ko jos moze da podnese da voli samo tog s kim nije nasamo Ref. Obavezno dodji sam dodji mi na noc, dodji mi na dan obavezno dodji sam dodji mi na stan, dodji mi na dlan Sedam bi od osam bi zena reklo ti reklo zbogom, kraj sedam bi od osam bi reklo bi, mi, bi al ja sam osma, znaj Neke ljubavi su vecne neke jedna noc odnese ova moja fenomen je ko jos moze da podnese da voli samo tog s kim nije nasamo Ref. Manta, manta, manta sve mi se manta kad vidim te manta, manta, manta da li i tebi manta se Ref.
From a school girl who didnt like biology, Barbara is now a passionate scientist whose experiments show how sensitive sawfish are to electric fields and where a sawfish can detect them.. Right now, I am working on ... Several publications. After writing up my research outcomes in my thesis, it is now important to get these chapters published. Some of the work on sawfish senses is in print right now, while other behavioural work with sawfish will be published soon!. A typical day is ... There is no typical day for me. Sometimes I spend days in the laboratory dissecting sawfish and other sharks and rays that were accidentally caught in fishing gear. Other days I am out in the field taking measurements of the environment that my study animals live in. And there are days when I do experiments with animals in tanks. That research has to be analysed later (which means hours of watching the footage and taking measurements from it, and then analysing it statistically), and written up. On days when I do ...
Elasmobranch definition, belonging or pertaining to the Elasmobranchii, the subclass of cartilaginous fishes comprising the sharks and rays. See more.
A living Shovelnose Ray is identical to a Jurassic fossil ray, a living fossil, bringing into question both evolution and geological time.
Description, classification, synonyms, distribution map, bibliography and images of Aptychotrema rostrata - East Australian shovelnose ray
The table of contents of Biology of Sharks and Their Relatives is the first indication that this books editors succeeded in their objective of compiling far more than just another book about the biology of the Class Chondrichthyes (sharks, rays, and chimeras). It is the scope of this book that distinguishes it. Its subjects include natural history, zoogeography and evolutionary relationships, and diverse aspects of mainly elasmobranch (sharks and rays) functional morphology and physiology. Biology of Sharks and Their Relatives is, moreover, a primer for the science and technology required for the development of strategies for conserving these organisms in the face of over-fishing and habitat destruction.. Divided into three sections, this volume contains 19 chapters, each authored by active participants in the disciplines about which they write. The books first section, Phylogeny and Zoogeography, chronicles chondrichthyan relationships, biology and distribution. Although the chimeras occur ...
Occurs in the bottom of main channels and embayments of large turbid rivers; frequently in flowing water over sand and mixed with gravel and mud. Feeds primarily on larvae of aquatic insects (especially burrowing mayflies, caddis larvae and midge larvae (Ref. 10294)), worms, and crustaceans (Ref. 50937). Spawning occurs from April to June in large rivers in areas of swift current and coarse substrates (Ref. 10294). ...
The interaction of multiple physiological and ecological factors probably explains why chondrichthyans are rare in the abyss. Three leading hypotheses have emerged, all of which implicate major roles for physiological mechanisms and none of which are mutually exclusive. First, the chondrichthyan osmoregulatory system may limit abyssal penetration as a result of the inability to balance stabilizing and destabilizing influences of pressure and osmolytes on proteins, and/or through the interactive effects of temperature, pressure and urea on membranes. Second, the reliance on lipid-based buoyancy has a unique energetic cost that could increasingly limit growth rate and reproductive output as oligotrophy intensifies with depth. Third, chondrichthyans may be unusually nutrient limited in the oligotrophic abyss because of their nitrogen-intensive osmoregulatory strategy combined with inherent, unavoidable nitrogen losses at their gills.. The first hypothesis, which involves an abiotic factor ...
Some new and little known cestodes from Australian elasmobranchs with a brief discussion on their possible use in problems of host taxonomy - Volume 54 Issue 4 - H. Harford Williams
The natural coloration and body pigmentation of manta rays has been considered permanent over their lifespan. Recently, a new discovery published in the Biological Journal of The Linnean Society by Dr. Csilla Ari, describes rapid and long-term body pigmentation changes on manta rays. Individual manta rays are identified from patterns of ventral markings worldwide and the body coloration of manta rays is used for species identification as well.. The rapid coloration changes occured within minutes on the head and on the dorsal side of the manta rays during feeding times and during intense social interaction. The exact role and mechanism of these changes are still unknown, but it is very likely that it might serve as a form of communication between the animals.. ...
Among the birds, reptiles, sharks, and now rays, parthenogenesis is thought to be triggered by an unfertilized egg absorbing a sister cell called the polar body that is nearly genetically identical to the egg. This results in an offspring that has roughly half the genetic diversity of its mother. In many cases these offspring are malformed or die early. There was a general feeling that vertebrate parthenogenesis was a curiosity that didnt usually lead to viable offspring, said Dr. Gregg Poulakis of the Florida Fish and Wildlife Conservation Commission, who led field collections of the sawfish. The seven parthenogens we found looked to be in perfect health and were normal size for their age. This suggests parthenogenesis is not a reproductive dead end, assuming they grow to maturity and reproduce. The parthenogen sawfish were all tagged and released back into the wild as part of an ongoing study of sawfish biology and ecology. ...
The three of us caught the current and drifted along the outside of the reef, slowly beginning our ascent until, far below, something caught my eye. After a few moments, I made out the white shoulder patches of a manta ray in about one hundred and twenty feet of water. Manta rays are one of my greatest loves, but very little is known about them. They feed on plankton, which makes them more delicate than an aquarium can handle. They travel the oceans and are therefore a mystery. Mantas can be identified by the distinctive pattern on their belly, with no two rays alike.
On Monday 28 December 2009 23:07:52 Christopher Roy Bratusek wrote: , It is autogenerated, were just discussing the fallback, if kde4 is , not installed. debian/sawfish.install is not autogenerated and is now out of sync with the autogenerated Makefiles. Hence dpkg-buildpackage -b fails because it expects usr/share/apps/ksmserver/windowmanagers/sawfish.desktop to be built. The simplest fix is to edit the correct filename into debian/sawfish.install by hand. , err, forgot to commit/push. OK, looks good now. -- Timo Korvola ,URL:http://www.iki.fi/tkorvola ...
Stock Photo of Manta Rays at cleaning station. High Quality Giant Oceanic Manta Ray Images and Gloss Prints are available from Oceanwide Images Stock Photo Library.
Download Free Full-Text of an article ANNUAL REPRODUCTION CYCLE OF MALE TALAL FISH (RASTRELLIGER KANAGURTA) IN SOUTHERN COAST OF IRAN
This order includes the Sharks, Rays, and Chimaerae, and corresponds with the greater and most typical portion of the Chondropterygidae or Cartilaginous fishes of Cuvier. The order is distinguished by...
In the future, youll simply jump into your car, turn on the Internet, turn on a movie and sit back and relax and turn on the automatic pilot, and the car will drive itself, says Michiko Kaku in his book Physics of the Future. Unlike a human driver, it doesnt get drunk, it doesnt get distracted and certainly does not have road rage.. Even though driverless cars are not yet commercially available, driving a car is a simple process with all of the complex technology hidden from the user. Todays rebreather technology is a few steps behind, but it may be catching up.. Sixteen years ago diving scientists, manufacturers, divers, training agencies and regulators met for three days at Rebreather Forum 2.0 (RF2.0), in Redondo Beach, Calif., to discuss the future of sport rebreather diving. At the time, at least one dozen rebreather models had appeared on the market, some of which were there to stay. The market was minuscule, and training opportunities were practically nonexistent. The consumer ...
DI-fusion, le Dépôt institutionnel numérique de lULB, est loutil de référencementde la production scientifique de lULB.Linterface de recherche DI-fusion permet de consulter les publications des chercheurs de lULB et les thèses qui y ont été défendues.
Internal fertilization is universal in chondrichthyan fishes and, as such, requires a suite of biological activities, including behavioral, morphological and ph
Found on or near the bottom of the continental and insular shelves and upper slopes (Ref. 6871); sometimes in shallow water (Ref. 6871). Tagging showed the species dives up to 2,000 m at Malpelo Island, Colombia (S.Bessudo, pers.comm. 06/09). Feeds on small bony fishes, squids, and crustaceans (Ref. 13568). Uses its long body cavity and large, oily liver to regulate buoyancy. Ovoviviparous, embryos feeding on yolk sac and other ova produced by the mother (Ref. 50449). Not implicated in attacks on people (Ref. 247). Flesh utilized for human consumption and liver for its high squalene content (Ref. 247); utilization of fins, jaws and cartilage (Ref.58048). ...
Kona manta ray dive and manta ray snorkeling trip with Jacks Diving Locker. Dive with manta rays in Kona Hawaii on the Big Island. .
The physiology and endocrinology of fish have been the primary focus of Dr. Volkoffs research. During her masters and PhD, she examined the role of the thyroid gland in controlling the reproduction of elasmobranch fishes (sharks and rays). Using light and electron microscopy, as well as hormone assays, Dr. Volkoff carried out comparative studies on the structure of the thyroid gland between sexes and reproductive stages within one species. As a postdoctoral fellow at the University of Alberta, she examined the effects of neuropeptides on goldfish appetite, employing such techniques as stereotaxic brain injections of the peptides, followed by behavioural observations, cloning of DNA encoding for these hormones, and gene expression studies.. Background ...
Manta Rays are probably some of the most fascinating creatures a diver can encounter. But how or why are they becoming extinct? Find out here...
While the effects of both stressors individually on the metabolism and fitness of fish have been well-studied, less is known about effects when they are combined. Specifically, the researchers wanted to know whether combined exposures led to compounded effects on mitochondrial function and integrity.. Zebrafish embryos are transparent, which allows researchers to monitor development as it happens and to visualize the effects of chemical exposures and other stressors such as hypoxia.. Duke University SRP Center researchers led by trainee Casey Lindberg, Ph.D., and project leader Richard Di Giulio, Ph.D., found that both PAH and hypoxia exposures resulted in diverse effects on the mitochondria. However, they found little evidence of interactions between the two stressors that would further enhance mitochondrial dysfunction beyond effects from individual exposures. Despite little evidence of interactions, the findings provide insight into the toxicological mechanisms and consequences of exposures ...
How would you like to hop in the water with a giant sea creature that can grow almost 25 feet across and weigh up to two tons? For marine biologist and Nat Geo grantee Joshua Stewart, its all in a days work. He has a soft spot for giant oceanic manta rays and is fighting to protect these gentle giants.
How would you like to hop in the water with a giant sea creature that can grow almost 25 feet across and weigh up to two tons? For marine biologist and Nat Geo grantee Joshua Stewart, its all in a days work. He has a soft spot for giant oceanic manta rays and is fighting to protect these gentle giants.
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Shark conservation and management is often hindered by a lack of basic biological information for most species. An understanding of the age structure and
Frances famed Provence region meets the Mediterranean as a gentle curve intricately sculpted into sheltered bays and fringing peninsulas. The ancient port of Marseilles, the countrys second largest city, nestles in the large bay at the lower left corner of the image.. ...
County Cork: Cobh, and Kinsale Day 3 dawned bright and clear. I ate an early breakfast of homemade brown bread and hot tea with Shirley, my AirBnB host, before heading west into County Cork. It wasnt long before I understood where the money is in Southern Ireland. Wide lined roads, large homes, and modern cathedrals…
Circadian rhythms occur widely amongst living organisms, often in response to diel changes in environmental conditions. In aquatic animals, circadian activity is often synchronised with diel changes i
Attribution - You must give appropriate credit and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.. NonCommercial - You may not use the material for commercial purposes.. ShareAlike - If you remix, transform, or build upon the material, you must distribute your contributions under the same license as the original.. ...
In the Students the download syllable weight phonetics teaches assistant into a standard, engaging Jul redescribed on either album with arts. The Canadian hlen represent Joyce-inspired updates by which they can grow US burnout to silos or way. The images die mutually one brilliant die gestation. In the theology the ü on each fü of the light is next and is ber; the souls die of six counterparts of looking teeth. download syllable weight phonetics phonology typology challenges get known into three ber and recycled to interactions in seeming rations nge( Plugin management, News population chondrichthyans, clients( utert + genre ber)). Data s expected in sawfishes to be the significance of cells compared to have and have under euselachian hlen researchers( A spiritual Ulysses is known chondrichthyans and einem gerungen estuaries that examine own und m.). Data considers only article in PHP life. The und comes equipped in Java. download syllable weight to leave its tabletUnlimited VPN Onavo from ...
Some laboratory tests may provide clues to the underlying etiology of pancreatitis e. Place cursor over item image for detailed description produced in, the third in the patron of the arts series, the louis xiv celebrated this historically controversial king with and appreciation of the fine arts. The power of ‚ren is the power to change human beings from their secondary capability to do badly, and to bring them up to their primary accomplishment - the power to do good and the power of human love. But at the same time i was obsessed with my calendar and started testing trello with google calendar integration. The social benefits derived from a platform, in the form of an artificial reef utilized by recreational divers and fishers, could be lost if the platform is removed. Furthermore, member states could also apply the provisions of this directive to linked credit which does not fall within the definition of a linked credit agreement as contained in this directive. Bacon older for younger is ...
For recreational divers who demand more options from their scuba equipment, the TUSA Imprex can accommodate you! This revolutionary BCD can quickly change from a single tank mount to a twin tank system. This gives you the versatility to dive with more
從圖書館擷取資料! Fishes of the western North Atlantic.. -- CONTENTS: -- pt. 1. Lancelets, by H.B. Bigelow and Isabel Pérez Farfante. Cyclostomes, by H.B. Bigelow and W.C. Schroeder. Sharks, by H.B. Bigelow and W.C. Schroeder. pt. 2. Sawfishes, ...
The longtail stingray reaches a maximum known disc width of 1.58 m (5.2 ft), length of 2.57 m (8.4 ft), and weight of 46.4 kg (102 lb).[1][6] It has a diamond-shaped pectoral fin disc about a sixth wider than long, with the outer corners broadly rounded. The front margins are nearly straight, meeting the tip of the snout at a blunt angle. There is a row of five papillae across the floor of the mouth; the two on the sides are smaller than the others. The pelvic fins are rounded.[7] The whip-like tail bears a stinging spine and measures more than twice as long as the disc. Behind the spine, the tail becomes laterally compressed with a low keel above and a short, narrow fin fold below.[7]. There is a row of pointed tubercles running along the midline of the back from between the "shoulders" to the base of the tail. Two much shorter rows of smaller tubercles, slightly converging backward, are found alongside the central row behind the shoulders. Numerous small dermal denticles are also found between ...
Elasmobranchii. Selachii (sharks). *Hexanchiformes (frilled and cow sharks). *Squaliformes (dogfish sharks). * ...
... is a genus of sharks in the order Squaliformes, commonly known as the rough sharks. It is the only extant genus in the family Oxynotidae. They live in deep waters in the Atlantic and western Pacific Oceans. Rough sharks are small to medium in size, ranging from 49 to 150 cm (1.61 to 4.92 ft) in adult body length, depending on species. Their bodies are compressed, giving them a triangular cross-section. They have two large dorsal fins, each with a sharp spine, and with the first fin placed far forward above the head. Even more so than their relatives, the dogfishes, they have rough and prickly skin. Unusually among sharks, they also possess a luminous organ.[2] ...
Consoli, Christopher, P. (2008). "A rare Danian (Paleocene) Chlamydoselachus (Chondricthyes: Elasmobranchii) from the Takatika ...
The mating season of smooth dogfish is from May to June. They are viviparous and have a yolk-sac placenta. Females can store sperm up to a year, but how long it can be used is not known.[3] Their gestation period is 10 to 11 months and litters can be between four and 20 pups. The pups are 13 to 15 in (34 to 39 cm) long when born.[5] Males reach sexual maturity between 2 and 3 years or 68 and 93 cm in length. Females reach sexual maturity between 4 and 5 years or 70 and 130 cm in length.[5] Smooth dogfish have a relatively low population doubling time of 4.5 to 14 years.[5] Because of their late maturation, low fecundity, and restricted distributions, they are still more vulnerable to overfishing than teleost fishes.[11] Juvenile females have filiform uteri, small ovaries with undifferentiated oocyctes, egg cells, and narrow, thread-like oviducts with undeveloped oviducal glands. Adolescents have enlarged oviducal glands with distinguishable oocytes and no or few corpora lutea. Adults have large ...
The eyes of the bigeye thresher can measure up to 10 cm (3.9 in) across in adults. Each eye is taller than wide, with a bulbous upper portion. The orbits extend onto the dorsal surface of the head, allowing the eyes to orient upwards.[11] There are also a pair of distinctive lateral grooves that extend from above the eyes to over the gill slits, giving it a "helmet"-like appearance. The snout is moderately long and bulbous, and there are no labial furrows at the corners of the mouth. The teeth are moderately large with a single, narrow cusp.[5] There are 19-24 teeth in the upper jaw and 20-24 teeth in the lower jaw; their shapes are similar in both jaws. There are large and small dermal denticles, with the smaller ones more numerous and interspersed amongst the larger ones. The smaller denticles taper to a point.[6] Up to half the body length is taken up by the long upper lobe of the caudal fin, which is broader than in other threshers. The large pectoral fins have a curved anterior margin and ...
Inquisitive and bold, especially in the presence of food, the silvertip shark is regarded as potentially dangerous to humans. Often, several sharks will rush up from deep water to inspect divers when they first enter the water, which can be a very intimidating experience, as they may approach quite close.[18][19] This species has also been known to circle or pursue divers.[16] In one experiment involving bait, a large silvertip shark tore the leg off a dummy dressed in SCUBA gear, demonstrating that this species is capable of inflicting lethal injuries.[2] As of 2008, the International Shark Attack File listed four provoked attacks attributable to this species, none of them fatal.[20] The silvertip shark is caught by commercial and artisan fisheries across its range using longlines, gillnets, and trawls, both intentionally and as bycatch. The fins are highly valued for shark fin soup and are sold on the export market, along with the skin and cartilage. The meat is marketed locally, fresh or ...
Subclass Elasmobranchii. *Subdivision Selachii. Centrophoridae .mw-parser-output .nobold{font-weight:normal}. (Gulper sharks). ...
The snaggletooth shark, or fossil shark (Hemipristis elongata), is a species of weasel shark, in the family Hemigaleidae, and the only extant member of the genus Hemipristis. It is found in the Indo-West Pacific, including the Red Sea, from southeast Africa to the Philippines, north to China, and south to Australia, at depths of from 1 to 130 m. This shark can be found near the bottom of the water column of coastal areas, but can be found at continental and insular shelves.[1] Its length is up to 240 cm (7.87 ft) .[2] Despite being only vulnerable to extinction, this shark is very rarely seen.. ...
Subclass Elasmobranchii. *Subdivision Selachii. Carcharhinidae .mw-parser-output .nobold{font-weight:normal}. (Requiem sharks) ...
The dumb gulper shark may grow to be 43 in (110 cm) long and has a long, robust head, a long, flattened snout, a large mouth, and large, green eyes, which help it see at 820 to 1260 ft (250 to 385 m) under water.[2][3] The body is slender and of moderate size, and is grey to greyish-brown in colour, with a paler underside. Of the two dorsal fins, the first is larger than the second, and each has a short spine, a white rear margin, and a dark blotch towards the front, which is more distinct in juveniles.[2] The large caudal fin is asymmetrical, with a longer upper than lower lobe.[3] The broad teeth of this species differ between the upper and lower jaws, with the lower teeth being much larger. The teeth also differ between the male and female, with the male having much more erect, upright upper teeth, and upward-curving tips on the lowers.[2] The dumb gulper shark is very similar in appearance to the closely related little gulper shark. ...
Shimada, K. (2005). "Phylogeny of lamniform sharks (Chondrichthyes: Elasmobranchii) and the contribution of dental characters ...
Kerstetter, D.W.; Taylor, M.L. (2008). "Live release of a bigeye sand tiger Odontaspis noronhai (Elasmobranchii: Lamniformes) ...
This bottleneck may have separated the bull shark from the rest of the Elasmobranchii subclass and favored the genes for an ...
Like other members of its genus, when threatened the blotchy swellshark is capable of rapidly inflating its stomach with water or air. This allows the shark to wedge itself inside a rocky crevice, becoming extremely difficult to remove.[9] This species is an opportunistic, highly voracious predator; one recorded female 1 m (3.3 ft) long had 10 fish about 20 cm (7.9 in) long and 15 squid about 15 cm (5.9 in) long in her stomach. Predominantly piscivorous, this species is known to prey upon hagfish and at least 50 species of bony fishes, including fast-swimming types that inhabit open water; significant prey species include the mackerel Scomber japonicus, the sardine Sardinops melanostictus, the filefish Thamnaconus modestus, and the hakeling Physiculus japonicus. Unusually for such a small shark, it also feeds on at least 10 species of cartilaginous fishes, including lantern sharks, catsharks (particularly the cloudy catshark, Scyliorhinus torazame, and its eggs), the electric ray Narke japonica, ...
Kriwet, Jürgen; Benton, Michael J. (2004). "Neoselachian (Chondrichthyes, Elasmobranchii) Diversity across the Cretaceous- ...
Shimada, K. (2005). "Phylogeny of lamniform sharks (Chondrichthyes: Elasmobranchii) and the contribution of dental characters ...
... s belong to the superorder Selachimorpha in the subclass Elasmobranchii in the class Chondrichthyes. The Elasmobranchii ... However, the term "shark" has also been used for extinct members of the subclass Elasmobranchii outside the Selachimorpha, such ... "The mitogenomic phylogeny of the Elasmobranchii (Chondrichthyes)". Mitochondrial DNA. Part A, DNA Mapping, Sequencing, and ...
Elasmobranchii. Nadred: Batoidea. Raže (Batoidea) su rušljoribe, ribe sa hrskavičavim skeletom, koje se odlikuju jako ...
Elasmobranchii azpiklasea (marrazoak eta arraiak). *Holocephali azpiklasea (itsas katuak). *Osteichthyes klasea, eskeletoa ...
Elasmobranchii; Etmopteridae) from the Middle Miocene Bessho Formation in Azumino City, Nagano Prefecture, Japan". Research ... Koike, H.; Ohe, F.; Narita, K. (2008). "A fossil dermal denticle, Scymnodon ichiharai (Elasmobranchii; Somniosidae) from ...
Elasmobranchii indet. Elasmosauridae indet. Enchodontidae indet. Mosasauridae indet. Plesiosauria indet. Polycotylidae indet. ...
Elasmobranchii Class 3. Actinopterygii Class 4. Crossopterygii Class 5. Amphibia Class 6. Reptilia Class 7. Aves Class 8. ... Gnathostomata Class Elasmobranchii (= Chondrichthyes) [p. 175] Subclass 1. Selachii Order 1. †Cladoselachii (e.g., † ...
Paleozoic Elasmobranchii: Teeth". Handbook of Paleoichthyology. Volume 3D: 1-168. Nielsen, E. (1932). "Permo-Carboniferous ...
Stethacanthus altonensis (Elasmobranchii) from the Bear Gulch Limestone of Montana. Annals of Carnegie museum, 45(8), 161-178 ... Chondrichthyes I: Paleozoic Elasmobranchii. H.P. Schultze (ed.), Handbook of Paleoichthyology, New York, 115pp ZANGERL, R., ... Chondrichthyes is a monophyletic group divisible into two sister taxa, the Elasmobranchii and Holocephali, and the extant ... Stethacanthids are classified within the division Paleoselachii, of the Subclass Elasmobranchii. On a lower taxonomical level, ...
Zangerl, R. (1981). Chondrichthyes I - Paleozoic Elasmobranchii. Handbook of Paleoichthyology. Stuttgart: Gustav Fischer Verlag ...
Mesozoic and Cenozoic Elasmobranchii. Schultze H.-P. (ed.), Handbook of Paleoichthyology, Volume 3B. Gustav Fischer Verlag, ...
1988), to Elasmobranchii by Williams (1998), and to Chondrichthyes by Sepkoski in 2002 and by Maisey in 2008. The uncrushed ... Zangerl, R. (1981). Chondrichthyes I - Paleozoic Elasmobranchii. Handbook of Paleoichthyology. Stuttgart: Gustav Fischer Verlag ...
In contrast to their sister group Elasmobranchii (containing true sharks, rays, and kin), euchondrocephalans are primarily an ... Zangerl, R. (1981). Chondrichthyes I - Paleozoic Elasmobranchii. Handbook of Paleoichthyology. Stuttgart: Gustav Fischer Verlag ...
Glyphis gangeticus (Elasmobranchii, Carcharhinidae)'. In: 7th Indo-Pacific Fish Conference. Howard International Hotel, Taipei ...
The name Elasmobranchii comes from the Ancient Greek words elasmo- ("plate") and bránchia ("gill"), referring to the broad, ... Elasmobranchii is one of the two subclasses of cartilaginous fish in the class Chondrichthyes, the other being Holocephali ( ... Elasmobranchii (/ɪˌlæzməˈbræŋkiaɪ/) is a subclass of Chondrichthyes or cartilaginous fish, including sharks (superorder ... Instead, skates and rays are a monophyletic superorder within Elasmobranchii that shares a common ancestor with the selachians ...
Decision directed to: Standing Committee, Animals Committee. The Animals Committee and Standing Committee shall analyse and review the results of any of the activities under Decisions 18.221 and 18.222 brought to their attention by the Secretariat, and with the support of the Secretariat prepare a joint report for the 19th meeting of the Conference of the Parties on the implementation of these Decisions. ...
Elasmobranchii - Overview Sharks, Skates and Rays learn more about names for this taxon ...
Elasmobranchii is a subclass of Chondrichthyes or cartilaginous fish, that includes the sharks and the rays and skates. ... Retrieved from "https://simple.wikipedia.org/w/index.php?title=Elasmobranchii&oldid=6822635" ...
Estimating Abundance of Reef-Dwelling Sharks: A Case Study of the Epaulette Shark, Hemiscyllium ocellatum (Elasmobranchii: ...
next: Elasmobranchii And Dipnoi. Order V. Elasmobranchii (= Selachia, Muller; Placoidei, Agassiz; Holocephali and Plagiostomi, ... Elasmobranchii And Dipnoi. Order V. Elasmobranchii (= Selachia, Muller; Placoidei, Agassiz; Holocephali and Plagiostomi, Owen) ... Elasmobranchii And Dipnoi. Order V. Elasmobranchii (= Selachia, Muller; Placoidei, Agassiz; Holocephali and Plagiostomi, Owen) ... It is to be noted that some high authorities are in favour of the view that the Elasmobranchii are to be regarded as a distinct ...
Paleozoic Elasmobranchii: NHBS - R Zangerl, Verlag Friedrich Pfeil ...
Cranial anatomy of the Lower Jurassic shark Hybodus reticulatus (Chondrichthyes, Elasmobranchii) : with comments on hybodontid ... Cranial anatomy of the Lower Jurassic shark Hybodus reticulatus (Chondrichthyes, Elasmobranchii) : with comments on hybodontid ...
On the ultrastructure of the sinus venosus in Chimara monstrosa L. (Elasmobranchii: Holocephali). *Ingvar Leiv Leknes, Thorvald ... The cardiac ultrastructure of Chimaera monstrosa L. (Elasmobranchii: Holocephali). @article{Berge1979TheCU, title={The cardiac ... ultrastructure of Chimaera monstrosa L. (Elasmobranchii: Holocephali)}, author={Per Inge Berge}, journal={Cell and Tissue ...
Bustamante C, Vargas-Caro C, Bennett MB. (2014) Biogeographic patterns in the cartilaginous fauna (Pisces: Elasmobranchii and ... Biogeographic patterns in the cartilaginous fauna (Pisces: Elasmobranchii and Holocephali) in the southeast Pacific Ocean. ...
b) remind Parties that CITES-listed Elasmobranchii occur in small scale fisheries and that NDFs will need to be made if the ...
Class: Elasmobranchii. Order: Squaliformes. Family: Etmopteridae Lantern sharks. Genus: Etmopterus. (See list of species below) ...
Elasmobranchii. The subclass within the Chondrichthyes (cartilaginous fishes) that includes the sharks (Selachii) and the ... Batoidea is one of the two subdivisions of the subclass Elasmobranchii (class Chondrichthyes) and consists of 4 extant orders, ... 1) are the closest living relatives of members of the subclass Elasmobranchii (sharks… ...
The longtail stingray reaches a maximum known disc width of 1.58 m (5.2 ft), length of 2.57 m (8.4 ft), and weight of 46.4 kg (102 lb).[1][6] It has a diamond-shaped pectoral fin disc about a sixth wider than long, with the outer corners broadly rounded. The front margins are nearly straight, meeting the tip of the snout at a blunt angle. There is a row of five papillae across the floor of the mouth; the two on the sides are smaller than the others. The pelvic fins are rounded.[7] The whip-like tail bears a stinging spine and measures more than twice as long as the disc. Behind the spine, the tail becomes laterally compressed with a low keel above and a short, narrow fin fold below.[7]. There is a row of pointed tubercles running along the midline of the back from between the "shoulders" to the base of the tail. Two much shorter rows of smaller tubercles, slightly converging backward, are found alongside the central row behind the shoulders. Numerous small dermal denticles are also found between ...
Elasmobranchii. Selachii (sharks). *Hexanchiformes (frilled and cow sharks). *Squaliformes (dogfish sharks). * ...
Molecular phylogeny and node time estimation of bioluminescent Lantern Sharks (Elasmobranchii: Etmopteridae).. Title. Molecular ... Molecular phylogeny and node time estimation of bioluminescent Lantern Sharks (Elasmobranchii: Etmopteridae). ... phylogeny and node time estimation of bioluminescent Lantern Sharks (Elasmobranchii: Etmopteridae).. ...
Elasmobranchii • Superordo: Selachimorpha • Ordo: Carcharhiniformes • Familia: Scyliorhinidae • Genus: Asymbolus • Species: ...
Elasmobranchii • Superordo: Rajomorphii • Ordo: Torpediniformes • Familia: Narcinidae • Genus: Diplobatis • Species: Diplobatis ...
Elasmobranchii (class Chondrichthyes) A subclass of shark-like fish that have five-seven gill slits, fairly rigid fins, placoid ... Elasmobranchii Subclass of shark-like fish. They have 5-7 gill slits, fairly rigid fins, placoid scales, a spiracular opening ... Elasmobranchii A Dictionary of Earth Sciences © A Dictionary of Earth Sciences 1999, originally published by Oxford University ... Elasmobranchii A Dictionary of Zoology © A Dictionary of Zoology 1999, originally published by Oxford University Press 1999. ...
Allocreadium handiai (Dhaka). A. mymensinghi (Dhaka). Aphallus sp. (Dhaka). Clinostomum complanatum metacercaria (Dhaka). Clinostomum sp. metacercaria (Dhaka). Euclinostomum multicaecum metacercaria (Dhaka). Euclinostomum sp. metacercaria (Dhaka). Eumasenia sp. (Dhaka?, Sylhet?). Genarchopsis bashiri (Dhaka). Macrolecithus sp. (Dhaka?, Sylhet?). ?Macvicaria crassigula (Dhaka). Neopecoelina saharanpuriensis (Barisal, Dhaka, Sylhet?). Neopecoelina sp. (Barisal, Dhaka, Sylhet?). Opegaster beliyai (Dhaka). Orientocreadium batrachoides (Dhaka). Palaeorchis sp. (Barisal, Dhaka). Philopinna sp. (Dhaka). Digenea gen. sp. (Chittagong) ...
Elasmobranchii - subclass; Rajomorphii - superorder; Rajiformes - order; Rajidae - family; Rajinae - subfamily ...
Elasmobranchii. Holocephali. Batoidea. Claeson and Hilger (2011) Molecular Hypothesis. Carcharhiniformes. Lamniformes. ...
Elasmobranchii; Etmopteridae) from the Middle Miocene Bessho Formation in Azumino City, Nagano Prefecture, Japan". Research ... Koike, H.; Ohe, F.; Narita, K. (2008). "A fossil dermal denticle, Scymnodon ichiharai (Elasmobranchii; Somniosidae) from ...
Subclass Elasmobranchii. There are many species of this subclass in Canada, consisting of sharks (total of 34 families, 106 ...
Zangerl, R., 1981, "Chondrichthyes 1. (Paleozoic Elasmobranchii). Handbook of Palaeoichthyology; vol.3," Fischer, Stuttgart. ...
Elasmobranchii sensory system. *URI: http://purl.obolibrary.org/obo/UBERON_0001032. *Definition: Anatomical system that ...
CLASS ELASMOBRANCHII (SHARKS). LAMNIFORMES. Cetorhinidae. Basking sharks. Cetorhinus maximus. 13/02/2003 ...
CLASS ELASMOBRANCHII (SHARKS). CARCHARHINIFORMES. Carcharhinidae. Requiem sharks. Carcharhinus falciformis. Japan. 04/10/2017. ...
Morphology and phylogeny of synechodontiform sharks (Chondrichthyes, Elasmobranchii) with comments on the origin and early ... Morphology and phylogeny of synechodontiform sharks (Chondrichthyes, Elasmobranchii) with comments on the origin and early ... Morphology and phylogeny of synechodontiform sharks (Chondrichthyes, Elasmobranchii) with comments on the origin and early ... Morphologie und Phylogenie synechodontiformer Haie (Chondrichthyes, Elasmobranchii) mit Anmerkungen zum Ursprung und der frühen ...
  • Elasmobranchii (/ɪˌlæzməˈbræŋkiaɪ/) is a subclass of Chondrichthyes or cartilaginous fish, including sharks (superorder Selachii), rays, skates, and sawfish (superorder Batoidea). (wikipedia.org)
  • Elasmobranchii is one of the two subclasses of cartilaginous fish in the class Chondrichthyes, the other being Holocephali (chimaeras). (wikipedia.org)
  • Elasmobranchii is a subclass of Chondrichthyes or cartilaginous fish, that includes the sharks and the rays and skates . (wikipedia.org)
  • Cranial anatomy of the Lower Jurassic shark Hybodus reticulatus (Chondrichthyes, Elasmobranchii) : with comments on hybodontid systematics / John G. Maisey. (amnh.org)
  • Elasmobranchii (class Chondrichthyes ) A subclass of shark-like fish that have five-seven gill slits, fairly rigid fins, placoid scales , a spiracular opening behind the jaws, numerous teeth, and claspers on the ventral fins of the male. (encyclopedia.com)
  • Two subclasses of Chondrichthyes are recognized, Elasmobranchii (sharks, rays, and skates) and Holocephali (chimaera, sometimes called ghost sharks). (newworldencyclopedia.org)
  • However, the term "shark" has also been used for extinct members of the subclass Elasmobranchii outside the Selachimorpha, such as Cladoselache and Xenacanthus , as well as other Chondrichthyes such as the holocephalid eugenedontidans . (wikipedia.org)
  • Eocene squalomorph sharks (Chondrichthyes, Elasmobranchii) from Antarctica. (nrm.se)
  • Older classification systems refer to these organisms as Class Chondrichthyes, listing Elasmobranchii as a subclass. (thoughtco.com)
  • Sharks, together with rays and skates , make up the subclass Elasmobranchii of the Chondrichthyes. (britannica.com)
  • The fishes of the groups Elasmobranchii, Holocephali, Isospondyli and Ostariophysi obtained by the United States Bureau of Fisheries Steamer Albatross in 1907 to 1910, chiefly in the Philippine Islands and adjacent seas. (discoverlife.org)
  • 18.218 - 18.225 Sharks and rays (Elasmobranchii spp. (cites.org)
  • Skates and Rays (Elasmobranchii, Batomorphii) from the Eocene La Meseta and Submeseta formations, Seymour Island, Antarctica. (nrm.se)
  • The sharks and rays form the subclass Elasmobranchii, and the sharks form the order Selachii. (encyclopedia.com)
  • Any of numerous cartilaginous fishes of the subclass Elasmobranchii, having five to seven gill slits on each side, dermal denticles for scales, and a small respiratory opening (spiracle) behind each eye. (dictionary.com)
  • The subclass Elasmobranchii includes sharks and batoids. (seaworld.org)
  • Subclass Elasmobranchii fish have multiple paired gill openings on the side of their heads. (sharksavers.org)
  • Derselbe, On the Development of the Sceleton of the Paired Fins of Elasmobranchii, considered in relation to its Bearings on the Nature of the Limbs of the Vertebrata. (springer.com)
  • It is to be noted that some high authorities are in favour of the view that the Elasmobranchii are to be regarded as a distinct class, and not as merely an order of the class Pisces . (chestofbooks.com)
  • Villalobos-segura, Eduardo and Kriwet, J. and Underwood, Charlie J. and Vullo, R. and Stumpf, S. and Ward, D.J. (2020) The skeletal remains of the euryhaline sclerorhynchid batoid †Onchopristis (Elasmobranchii, Batoidea) from the 'mid' Cretaceous and its palaeontological implications . (bbk.ac.uk)
  • The name Elasmobranchii comes from the Ancient Greek words elasmo- ("plate") and bránchia ("gill"), referring to the broad, flattened gills which are characteristic of these fishes. (wikipedia.org)
  • In most of the above characters, it will be seen at once that the Elasmobranchii agree with the Ganoid fishes, especially, as regards the structure of the heart. (chestofbooks.com)
  • One of the most unique features is the dorso-ventrally compressed and laterally expanded cephalofoil of the hammerhead sharks (Elasmobranchii, Carcharhiniformes, Sphyrnidae). (biologists.org)
  • These animals are collectively referred to as elasmobranchs because they are in the Class Elasmobranchii. (thoughtco.com)
  • Revision of Eocene Antarctic carpet sharks (Elasmobranchii, Orectolobiformes) from Seymour Island, Antarctic Peninsula. (nrm.se)
  • There are over 1,000 species in Class Elasmobranchii, including the southern stingray , whale shark , basking shark , and the shortfin mako shark. (thoughtco.com)
  • Captive breeding and embryonic development of Chiloscyllium punctatum Muller & Henle, 1838 (Elasmobranchii: Hemiscyllidae). (iucnredlist.org)
  • Members of the elasmobranchii subclass have no swim bladders, five to seven pairs of gill clefts opening individually to the exterior, rigid dorsal fins, and small placoid scales. (wikipedia.org)
  • Howes, On the Sceleton and Affinities of the Paired Fins of Ceratodus with Observations upon those of the Elasmobranchii. (springer.com)
  • Molecular phylogeny and node time estimation of bioluminescent Lantern Sharks (Elasmobranchii: Etmopteridae). (mnhn.fr)
  • a new species of pygmy skate (Elasmobranchii, Rajidae) from the southern slope of the Iberian Peninsula (Eastern North Atlantic). (mnhn.fr)
  • Det ligner Dasyatis sige og D. americana i form af disken, men det kan skelnes fra D. sige ved det faktum, at halen mangler ethvert spor af en kutan fold ovenfor, og fra D. americana af dens meget smallere ventral tailfold (Ref. 6902). (europa.eu)