With about 356 species of turtles found worldwide, identifying a particular species of turtle can take a bit of effort. Turtles come in a variety of sizes and can live in both saltwater and freshwater environments, as well as on land. Tortoises are a particular family of land-dwelling turtles, with a few differences in appearance that help us tell them apart from other turtle species.
Whether you’re a do-gooder trying to determine the type of turtle you saved from a roadside or an experienced scientist conducting research, the first step in identifying turtles is learning the names and features of their major body parts.
In this article, we’ll discuss the major parts of the turtle’s body and how they can help you identify what kind of turtle you’re dealing with.
The Major Turtle Body Parts
The turtle’s head is found on the front part of their body. Most species of turtles can pull their heads back into their shells as a defense mechanism. Some species, specifically sea turtles, can’t do this and are more at risk of injury than their land relatives. A turtle’s head contains several distinct parts including:
Turtles use their eyes for sight just as humans do. Most aquatic turtles have eyes higher up their head than land turtles do. The quality of a turtle’s vision varies but it is believed that they can see colors. Turtles have an upper and lower eyelid, as well as a third eyelid, also called a nictitating membrane, that slides up and back to help clean and protect their eyes.
The turtle’s beak is located on the front of their head and contains their nostrils and mouth. Inside their mouth, they have ridges instead of teeth for chewing their food and a tongue, used for swallowing food. Nostrils are usually small slits or holes on the tip of the turtle’s beak. Turtles have a good sense of smell, even in the water.
Turtle’s don’t have visible ears. Instead, they have a thin skin called a tympanic membrane at the back of their heads, which covers their inner ear bones and conducts sounds and vibrations.
A turtle’s neck connects its head to its body. In most species, it can pull back into the shell along with the head.
The most famous part of the turtle’s body is the shell. A turtle shell is divided into two parts: the carapace and the plastron.
The upper shell of the turtle is called the carapace. A turtle’s inner shell is made of bones. The outer shell of most turtles are covered in hard scales or scutes. Some turtle species have tough skin covering their shell instead.
Turtle scutes are made of keratin, just as human hair and nails are.
The shape, color, and pattern of the carapace are some of the key methods of identifying different turtles and tortoises. Land turtles usually have rounder and heavier shells than aquatic turtles, who are thinner and more streamlined for easier swimming.
Bridges are made of bone and run along the sides of the turtle, connecting the upper and lower parts of the shell.
The turtle’s lower shell, the plastron, is also made up of scutes, which are also named for their location.
Some turtle species can clamp their head and tail scutes tightly into the carapace, sealing themselves inside for protection.
The turtle’s skin is also made of keratin and covers the tail, limbs, and head. The texture and thickness of the skin vary based on the species of turtle.
All turtles have four limbs but the appearance of those limbs depends on where the turtle lives.
Land turtles have thick, stubby legs and feet with claws for digging. Aquatic or semi-aquatic turtles also have four legs but they usually have webbed feet and long claws and a few have flippers. Sea turtles, who spend almost their entire lives beneath the waves, have flippers instead of legs and different shaped claws.
At the back of the turtle, you’ll find their tail. The size and length of the tail vary based on the species of turtle and whether they are male or female. In fact, tail size is one way to tell the difference between adult male and female turtles. Males generally have longer and thicker tails because their tails also contain their reproductive organs.
Turtles are fascinating reptiles, whether observed in the wild or kept as pets. Knowledge of the turtle’s body parts can help not only in identifying different species but in improving the level of care you give your pet turtle or tortoise.
Featured Image Credit by M.E. Parker, Shutterstock