Fish Classification PDF

Fish classification Fish classification:-  It is important to have a simple clue about the classification of some important cultured fish species for:-  Easily identification of different types of fish species.  Diagnosis of fish diseases.  Fish could be categorized into different major gro...

Fish classification Fish classification:-  It is important to have a simple clue about the classification of some important cultured fish species for:-  Easily identification of different types of fish species.  Diagnosis of fish diseases.  Fish could be categorized into different major groups according to different classifications as follow.  1-According to skeleton structure:- A- B- C- Classosteichthyes( Classchondricht Classagnatha(c bony fish hyes(cartilaginous yclostomata) orteleosts):- fish):- a) Class osteichthyes(bony fish or teleosts):- This fish in this class are characterized by:-  Bony vertebrae The fertilization is usually  Gill arches external “oviparous”  Laying large number of eggs  Presence of jaw with small size. Paired nostrils E.G. Catfish , tilapia, salmon. b) Class chondrichthyes (cartilaginous fish):- It characterized by:-  Cartilaginous The fertilization is mostly internal vertebrae “ovoviviparous or viviparous”  Gill arches  Has small number of eggs with large  Presence of jaw size E.G. Shark , rays.  Paired nostrils. cartilaginous fish:- shark rays c) Class agnatha (cyclostomata) such as lamprey and hag fish:-  The fish in this class represent the most primitive of living vertebrates and it characterized by:-  Cartilaginous vertebrae  Reproduce in freshwater riverbeds  Absence of jaw  Single median nostrils  Hatchlings go through four years  Absence of gill arches before becoming adults.  Feeding by parasitizing other fish species using their sucker, jaw-less mouth and its toothed tongue to rasp a hole in the skin of its prey for sucking the its blood. sea lamprey Mouth of a sea lamprey 2) According to the family:- 1) Family cichlidae:-  This group of fish characterized by:- a) Completely covered with scales including the body and head. b) Presence of paired lateral line. c) The structure of dorsal and anal fins is spinney rays and soft rays. d) It divided into three genera according to the type of breeding.  According to type of breeder A-mouth breeder B-subsratebreeder Genusoreochro Genussarotherd Genus tilapia mis on a) Mouth breeder:- 1) Genus Oreochromis:- O.niloticus O. aureus O. mossambicus  Nile tilapia (oreochromis niloticus) ‫البلطي النیلي‬  Nile tilapias are brownish or grayish.  Often with indistinct banding on their body, and the tail is vertically striped.  When breeding, males become reddish, especially on their fins.  Oreochromis aureus (the blue tilapia ) ‫البلطي االزرق‬  It is commonly confused with nile tilapia (oreochromis niloticus)  This species lacks the striped tail pattern.  Males are bluish overall when breeding.  Oreochromis mossambicus ‫البلطي الموزمبیقي‬ Native coloration is a dull greenish or yellowish, and weak banding may be seen. 2) Genus sarotherodon:- Sarotherodon galillaeus ‫مشط ابیض‬ To differentiate from other species (tilapia zelli) it‘s larger than and white.  Mouth-brooders pick up their fertilized eggs and hold them in the mouth until the young are large enough to venture out into the world.  Some species will take their babies back into the mouth in times of danger, while others ignore them once they have been released.  The big advantage:-  Their eggs are relatively safe in the adult's mouth and most will at least reach the free- swimming stage.  The downside is that:-  Fewer eggs are produced in each spawning  Most adults stop feeding while brooding their eggs.  They need longer to recover between spawnings than many of their substrate-spawning cousins. b) Substrate breeder:- include genus tilapia :- T.zellii T.rendelli Tilapia zellii (the redbelly tilapia ) ‫البلطي الزیلي او االخضر‬  Base color is brownish-olivaceous.  It has been introduced as a food fish or as a control of aquatic vegetation.  Where introduced, it sometimes becomes invasive, threatening the local ecology and species.  Tilapia rendalli (redbreast tilapia) ‫البلطي أحمر الصدر‬ This species very closely resembles the redbelly tilapia (T.Zellii) and the two are difficult to distinguish. The two have separate natural distribution but through introductions their ranges now overlap.  Substrate-spawners as fish lay their eggs on a rock or in a pit in the gravel.in the case of cichlids, the substrate means any surface to which the fish attaches its eggs a leaf, the roof of a cave, a vertical piece of slate, or even the aquarium glass once laid.  One or both parents will care for the eggs, regularly fanning them to keep well-oxygenated water passing over them, removing any eggs that show signs of fungus, and chasing away any fish that approaches.  Some species have to help their fry out of the egg case when they hatch: otherwise the young will die trapped inside.  In most cichlids, the female undertakes the bulk of caring for the youngsters, while the male takes a more active role in defending the territory.  In some species , male will guard a territory that includes several brooding females, a strategy known as harem polygyny Characters of cichlids as cultured fish: 1) They are disease resistant. 2) Reproduce easily. 3) Spawning occur more than once a year. It may reach five times a year. 4) Eat a wide variety of foods 5) Tolerate poor water quality with low dissolved oxygen levels. 6) Most will grow in fresh and brackish water and some well adapted to full strength sea water. 7) Can be cultured with other species as mullet and carp in poly cultures 2) Family cyprinidae:- A species of this family characterized by:-  Completely covered by scales as ……. common carp or silver and grass carp  Partially covered by scales as …….… mirror carp  Presence of one dorsal fin and one lateral line. Note:- common carp is characterized by toothless mouth but the lower pharyngeal bones have strong teeth for crushing food, stomachless with long intestine and presence of four barbless. common carp Grass carp Silver carp mi r r o r c a r p General characters of carp as cultured fish:- 1) High growth rate 2) Disease resistant 3) Acclimatize itself to change in water temperature rapidly. 4) Can be cultured in rice and duck farms. 5) Can be cultured in intensive and extensive aquaculture. Increased rice yield, the production of an additional (fish) crop on the same land, diversification of farm production, increased food security, and reduced need for inputs of fertilizer and pesticide. Because fish eat insects and snails, the systems may reduce mosquito- borne diseases and snail-born parasites. 3) Familly clariidae (air breathing catfish):- This group of fish characterized by :-  Absence of scales  Presence of eight barbels (four long dorsal barbels and four short ventral barbels)  Bonny hamlet shaped head  One soft dorsal fin E.G. Claries gariepinus (catfish) Characters of catfish as cultured fish:- 1) Resist diseases. 2) High growth rate. 3) Resist adverse environmental conditions as decreased dissolved oxygen due to presence of extra- respiratory organs. 4) family bagridae:- It characterized by:-  Absence of scales (scale-less)  Bony helmet shaped head  Eight barbels  The dorsal fin is divided into two parts (anterior part which is spiny. And soft rays and posterior part, which is adipose and fleshy).  E.G bagrus bajad Claries gariepinus Bagrus hayad 5) family mugillidae:- It characterized by:-  Presence of two dorsal fins (widely separated) The body has 6 to 10 dark narrow lines along the sides.  Absence of lateral line. Eg. Mugil cephalus, mugil capito and mugil auratus. Silver carp Mugil cephalus General character of mullet as a cultured fish:- 1) Can culture in fresh and marine water and temperate zone 2) Can culture with other species (poly culture) 3) High growth rate 6) family morrinidae:- It characterized by:-  Two narrow separated dorsal fins The body is completely covered by scales Presence of lateral line Slightly projected lower jaw. Eg. Stripped bass, sea bass and large mouth bass. Stripped bass large mouth bass  7) family angullidae:- It characterized by:- Body eel like Dorsal, tail and anal fin continuous.  Absence of pelvic fins.  The lower jaw is prominent.  E.G. Anguilla anguilla or eel fish.  3) According to water temperature 1) Cold water fish:- These are fish which are able to live, feed, grow and reproduce in water temperature less than10-15c◦. E.G. Salmon. 2) Temperate water fish:- These are fish which are able to live, grow and reproduce in water temperature between 15-35C◦, with optimum temprture22-25c◦. E.G. Oreochromis niloticus. 3) Warm water fish:- These are fish which are able to live, grow and reproduce in water temperature more than 35C◦. E.G. Oreochromis mossambicus. 4) According to water salinity:-  According to water salinity:- fresh water brackish water Marine water fish:- fish:- fish:- 1) Fresh water fish:- These are fish which are able only to complete their life stages in fresh water. The salinity of water ranges from 0-0.5ppt. E.G. Carp and clarias gariepinus. 2) Brackish water fish:- These are a certain types of fish which are able to life in water with different salinity in between fresh and marine water. The salinity of water ranges from 0.5- 33 ppt. E.G. Grey mullet. 3) Marine fish:-  These are the fish which are unable to live in fresh water. The salinity of water above 33 ppt.  E.G. Sea bass and sea bream. sparus aurata (sea bream) ‫سمكة الدنیس‬ 5) According to their feeding habits:- 1) Herbivorous fish:- These are fish which depend primarily in their feeding on grasses and algae. E.G. Grass carp. 2) Carnivorous fish:- Those fish depend in their feeding primarily on small fish and aquatic fauna.  E.g. Pike, sturgeon and nile perch. 3) Omnivorous fish:- Those fish obtain their food from both animal and plant origin. E.g. Mugil aurateus and common carp. Pike fish 6) According to feeding behavior:- 1) All water column feeder fish, as tilapia species. 2) Bottom feeder fish, as common carp, mugil auratus and catfish. 3) Surface feeder, as pike fish. 7) According to migration pattern:- Most fish species have a small home range to which they restrict most of their movements, but some fish are great traveler and move over long distance during their life. Therefore, fish could be classified into... 1) Non migratory :- Those fish spend their life in a restricted home range without actual travelling or long movement. These fish species are acting a vertical (up and down) or horizontal directions movement during their daily life searching for food. 2) Migratory:- Traveler fish could be travelling within the stream or between different streams, therefore could be classified into…  Migratory fish Diadromous Limnodromous Oceandromousf fish fish ish a) Diadromous fish:- Those fish travelling between marine and fresh water.  Running from marine to freshwater (anadromous) such as stripped bass or pacific salmon.  Running from fresh to marine (catadromous) such as freshwater eel. b) Limnodromous fish:- Those fresh water fish travelling within the fresh water stream. c) Oceandromous fish:- Those marine fish travelling within the marine water. The kind of migratory within the sea or ocean are usually associated with the environmental temperature. 8) According to their breeding:- 1) Egg laying fish (oviperous):- Fish bred by laying eggs, this group includes most of fish species and involves both ornamental fish. Fish subdivided into mouth breeding fish, as tilapia and nest breeding fish as salmon. Female forming the nest (redd) by vigorous movement of the tail to ground of the bottom to form a hallow 10-30 cm deep and 30 meter long. 2) Live breeding fish (viviperous):- These group include most of cartilaginous fish, where fertilization is internal. 9) According to scale cover:- 1) Completely scaled fish, as tilapia, grass and silver carp. 2) Semi-scaled fish or partially scaled fish, as mirror carp. 3) Scale-less fish, as catfish. 10) According to activity period:-  Diurnal fish as tilapia.  Nocturnal fish as common carp. 11) According to social behavior:-  Gregarious fish, as tilapia.  Solitary fish, as pike and black bass. THANK YOU