Lizards are a fascinating group of reptiles that come in a huge variety of shapes, sizes, and colors. With over 6,000 species identified so far, lizards have adapted to thrive in diverse habitats across every continent except Antarctica. But how many different types of lizards are there actually?
Main Types of Lizards
There are 5 main groupings that all lizards can be divided into:
Geckos are characterized by their large eyes, lack of eyelids, and special toe pads that allow them to climb smooth surfaces. There are around 1,500 species of geckos worldwide, making them the most diverse group of lizards. Some of the most popular gecko species kept as pets include leopard geckos, crested geckos, gargoyle geckos, and mourning geckos.
Iguanas are large lizards from the Iguanidae family found throughout the Americas and parts of the Caribbean. There are around 40 species of iguana including the green iguana and spiny-tailed iguana. Iguanas are herbivorous, eating leafy greens, fruits, and flowers. The green iguana and other large species are popular exotic pets.
Skinks make up the largest family of lizards with around 1,500 known species. Most skinks have elongated bodies and legs with smooth, glossy scales. They are found in a variety of habitats worldwide. Some well-known skinks include the blue-tongued skink, prehensile-tailed skink, and five-lined skink.
Agamas are lizards from the Agamidae family found in Africa, Asia, and Australia. There are over 350 species of agamas including popular pet species like the bearded dragon. Agamas have triangular heads and long tails. Many lizard species have the ability to change colors.
Monitors belong to the Varanidae family with around 80 species found throughout Africa, Asia, and Australia. Monitors range greatly in size from the tiny short-tailed monitor to the infamous Komodo dragon, which can reach 10 feet long. Monitors are characterized by their long necks, muscular bodies, strong legs, and long tails.
Other Significant Lizard Groups
Beyond the 5 main types, there are a few other important lizard groupings:
- Chameleons – Old World lizards with specialized feet, turrets eyes, and a long tongue. Famous for color changing abilities. Around 200 species.
- Anoles – Small lizards from the Americas typified by the green anole. Around 400 species, making them one of the most diverse lizard groups.
- Lacertas – Commonly known as wall lizards or true lizards. Around 320 species found throughout Europe, Asia, and Africa. Often green or brown in color with divided scales on bellies.
- Night lizards – Nocturnal lizards from the Xantusiidae family. Around 34 species native to North and Central America. Have vestigial legs evolved for burrowing.
- Legless lizards – Lizards without legs that resemble snakes. Around 200 species worldwide. Examples are slowworms and glass lizards.
- Swifts – Small spiny lizards from the Scincidae family. Over 300 species found in Africa, Asia, Australia. Resemble skinks.
How Many Types of Lizards Are There ?
Given all of these major groupings and smaller subgroups, there are estimated to be over 6,000 lizard species alive in the world today. New species are still being discovered each year, especially in biodiverse tropical regions. The exact number of lizard types may never be fully known as many secretive species likely remain undiscovered in remote habitats.
Some key takeaways on the types of lizards that exist globally:
- There are 5 main families: geckos, iguanas, skinks, agamas, and monitors.
- Significant other groups include: chameleons, anoles, lacertas, night lizards, legless lizards, and swifts.
- The total number of identified lizard species sits between 6,000 and 7,000.
- Geckos have the greatest diversity with around 1,500 species.
- New lizard species are continually found each year, especially in the tropics.
- The full diversity of lizard life may never be fully documented.
The Fascinating Adaptations of Lizards
What makes lizards so diverse is the incredible array of adaptations they have evolved that allow them to thrive in habitats ranging from deserts to rainforests. Here are some of the most notable lizard adaptations:
- Color changing – Chameleons and anoles can rapidly change their skin color using specialized pigment cells for camouflage and signaling.
- Toe pads – Geckos, anoles and some skinks have sticky toe pads that enable climbing on the smoothest surfaces.
- Burrowing – Many lizards like skinks and legless lizards have streamlined bodies and reduced limbs adapted for digging and living underground.
- Swimming – Sea snakes and marine iguanas have paddle-like tails and the ability to excrete excess salt from glands to survive in the ocean.
- Gliding – Flying lizards like the flying dragon can glide through the air using winglike flaps of skin forsteering and stability.
- Venom – Gila monsters, beaded lizards, and Komodo dragons have toxic venom they use when hunting prey.
- No legs – Legless lizards like glass lizards have evolved to lose their limbs for rapid burrowing. Their snake-like shape helps hunting.
- Frill – Frilled lizards can open the large frill around their neck when threatened to appear more intimidating to predators.
- Horned – Horned lizards have sharp bony protrusions on their heads and bodies that deter predators. Some can even shoot blood from their eyes!
- Prehensile tail – Chameleons and some skinks/geckos have a curled tail that can grip branches like a fifth hand.
This huge diversity of adaptations is why lizards thrive in so many environments worldwide. Their flexibility and variety is a key reason there are so many types of these incredible reptiles.
In summary, the major types of lizards include geckos, iguanas, skinks, agamas, and monitors. Along with smaller groups like chameleons and anoles, there are likely between 6,000 – 7,000 identified lizard species globally. However, new species are continually being discovered each year. Lizards have adapted into an amazing array of forms to thrive everywhere from deserts to trees to underground. Their diversity showcases the wonder of evolution through specialized adaptations. Looking across all the types, it’s clear lizards are a successful group filling important niches across ecosystems worldwide.
Are alligators and crocodiles considered lizards?
No, alligators and crocodiles are not considered lizards. While they share some similarities, such as reptilian features, they belong to a different reptile group known as Crocodylia. Lizards belong to the order Squamata, which is distinct from crocodilians.
How many lizard species are found in North America?
North America is home to over 200 lizard species. These species vary in size, appearance, and habitat preferences. They can be found in diverse ecosystems, ranging from deserts to forests, making North America a region with significant lizard diversity.
What are the most common types of pet lizards?
Some of the most common pet lizard species include Bearded Dragons, Leopard Geckos, Crested Geckos, Ball Pythons, and Anoles. These lizards are popular among reptile enthusiasts due to their manageable size, ease of care, and fascinating behaviors.
Are there any venomous lizard species?
Yes, some lizard species are venomous. The Gila Monster and the Mexican Beaded Lizard, both found in North America, are examples of venomous lizards. However, venomous lizards are relatively rare compared to venomous snakes and other reptiles.
Do all lizard species have legs?
No, not all lizard species have legs. While the majority of lizards are quadrupeds with four legs, there are exceptions. Legless lizards, such as the European Legless Lizard, resemble snakes but are classified as lizards due to their evolutionary lineage.