Colubridae

Many snakes belong to one big group.

These snakes live on almost every land. They live in forests and deserts. Some even live in the water.

They come in many colors and sizes. Most are shy and do not hurt us. Some have small teeth in the back of their mouths. They use these teeth to eat. Most of these snakes lay eggs. Some snakes in this group give birth to live babies.

They are a very large family of snakes.

Colubridae is a very large family of snakes.

It is the biggest family of snakes in the world. These snakes live on every continent except Antarctica. They live in many places. Some live in deserts or mountains. Others live in water or trees.

They come in many shapes and colors. Most of these snakes are shy. Most do not have venom. Venom is a liquid that can hurt animals. Some snakes in this group have rear fangs. These are small, grooved teeth in the back of the mouth. To use them, the snake must chew on its food.

Most colubrids are oviparous. This means they lay eggs that hatch later. Some species are viviparous. This means they give birth to live young. Scientists found old fossils of these snakes in Georgia. They also found fossils in Thailand. These fossils are from a time called the Late Eocene. This tells us these snakes have been around for a very long time.

Colubridae is the largest family of snakes in the world.

This group contains 249 different genera. These snakes live on every continent except for Antarctica. They can be found in many different homes. Some live in dry deserts or high mountains. Others live in water or high up in trees.

Because they live in so many places, they have many body styles. They come in many sizes, colors, and patterns.

Most colubrids are shy and harmless to people. Most of them do not have venom. However, some species do have special teeth. Some have opisthoglyphous teeth, which are called rear fangs. These are small, grooved teeth at the back of the upper jaw.

To use these fangs, the snake must chew on its prey. This chewing motion helps it inject venom. A few snakes, like the boomslang, can cause serious bites. Other snakes have proteroglyphous teeth located at the front of the mouth.

Scientists have studied these snakes for a long time. In the past, people used this family as a "wastebasket taxon." This means they put snakes in this group if they did not fit elsewhere. Recent research uses molecular phylogenetics to study their DNA. This helps scientists group them more accurately. As of May 2018, experts recognize eight different subfamilies. These include Colubrinae, which has 93 genera, and Dipsadinae, which has over 100.

We can learn about their history through fossils. The oldest fossils come from the Late Eocene epoch. Some fossils were found in Thailand. Other fossils, called Nebraskophis, were found in Georgia in the United States. These fossils show that colubrids have been around for a very long time. Other fossils were found in the Ringold Formation in Washington. These included species like Elaphe pliocenica and the extinct Tauntonophis.

There are different ways these snakes grow their young. Most colubrids are oviparous. This means they lay eggs that hatch later. The number of eggs depends on the size of the snake. Some snakes are viviparous. This means they give birth to live young instead of laying eggs. This happens in the Natricinae and Colubrinae subfamilies. This variety helps them survive in many different environments around the world.

Colubridae is the largest family of snakes in the world.

This massive group contains 249 different genera. These snakes are found on every continent except for Antarctica. They live in many different environments. Some species live in deserts or high mountains. Others live in water or in trees. Some even live underground or in brackish waters. This diversity allows them to thrive in many different habitats.

Most colubrids are shy and harmless to humans. The vast majority of these snakes are not venomous. Even when they do have venom, it often does not impact mammals. However, some bites can become medical emergencies. The South African boomslang and twig snakes are known for dangerous bites. Asian keelback snakes are also noted for causing harm. These specific species have caused the most confirmed human fatalities.

Some colubrids use special teeth to hunt. These snakes are described as opisthoglyphous, or rear-fanged. This means they have short, grooved fangs at the back of the upper jaw. These fangs are often sharp on both the front and back edges. To inject venom, the snake must chew on its prey. This chewing motion creates a cutting action against the tissue. This trait may be an evolutionary precursor to the front fangs found in vipers.

Other colubrids are proteroglyphous, meaning their fangs are at the front of the upper jaw.

Colubrids have many unique physical traits. They have limbless bodies and a reduced or absent left lung. Some possess a tracheal lung to help them breathe. Their anatomy includes well-developed oviducts for reproduction. Their upper jaw bones, called premaxillaries, lack teeth. The maxilaries are oriented longitudinally with teeth that are either solid or grooved. They also lack cranial infrared receptors. Instead, their optic foramina typically traverse specific sutures in the skull.

These snakes have different ways of reproducing. Most colubrids are oviparous, which means they lay eggs. The size of the egg clutch depends on the species and size of the snake. However, some subfamilies are viviparous. This means they give birth to live young. This occurs in the Natricinae and Colubrinae subfamilies. The number of offspring born live also depends on the specific snake species.

Scientists have changed how they classify these snakes over time. In the past, Colubridae was called a "wastebasket taxon." This meant scientists put snakes in this group if they did not fit elsewhere. Some snakes in the group were actually more related to elapids. Recent research in molecular phylogenetics has changed this. This study of DNA has helped create a monophyletic clade. This means the current group shares a common ancestor.

As of May 2018, there are eight recognized subfamilies. The Dipsadinae subfamily is very large with over 100 genera. The Colubrinae subfamily contains 93 genera. The Natricinae subfamily includes 36 genera. Other subfamilies include Sibynophiinae, Pseudoxenodontinae, Grayiinae, and Calamariinae. Some subfamilies are still being determined by researchers. This classification helps us understand the complex relationships between different snakes.

The history of colubrids is visible in the fossil record. The earliest fossils date back to the Late Eocene epoch. Some indeterminate vertebrae were found in Thailand. Other fossils, belonging to the genus Nebraskophis, were found in Georgia, USA. Because these fossils appear in North America so early, scientists think they may have originated even earlier. Other fossils from the Pliocene were found in the Ringold Formation in Washington. These included the extinct genus Tauntonophis and species like Elaphe pliocenica.