Skip main navigation

Bony Fish

Bony fish are in the Class Osteichthyes and have a wide range of adaptations that make them highly suitable for life below water.

Our next group of marine vertebrates are from the Class Osteichthyes and consist of the bony fish. Consisting of two subclasses, Actinopterygii – the Ray-finned fish, and Sarcopterygii – the Lobe-finned fish, consisting of over 28,000 species. 99% of all fish species belong to this order.

They can be found in marine and fresh water and have a range of characteristics that are adapted to life below water. These consist of: jaws with teeth, a bony skeleton, paired fins and gills covered by operculum, skin covered with scales, a swim bladder for buoyancy control, a homocercal tail (both top and bottom can be the same size), and a lateral line.

Can you think of a famous bony fish? Pop your answer in the chat below.

This article is from the free online

Life Below Water: Conservation, Current Issues, Possible Solutions

Created by
FutureLearn - Learning For Life

Our purpose is to transform access to education.

We offer a diverse selection of courses from leading universities and cultural institutions from around the world. These are delivered one step at a time, and are accessible on mobile, tablet and desktop, so you can fit learning around your life.

We believe learning should be an enjoyable, social experience, so our courses offer the opportunity to discuss what you’re learning with others as you go, helping you make fresh discoveries and form new ideas.
You can unlock new opportunities with unlimited access to hundreds of online short courses for a year by subscribing to our Unlimited package. Build your knowledge with top universities and organisations.

Learn more about how FutureLearn is transforming access to education