Osteichthyes By: Ashley Burgess and Brandon Rose

Phylogenetic tree

Taxon Characteristics The class Osteichthyes fits into the kingdom animalia and the phylum chordata. To be classified into the Osteichthyes class the fish have to have cranial bones and mandibular muscles in the lower jaw. The head is covered in large dermal bones. The labyrinth in the inner ear contains large otoliths. The braincase is usually divided into anterior and posterior sections divided by a fissure. They also are able to see in color, unlike most other fish.[citation needed]citation needed Bony fish have no placoid scales. Mucus glands coat the body. Most have smooth and overlapping scales of that are ganoid, cycloid or ctenoid.placoid scalesganoidcycloidctenoid

Taxon Characteristics Bony fish normally have swim bladders. This helps the body have a balance between sinking and floating. These are missing in many species and have developed into primitive lungs in lungfishes. Bony fish have an operculum which helps then to breath without needing to swim. Bony fish can also see in colour. Most fish have smooth overlapping scales that are ganoid, cycloid or ctenoid.

This is the Pacific Goliath Grouper. It is an example of a bony fish. It can exceed 660 lbs.

This is the Ocean Sunfish. It is the largest Bony fish in the world.

This is the giant oarfish. It is the longest bony fish in the world. Can reach 11 metres in length.

The Atlantic blue marlin is another very large bony fish.

Classification of Ocean Sunfish Kingdom: Animalia Phylum: Chordata Class: Actinopterygii Order: Tetraodontiformes Family: Molidae Genus: Mola Species: M. mola

Classification of Oarfish Kingdom: Animalia Phylum: Chordata Class: Actinopterygii Order: Lampriformes Family: Regalecidae Genus: Agrostichthys Species: parkeri

Classification of Atlantic blue marlin Kingdom: Animalia Phylum: Chordata Class: Actinopterygii Order: Perciformes Family: Istiophoridae Genus: Makaira Species: M. nigricans

Life cycle of the Atlantic blue marlin The Atlantic blue marlin reproduces sexually and often release over seven million eggs at once. The Atlantic blue marlin reaches sexual maturity at age two to four years of age. It then reproduces. Not all Atlantic blue marlin reach sexual maturity.

Anatomical and physiological features The anatomical and physiological features that all of the animals in our taxon have are Fins for swimming. Boney fish wouldn’t be able to move at all without fins. Their fins help them to get food and they are their only way of getting around. They all also have jaws for eating.

Circulation system The circulation system of bony fish consists of heart, blood and blood vessels. This is called a “closed system”. The way this system works is the veins throughout the whole fish transport blood to different parts of the body just like a humans circulation system would.

Circulation System A fish’s heart only has one ventricle and one atrium. It is a single loop system. The fish’s heart pumps blood to the gills then to the body and back to the heart. The heart pumps deoxidized blood to the gills. It then becomes oxidized and then goes through the body. The body uses the oxygen from the blood so it is now deoxidized and sent back to the heart.

Gas exchange The way our taxon does gas exchange is through their gills. Fish take in water through their mouth that contains O2. The O2 goes into the bloodstream. The CO2 from the blood stream is released with the water through the fish’s gills.

Digestion of food Bony fish use their jaw and/or teeth to eat their food which then goes down the throat into the oesophagus and into the stomach. Gastric juices, enzymes and acids then begin to break down the food. The food then proceeds to the intestines. To finish being digested.

Excretion of waste The bony fish has a one way system. After it digests the food and it has made its way through the intestines it is excreted through the anus of the fish.

facts Osteichthyes includes the largest number of living species of all scientific classes of vertebrates, more than 28,000 species.

facts The largest bony fish is the ocean sunfish and it can grow to a total of 10 feet across!

facts The oldest known fossils of bony fish are about 420 million years old.

Changes in Classification Bony fish were first classified under aquatic by Aristotle. Then Carlous Linnaeus changed the classification world and classified animals by structural characteristics. Since being classified under aquatic, fish have been separated into kingdom: Animalia, Phylum: Chordata and class: Chondrichthyes or Osteichthyes. This system is much more organized then the original system created by Aristotle. There have been no large changes other then this to the classification of bony fish.

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