Are Otocinclus Scaleless?

by | May 23, 2022

Otocinclus Scaleless

If you are planning an addition to your aquarium, and you are considering Otocinclus, but you are wondering if they are scaleless, or you just want to know more about this beautiful species, you have come to the right place.

There are many things about the bottom dweller you need to know.

One of the things most people are curious about when it comes to the Otocinclus is if they have scales.

This blog post will answer that for you.

Are Otocinclus Scaleless?

To answer your question, Otocinclus doesn’t have scales.
Instead, they have rows of armor plating covering their bodies.
These plates insulate them from attack by other fishes.

Unfortunately, the plates do not stop chemicals, salts, or even pesticides from entering deep into their body.

The lack of scales is one of the reasons for their susceptibility to fish diseases like Ich, body slime, eye cloud, tail rot, etc.

What are Scales?

The word scale comes from an old French ‘escape’ that translates to a shell pod or husk.

Scales are protective shields that grow from the body of fishes and shelter them from diseases.

They are composed of thin pieces of bones and can be either round or spiky.

The scale protects the fish’s inner body structures and organs.
Fish scales have epithelial layers, a kind of slime that further protects the fish.

You can deduce the age of a fish by the scale of the fish. This outer layer of the scale produces the mucus you feel when you touch a fish.

This mucus helps the fish escape the grasp of other fishes who want to feed on them. It also allows it to evade bacteria and other poisonous substances in the surrounding.

The Importance of Scales

Over thousands of years, fishes, like other animals, have adapted and developed mechanisms to help them cope with the environment and predators.

One of the things that developed was the scales. Scales are a good feature of fish for two main reasons: protection and movement.

You can think of the scale as a shield protecting the fish in battle and stopping the invasion of bacteria infection.

It also serves a hydrodynamic purpose by reducing friction with water when the fish is swimming.

Fishes without scales are exposed.

Fishes like the Otocinclus and other types of fishes without scales are not adequately equipped to battle the elements.

Without the shield of scales, they are at the mercy of diseases, especially bacterial infections like Ich and Rot.

If you own an Oto, you will also notice many marks of injuries on its body. These are due to scratching against the substrate and other decorations without the added protection of scales.

If you have an Oto as a pet, you need to provide it extra care and watch out for infections.

One of the disadvantages of owning an Oto is how easy it is for them to contract Ich.

Other scaleless fishes like Otocinclus

Otocinclus are not the only fish without scales.

Most types of catfish also lack scales. Many develop alternative protections, like tough skin or armor plates. Apart from catfishes, other fishes without scales include Anglerfish, most Eels, Manderinfish, Jawless Fish, BoxFish, and Seahorses.


Otocinclus are scaleless, but there are not the only species without scales.
Many others like them don’t have the protective functionality of the scale, but still manage to survive.
Of course, the scale has its functions and most times acts like a buffer against the elements in the ecosystem, but the Otocinclus can survive without it.

You only need to pay extra care to it and ensure you constantly change their water and keep the aquarium clean always.

About Me

Hi, I am Sarah! At Amado Pets we are passionate about pets and love sharing our knowledge and research with you. We strive to be the ultimate resource for you to learn all that you can about caring for your pet!