Checklist of chondrichthyans in indian waters core. Chondrichthyan definition is a fish of the class chondrichthyes. The electronic version of this article in portable document format pdf. Bodies completely covered with bony armor plates 4. Superclass gnathostomata jawed fishes chondrichthian. The skin is tough, possesses minute placoid scales and mucous glands. First appearing on earth almost 450 million years ago, cartilaginous fish today include both fearsome predators and harmless mollusceaters. Rajoidei article pdf available in environmental biology of fishes 802. It aids conservation and education by housing many animals that are threatened or endangered. Worlds best powerpoint templates crystalgraphics offers more powerpoint templates than anyone else in the world, with over 4 million to choose from.
Members of the chondrichthyes chondrichthyans, or the cartilaginous fishes are. Chondrichthyes and osteichthyes questions and study guide. Learn vocabulary, terms, and more with flashcards, games, and other study tools. The class chondrichthyes includes sharks, skates, rays, and chimaeras. An introduction to the classification of elasmobranchs core. The chondrichthyes comprising the sharks, rays and chimaeras are characterised by a skeleton that is entirely cartilaginous, but more or. Chondrichthyans, checklist, taxonomy, status, india, diversity, management.
Scallops of the placoid type, exclusive of this group are scales similar to small teeth, formed by dentin and a type of enamel enamel is a highly mineralized tissue, very hard, of epidermal origin, as opposed to dentin and bone, of origin mesodermic, immersed in the body of the animal the tip of the scale breaks the skin, giving a rough, sandpaper texture. General characteristics of chondrichthyescartilaginous skeletonsplacoid scales 2 chambered hearts. Theyll give your presentations a professional, memorable appearance the kind of sophisticated look that todays audiences expect. Chondrichthyes article about chondrichthyes by the free. Sharks, skates, and rays make up chondrichthyes, or cartilaginous fish. The elasmobranchs are fishlike vertebrates that differ from bony fishes in many respects. Alrightly, i need lots and lots of facts and description about the habitat of chondrichthyes with some example. Difference between chondrichthyes and osteichthyes zoology. On the application of the laws of evolution to the arrangement of the vertebrata, and more particularly of the mammalia. Download the flyerget adobe acrobat reader pdf icon. Elasmobranchii sharks, rays and skates and holocephali chimaera, sometimes called ghost sharks.
Resemble bony fish and terrestrial vertebrates in having jaws, paired appendages, visceral arches located deeply next to the pharynx, an inner ear with three semicircular canals, and paired nasal cavities. Chondrichthyes characteristics include a cartilaginous skeleton, lack of a swim bladder, lipid storage restricted to. They bring water into their bodies using one of two methods. Download fulltext pdf biodiversity and systematics of skates chondrichthyes. Chondrichthyan, class chondrichthyes, also called chondrichthian, any member of the diverse group of cartilaginous fishes that includes the sharks, skates, rays, and chimaeras. With the holocephali now represented by only 40 living species of chimaera in the single order. The class chondrichthyes comprises almost 1050 extant species ofcartilaginous fishes, encompassing skates, sharks, rays, andchimaeras. Itis taxonomy is based on the latest scientific consensus available, and is provided as a general reference source for interested parties. Respiration by means of 5 to 7 pairs of gills with separate and exposed gill slits, no operculum.
The term elasmobranchs or chondrichthyans refers to the group of marine. Notochord supports body nervous system develops from dorsal nerve cord embryos have pharynx with slits embryos have tail that extends past anus. The chondrichthyes generally exhibit kselected life history strategies slow growth, late maturity, low fecundity and productivity, long life, and gestation periods, especially when compared. Members of chondrichthyes all lack true bone and have a skeleton made of cartilage the flexible material you can feel in your nose and ears. These odd fish appear to be chimeroid in that they have characteristics of sharks and bony fishes also, many have a ratlike tail. They are cartilaginous fish along with skates, rays and chimeras.
The upcoming discussion will update you about the differences between chondrichthyes and osteichthyes. The class contains 12 orders which are divided between 2 monophyletic subclasses, the elasmobranchii sharks, rays and skates and holocephali chimaeras. Members of chondrichthyes all lack true bone and have a skeleton made of cartilage the flexible material you can. Chondrichthyes also lack ribs, so if they leave water, a larger species own body weight would crush their internal organs a long time before they would even suffocate. Actually, the skeleton of chondrichthyans is calcified or in. In this article we will discuss about the classification of class chondrichthyes. Chondrichthyes is a class that contains the cartilaginous fishes. Other characteristics of the chondrichthyes include placoid scales, clasper organs on the pelvic fins of males for internal fertilization, a urearetention mechanism, and the absence of an air swim bladder. Cartilaginous fishes superclass gnathostomata jawed fishes class placodermi plateskinned extinct class acanthodii spiny sharks extinct class chondrichthyes living class sarcopterygii living. Scientists examine fins, rays and spines, scales, mouths, body shape, relative size and shape of body parts, and the. Chondrichthyes accessscience from mcgrawhill education.
While every effort has been made to provide the most reliable and uptodate information available, ultimate legal requirements with respect to species are contained in. Having dark backs help to disguise fishes from both predators and prey that are above them, this is because their dark backs help to blend in with the darker bottom of the sea floor. Ppt chondrichthyes powerpoint presentation free to. For all the lovely men or women out their who prefer cartilage over bone. Pdf on nov 1, 2016, antonis petrou and others published agnatha, chondrichthyes and osteichthyes find, read. General characteristics runs along the dorsal surface from head to tail and forms the main skeletal axis of the body, surrounds and more or less replaces the notochord as the chief stiffener of the body in locomotion. The body is covered with minute and microscopic placoid scales, the skin is tough.
The euchondrocephalian clade 1 the euchondrocephali a name from 3 greek roots that mean true cartilaginous heads are commonly called chimeras, named for a monster of greek mythology that had the head of a lion, the body of a goat, and the tail of a dragon. Similarities and differences between chondrichthyes and. Chondrichthyans article about chondrichthyans by the. Seen in chondrichthyes and ancestral sarcopterygii. Kingdom animalia phillip chordata class chondrichthyes order lamniformes family lamnidae genus carcharodon species shark common name. Ram ventilation requires forward movement by the organism. However, it is not a legal authority for statutory or regulatory purposes. Pdf ecology and life history characteristics of chondrichthyan fish. Chondrichthyes characteristics include a cartilaginous skeleton, lack of a swim bladder, lipid storage restricted to the liver. Dichotomous keychondrichthyes wikibooks, open books for. The class name chondrichthyes cartilaginous fish refers to the cartilaginous skeleton of these organisms.
There are five to seven fully developed gill clefts, opening separately to the exterior. Chondrichthyes and osteichthyes reptiles and birds mammals great white shark chondrichthyes classification. The dallas world aquarium and zoo is located in the west end historic district. Characteristics of earliestcharacteristics of vertebrates craniates 1. Chondrichthyes characteristics include a cartilaginous skeleton, lack of a swim bladder, lipid storage restricted to the liver, unique hematopoietic organs, and bacteremia in clinically normal individuals. Camouflage in chondrichthyes a coloration seen in cartilaginous fish such as sharks, skates and rays is countershading. The skeleton is composed of cartilage and, although often calcified especially in the vertebrae, lacks true bone except in the roots of teeth. Only their teeth, and sometimes their vertebrae, are calcified. Like other fish skeletons youve seen, youd expect a rib cage and hard bones to reveal themselves as the animal decayed. One of the primary characteristics present in most sharks is the heterocercal tail, which. The appearance of external physical characteristics is one factor scientists consider in classifying fish. Holocephali chimaeras chimaeras are sometimes called ghost fish, ratfish or rabbit fish.
Pdf agnatha, chondrichthyes and osteichthyes researchgate. Chondrichthyes or cartilaginous fishes are jawed fish with paired fins, paired nostrils, scales, twochambered hearts, and skeletons made of cartilage rather than bone. Generate extra heat by a strip of red muscle that runs along center core of the body. The class is one of the two great groups of living fishes, the other being the osteichthians, or bony fishes. Winner of the standing ovation award for best powerpoint templates from presentations magazine. From wikibooks, open books for an open world download as pdf. The chondrichthyes or cartilaginous fishes are jawed fish with paired fins, paired nostrils, scales, twochambered hearts, and skeletons made of cartilage.
They collect water in the mouths which is then passed through the gills. The name selachii is also sometimes used for the group. Subclass holocephali chimaera ciri karakteristik chondrichthyes rangka dari tulang rawan sisik berupa denticula, tipe placoid mempunyai sepasang lubang hidung. Systematics and biodiversity of sharks, rays, and chimaeras chondrichthyes of taiwan. Ecology and life history characteristics of chondrichthyan. Chondrichthyestraits and characteristics questions and. Garner, in pathology of wildlife and zoo animals, 2018. Lecture 8 class chondrichthyes cartilaginous fishes characteristics cartilaginous skeleton o faster o evade predators better o better predators themselves placoid scales teeth in replacement families o the replacement teeth are behind the functional teeth, they are needed when the current functional teeth are lost series of gill openings spiracle evolved when the hyoid arch moved to support.
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