9 Animals with One Horn (Examples With Pictures)

Photo: Ched90 / Shutterstock

Unicorns may not be real, but we definitely have real-life substitutes out in the wild.

Whether it’s just a very oddly-shaped nose or a weapon for self-defense, horns are found in many species, and in this article, we’ll be taking a look at all the animals with one horn.

  • Indian Rhinos
  • Javan Rhinos
  • Rhino-horned Lizards
  • Unicorn Crestfish
  • Naso Fish
  • Narwhals
  • Cassowaries
  • Horned Silkworm
  • Rhinoceros Beetles

1. Indian Rhinos

Photo: Colin Eaton / Shutterstock

Scientific name: Rhinoceros unicornis

Unlike their cousins, the famed African animals with horns, Indian rhinos only have a single horn. We can find the horn in both male and female rhinos, developing it as they age (calves aren’t born with horns). 

The horn starts developing after about six years, and it’s made from keratin.

Indian rhinos are the biggest animals with a single horn, with the horn often exceeding 9 inches in length, with most extreme specimens recording 14-inch horns! They can weigh almost 7 pounds.

The primary purpose of the horn is self-defense, but except for tigers, rhinos in India don’t have natural enemies.

2. Javan Rhinos

Photo: Kurit Afshen / Shutterstock

Scientific name: Rhinoceros sondaicus

Javan rhinos are similar to Indian rhinos, but they’re often smaller, just like their horn. In fact, Javan rhinos have the smallest rhino horn, as it’s often shorter than 8 inches, with the longest recorded horn being 11 inches long.

See also  How Strong Are Elephants? [Strength Facts & Guide]

Also, unlike Indian rhinos, female Javan rhinos don’t have horns. They also don’t use their horn for self-defense, but rather for scraping mud. Unfortunately, these animals with small horns are critically endangered.

3. Rhino-horned Lizard

Photo: Ched90 / Shutterstock

Scientific name: Ceratophora stoddartii

The only reptile with a horn (barring a few snake species that have slight bumps on their heads), the rhino-horned lizard has a very obvious horn. It’s about two-thirds as long as the snout, with females having smaller horns.

It’s also possible for females to have no horns at all, which is why experts suspect that these small animals with horns could use them for mating. However, they can also be useful for deterring predators.

Since this species is endemic to Sri Lanka, there are no in-depth studies and much is yet to be learned about them.

4. Unicorn Crestfish

Photo: Sandra J. Raredon/Smithsonian National Museum of Natural History / Flickr / CC BY NC 2.0

Scientific name: Eumecichthys fiski

The only species in the Eumecichthys genus, this crestfish can be found all around the world, usually around 3300 feet in depth. Even though it’s very rare, it’s an easily-recognizable species because of its horn.

Possibly the only unicorn looking sea animal, the horn starts between their eyes, with its purpose still being unknown.

These animals with one horn on their head have ink tubes, shooting a black fluid to help them escape from predators.

5. Naso Fish

Photo: Tatiana Belova / Shutterstock

Scientific name (genus): Naso

This entire genus of fish is known as ‘unicorn fishes’, although our previous entry doesn’t belong here. They’re all similar because they’re all sea animals with one horn on head.

See also  Do Sharks Mate For Life? (Facts)

It is believed that these fish with horns use the length of their horns to establish dominance, but also to attract a mate.

It was also found that some species (Naso unicornis and Naso vlamingii) can change the color of their horn to draw attention to themselves.

6. Narwhals

Photo: VBakunin68 / Wikimedia Commons / CC BY SA 4.0

Scientific name: Monodon monoceros

Believe it or not, the famous horn of the narwhal is actually a tusk reaching incredible lengths. It can reach 10 feet, making narwhal horns the largest horns on an animal, at least when it comes to single-horned animals.

Two horns are possible, but they’re very rare (1 in 500 males). It is believed that they use their horns to establish dominance and attract mates, but they don’t use them for fighting.

Narwhals will also use them for exchanging information, as the horns have millions of nerve endings (they’ll rub one horn against another), and even to hunt fish. Even though they’re not essential to their existence, the horn is very useful.

7. Cassowaries

Photo: Johan Kusuma / Shutterstock

Scientific name (genus): Casuarius

Cassowaries have a very distinct cap on their heads which can grow up to 7 inches in length. That ‘cap’ is actually home for fiber with an acoustic function, but there are other uses too.

The casque could be a sexual characteristic, but it could also help protect the head in head-on collisions (something that happens when the bird is running). Either way, the cassowary is the only bird with a horn.

8. Horned Silkworm/Silkworm Moth

Photo: Joaquin Corbalan / Shutterstock

Scientific name: Bombyx mori

See also  Hyena Vs. Tiger: Who Would Win? [Strength Comparison & Facts]

Both silkworm moths and giant silkworm moths develop a horn when they’re still caterpillars.

They aren’t the only insects with horns, and their horns are actually harmless. Their purpose is to scare away would-be predators.

9. Rhinoceros Beetles

Photo: Vinicius R. Souza / Shutterstock

Scientific name (tribe): Oryctini

All rhinoceros beetles are similar, and they’re insects with the biggest horns. They’re usually the biggest beetles found in the area, with the European rhinoceros beetle being one of the biggest insects in Europe.

Only males have horns, and it is believed that their purpose is establishing dominance and attracting mates. This rule doesn’t apply to all beetles, as females of the Asian rhinoceros beetle also have horns, although shorter than male horns.

Read More Related Lists:

  1. 6 Animals with One Leg
  2. 10 Animals with No Teeth
  3. Top 20 Animals with Big Ears
  4. Top 9 Animals with Big Lips
  5. Top 16 Animals with Long Tongues List

James Ball

James has had a lifelong passion for animals and nature, tracing back to his childhood where he first began fostering intimate knowledge and connection with pet frogs and snakes. He has since honed this interest into a career as a trained Wildlife Biologist, specializing in Biogeography, sustainability and conservation. In addition to his professional pursuits, James maintains an active lifestyle, regularly indulging in outdoor activities such as hiking, and musical pursuits like playing piano and swimming.

Recent Posts