Earless Monitor Lizard

The Earless Monitor Lizard is a species of lizard that is native to the Indonesian island of Borneo in South-East Asia.

These lizards are semi-aquatic and can often be found swimming in streams and marshes or other sources of fresh water.

They are a unique species of lizard and are the only living species in its family. However, they are considered relatives of the true Monitor Lizards.

Earless Monitor Lizard
Image Credit: Reptiles4All

Earless Monitor Lizard Taxonomy

The family that the Earless Monitor Lizard belongs to is called Lanthanotidae. As there is only one species in this entire family, there is only one genus in the family.

The only genus in the Lanthanotidae family and the genus that the Earless Monitor belongs to is called Lanthanotus.

The scientific name for this species is Lanthanotus borneensis and there are currently no recognised sub-species.

The name Lanthanotus means hidden ear while the name borneensis refers to the island of Borneo where the lizard can be found.

Therefore, the scientific name for this species, Lanthanotus borneensis refers to the hidden ear lizard of Borneo.

The species was first described in 1878 by an Austrian herpetologist named Franz Steindachner.

Earless Monitor Lizard Description

The Earless Monitor Lizard is a large species of lizard that can grow to a length of almost two feet including their tail.

They are brown in color and are covered in bumpy ridge-like scales. These scales run the length of the lizard’s body and male them look like miniature dragons.

They lack an external ear opening which is where the lizards get the name the Earless Monitor Lizard.

However, they do have fully developed ear formations underneath their skin. Despite this, research has shown that they don’t respond well to auditory stimuli. 

They have small bright blue eyes on the side of their head and flared nostrils towards the top of their snout. These features make the lizard look even more like a dragon.

They have a prehensile tail and short limbs with long claws. 

Natural Habitat and Distribution

The Earless Monitor Lizard is only found on the island of Borneo which is located in South-East Asia.

The island of Borneo is shared between Indonesia and Malaysia, along with a tiny nation called Brunei. This lizard can be found in all three of these regions.

There is no recorded sighting of this lizard in the Southern part of the island with their range seemingly restricted to the regions further North.

It likes to live near sources of water such as streams and marshes at low elevations, typically being found at elevations below 300m.

They are commonly found in rainforest habitats but also take advantage of human habitation in areas such as agricultural land, palm oil plantations and rice paddies.

Earless Monitor Lizard Behaviour

The Earless Monitor Lizard is a nocturnal species meaning they are usually active at night and sleep during the day.

During the day, they will often retreat into shallow burrows close to their water source or hide under vegetation or decaying logs.

They are typically a solitary species but are known to live in close proximity to many other lizards if there is a limited supply of fresh water in a particular area.

They are opportunistic feeders and will eat a variety of different prey including insects, fish, tadpoles and even some turtle eggs.

They can actually eat while submerged under water which is rare for a lizard. They can do this by expelling water out through their nostrils, similar to what turtles do.