Turtle, tortoise, and terrapin are all similar reptiles in the taxonomic order Chelonia. They are all similar in that they have shells, but there are a few distinct differences. The difference between the three reptiles mainly comes from their habitat, though the terms can differ depending on where you live.

For instance, Americans describe the chelonians living near or in water as turtles, while people in the UK may refer to turtles as those that live in marine environments. Terrapins, on the other hand, is used to describe freshwater chelonians.

That said, there are few commonly accepted facts and distinctions between tortoises, turtles, and terrapins.

Tortoise

Tortoises are exclusive land-dwelling reptiles with a hard shell for protection. There are over 49 species of tortoise with varying sizes and shell lengths. Tortoises have a relatively long life, with some living for hundreds of years. Their club-like forelegs and elephantine hind legs help tortoises move on land with the extra weight. With an average walking speed of 0.3 miles per hour, tortoises move very slowly and are placid with a slow metabolism rate. 

Shell

Tortoises have domed and more rounded shells that are extra hard to withstand blunt trauma from land-dwelling predators. Tortoises will quickly retract their heads back into the shell when threatened. 

Feet and Leg Shape

Tortoises may be slow, but they spend most of their lives foraging thanks to their bowed hind legs and club-like forelegs. These are adapted to carry the extra weight in tiny but sure footsteps. Tortoise legs have a bent shape to stabilize their movement, especially in rocky terrains. Their toes have claws that come in handy when digging into the ground, searching for food. 

Swimming Ability

Tortoises cannot swim, but they can drift and float if the conditions are right; otherwise, they will simply sink and drown in deep waters. This is due to the heavy weight of their dome-shaped shells, making them less streamlined. Unlike turtles that have flippers, tortoises have clawed toes, which are less effective when it comes to swimming. 

Habitat

Tortoises spend their time on land, and their bodies are adapted for such habitats, unlike turtles adapted for both land and aquatic habitats. Tortoises lay eggs in underground burrows, with each burrow containing up to 12 eggs. Once the tortoise hatch, they usually hang around their mothers for about 80 days, unlike turtle hatchlings who are on their own from day one. 

Diet

Tortoises are herbivores, while turtles are omnivores. In the wild, tortoises feed on various fresh vegetables, fruits, and plants. However, some tortoise species are known to hunt for worms, insects and even birds depending on their natural habitats and nutritional requirements. 

Lifespan

Tortoises have a long lifespan, with some living for up to 200 years compared to turtles that live up to 40 years. Their slow metabolism means they burn less energy, and their cells don’t wear out fast, allowing them to continually replace old cells for much more extended periods than turtles. 

Turtles

Turtles are semi-aquatic reptiles, mainly found in seas, oceans, rivers, and lakes. They spend more time in water and come out on dry land to lay eggs. They tend to swim in freshwater water sources, and some may live a double life; in water and land.

Unlike terrapins and tortoises, they have webbed feet combined with a streamlined body and long flippers, which enable them to swim faster. Unfortunately, many turtle species are prized for their meat and eggs and face low reproductive rates, making survival a challenge.

Appearance

One of the main differences between turtles and other chelonians is the shell shape. Turtles are more streamlined with much flatter shells, which allows them to swim more swiftly and faster. Besides, their limbs look more like flippers, which is different from turtles whose sturdy legs help them move on land.  While flippers are for swimming, it’s difficult for them to move on dry land, such as when they want to lay eggs on the edges of rivers and lakes.

The exception to this rule is the box turtles and some mud turtles with dome-shaped shells who spend more time on land than in water.

Diet

Different turtles have different diets where some are herbivores, others omnivores, and some are carnivores. Many turtles are omnivores and feed on aquatic algae, seaweed, and small creatures. In captivity, you can buy them commercial food, but they need a variety of other foods such as leafy greens, shrimp, fruits, and more. 

Size

While turtles grow more slowly, they can attain large sizes. Attaining a large size is a survival adaptation that helps them deal with predators. Besides, a large body is better at retaining heat and can deal with cooler temperatures much better. It’s why more giant turtles are occasionally seen in British waters because their large bodies keep the heat they require to navigate colder waters.

Personality

Turtles are calm, gentle, and quiet creatures. When you spend more time with them, you’ll realize they are shy and slow and don’t like chaos in any form. However, they may fight over food with other turtles or during the mating season. For owners with pet turtles, you might realize they try to retract in their shells whenever there is a loud noise, bright lights, or any sudden disturbance that scares or stresses them out. Turtles have relatively small brains compared to their size.

Habitat

Most turtles are semi-aquatic and will spend more time in the water because they spend most of their time hunting for food. If you have a pet turtle, you need more water, at least 50 gallons per day. You also need a filtration system to remove the waste and keep the water clean. They also need space for basking, ensuring the UVB lamp is on to provide adequate lighting. Aquatic plants will benefit the turtle nutritionally and help keep the tank aesthetic.

Scute shedding

One of the distinctions of turtles from other chelonians is they shed to remove their scutes and make room for new scutes. Tortoises don’t shed anything, and their keratin keeps growing without shedding. Turtles can be seen basking in the sun to dry off their scutes as a way to help them flake off. Sometimes, turtles can be seen rubbing their shells on objects like rocks to try and remove the scutes.

Terrapins

The word terrapin is the Indian name for a little turtle. In the US, the word terrapin is rarely used (if ever used). In much of Europe, terrapin describes chelonians residing in freshwater, while turtles live are ocean-going chelonians residing in marine environments. Still, terrapins closely resemble turtles and hence the confusion with them.

Terrapins have a hard calcareous carapace which is part of their ribs. Since they are semi-aquatic, their carapace is less streamlined to thrive in both worlds. Unlike turtles, terrapins are outgoing, aggressive towards predators, and can bite.

Here are a few things that make terrapins different.

Shell

Unlike turtles, terrapins have a curve carapace that facilitates swimming. There’s a difference in that terrapins do not have flippers like turtles, making the legs similar to those of tortoises. However, the legs have sparingly good claws for climbing, and males are particularly gifted in this area. In turtles, the toes and toenails are not predominant.

Personality

If you observe terrapins keenly, you will realize that they have a unique personality. The main reason for their popularity as pets, they don’t mind being handled and are so adorable. On the other hand, they will let you know when they need space. Terrapins are generally friendly and rarely turn aggressive unless they feel threatened. Without enough space for themselves, they may nip.

That said, terrapins are highly sociable creatures that won’t mind living with mates in the cage. In fact, you should not keep a terrapin alone. As long as space is available in the aquarium setup, make sure you have more than one. Still, a terrapin can live alone and be content when space is limited. Do not overcrowd many terrapins together as they can turn aggressive towards each other. 

Habitat

Terrapins are semi-aquatic and live on freshwater or slightly salty water in ponds, waterholes, or lakes. Your terrapin should have access to both land and brackish water in captivity. The water in the tank needs to be at least three times the height of the shell to allow them to submerge as needed. Ensure you have a filtration system because terrapins are messy and will get the water dirty quickly. Terrapins also benefit from having some coral as a substrate because it’s full of calcium needed for their shells. They also require a basking spot where they can stretch and bask. To allow the terrapins to convert vitamin D in their bodies, you need proper lighting. Unlike terrapins, turtles are happy to live alone.

Size

In the past, terrapins got themselves a bad name for growing so large. Owners would import red-eared terrapins on for some to grow to large up to 12 inches in shell length, making it challenging to provide all the space. Not all terrapins grow that large though, a few species nowadays do not exceed 6 inches, which is more manageable. Adult males are significantly smaller than their female counterparts both in weight and shell length. However, note that some terrapin species like snappers can grow over 60 cm and weigh over 50 pounds.

Wrap Up

What’s the difference between turtles, tortoises, and terrapins? While there are a handful of pronounced differences between the three, the debate is quite complicated because the difference is geographical.

Turtles refer to the order of reptile Testudines, mostly limited to aquatic species only. Tortoise describes non-swimming species of Testudines, while terrapins are any small species of tiny, semi-aquatic, hard-shelled turtles.