Bony fish and Cartilaginous fish

35,500 species of fish have been documented by science. Many new species have yet to be discovered, and many more may never be discovered at all. In the years 2010-2019, 3,920 new species of fish were discovered, which is a high rate of new species discovery. It is estimated that there are more fish species than any other group of animals.

After billions of years of evolution, the forms of fish we see today—bony fish and cartilaginous fish—have arisen. On the surface, these two fish look similar, but they aren’t. 

There is a wide variety of fish species in existence across the globe. There are around 28,100 distinct species of fish known to science. This hierarchical classification of all living things is known as the class, species, family and so on and so forth. In addition to the many different types of fish, there are also bony fish and cartilage fish. It’s possible to tell them apart based on their social standing, physical traits, and so on. We’ll learn about both types of fish in this post, and we’ll uncover the main distinctions between cartilaginous and bony fish.

Bony Fish

What are bony fish?

Bony fish, also known as Osteichthyes, is a vast fish with diversities. Fishes belonging to this group primarily have skeletons composed of bone tissue. Most of the fish are members of Osteichthyes. It is a diverse and abundant group with 45 orders, more than 435 families, and 28,000 species. 

What are the characteristics of bony fish?

Bony fish have a relatively stable pattern of cranial bones, rooted, medial insertion of mandibular muscle in the lower jaw. Dermal bones cover the head and pectoral girdles. 

Early bony fish had simple lungs, which helped them breathe in low-oxygen water. However, now it has evolved into swim bladders, which helps create a balance between sinking and floating. Bony fish also have an operculum, allowing them to breathe without swimming. 

What are some examples of bony fish?

The Ocean Sunfish is known to be the heaviest bony fish globally, and King of Herrings is known to be the longest bony fish in the world, which is a type of oarfish. 

Cartilaginous Fish 

What are Cartilaginous fish?

Fishes with a skeleton made of cartilage rather than bone are called cartilaginous fish. These fishes fall into the category of Elasmobranchs. 

What are the examples of cartilaginous fish?

Examples of these types of fish are sharks, skates, etc. 

What are the characteristics of cartilaginous fish?

Cartilaginous fishes have gills that open through slits in the ocean. Different numbers of gill slits are present in different shark species. Cartilaginous fishes also breathe through spiracles, situated on top of the heads of all skates and rays, and some sharks.  These spiracles (openings) help the fish to rest on the bottom of the ocean and draw oxygenated water in through the top of their head. This allows them to breathe without breathing in the sand. Skins of cartilaginous fish are covered with placoid scales or dermal denticles.

Difference between Bony Fish and Cartilaginous Fish

Conclusion

Thus, knowing the basic differences between bony fish and cartilaginous fish is important to indulge in further knowledge about these two types. One of the basic differences between these two types of fish is in the composition; one type is entirely made up of bones, while the other is made up of cartilages.