We often use newts and salamanders interchangeably. However, they are two distinct amphibians. In this article, we will discuss eight differences between them. In the end, we also discussed the environmental threats they encounter in their natural habitats.
Firstly, newts are a type of salamander that belongs to the family Salamandridae. They are aquatic species, while salamanders, in general, are semi-aquatic.
To avoid further confusion, remember that all newts are salamanders, but not all are newts. Find more of their differences below.
8 Differences Between A Salamander And A Newt
1. Salamander and Newt: Classification
These soft-bodied creatures are amphibians. However, all newts are salamanders, but not all salamanders are newts. Salamanders are a complex species consisting of other amphibians that are aquatic and terrestrial species.
Both of them belong to the family Salamandridae in the Caudata order. The family contains the true salamanders and newts, with newts belonging to the subfamily Pleurodelinae. True salamanders have a subgroup of salamanders called sirens.
Sirens are salamanders with lungs and gills that don't develop past their larval stage. You differentiate true salamanders by their tails and brightly colored skin. Their skin is a warning of their toxicity. You will mostly find salamanders in western North America, South America, China, and other temperate areas.
Read more: Salamander Facts.
2. Size and Appearance
Salamanders and newts have varying sizes and appearances based on their species. For instance, a mature eastern newt is 7 cm to 12.4 cm long, while a giant salamander can grow up to 2 feet long.
The Japanese giant salamander grows up to 5 feet long, while the great crested newt grows up to 17 cm. It is worth mentioning that salamanders are bigger than their cousins, the newts.
Considering the species of salamanders and newts mentioned previously, we can tell they all look different. The giant salamanders of Florida have a smooth, slimy, and scaleless body. They are often dark gray but sometimes have black or gold flecking on their backs.
They have an elongated body with tiny limbs. Their limbs look like they are almost disappearing. The two-toed salamander, one of the larger salamanders, has two useless front and hind legs. Each limb has two toes. Another giant salamander has normal-sized front limbs with four toes but doesn’t have hind limbs.
Eastern Newts, on the other hand, have a yellowish-brown to greenish-brown body with black-bordered red spots. The color of their belly is yellow and has black spots. They have a slightly wet body and rough skin.
Another salamander with a unique appearance is the spotted salamander. It is dark brown or black with yellow or orange spots on its back and sides. It has a broad head and vertical grooves on both sides of its smooth skin. The spotted salamander has a maximum length of 25 cm.
3. Habitat
Salamanders tend to live in moist habitats. Salamander species develop in water bodies and breathe with their gills. As they mature, the salamander species develop lungs and start breathing air. Terrestrial salamanders tend to live in wet habitats in forests2, while aquatic salamanders live in vernal pools, streams, large lakes, rivers, and spring seepages.
You will find the Japanese giant salamanders in cold, fast-flowing waters in forests. The spiny salamander lives in temperate forests, freshwater marshes, and ponds in a small area of Zhejiang province, China.
Salamanders and newts live in different environments despite being in the same family group. Since newts are semi-aquatic, they prefer to stay near stagnant water bodies like ditches, slow streams, ponds, or flooded meadows for reproduction. Newts live in humid areas like grassland and wetland habitats on land.
You'll find salamander and newt species in northern temperate and Neotropical areas. The United States is home to most of the salamander and newt populations. Also, some salamanders live in caves and mountain regions. For instance, the arboreal salamander prefers to lay eggs in tree cavities and wait out the summer season. They have evolved to climb heights up to 60 feet.
4. Diet
Salamanders and newts are meat eaters and opportunistic feeders. They often switch between being active predators or using an ambush to catch their prey. They consume small aquatic and terrestrial invertebrates.
They eat frog tadpoles, snails, slugs, worms, and crustaceans. Mature newts often feed on smaller newts. Salamanders eat fish and flying insects trapped in water. Many salamanders and newts have tiny teeth for grasping food instead of chewing. The California newt has an adhesive texture on its tongue that extends out to catch prey.
5. Tail
One of the significant differences between a salamander and a newt is their tails. Newts have tails shaped like paddles. It is arched at the top and rounded, while salamanders have longer and tapered tails. Salamanders are often mistaken for spring lizards because they have similar tails. A newt's tail is more adapted to the aquatic lifestyle, while a salamander’s tail is more suited for terrestrial living.
6. Feet
Another way to differentiate between a salamander and a newt is their legs. They grow their limbs in different ways. Salamander's hind legs grow more slowly than its front legs. Lungless salamanders have only two limbs.
Most salamanders have defined, fleshy toes for digging and walking. Newts, on the other hand, have fully webbed feet for swimming. However, some species, like the paddle-tail newts, have fully webbed feet with short toes.
7. Reproductive behaviors
Salamanders and newts exhibit different reproductive behaviors. Many female salamanders lay eggs, but two species give birth to live offspring. These species are the alpine salamander and the fire salamander. However, let’s discuss the reproductive behaviors of three different salamander and newt species.
The first species is the tiger salamander. It migrates to breeding ponds in late winter or early spring. The males usually get to the breeding grounds before their female counterparts because they live closer. To mate, they perform a series of nudging.
The male deposits the sperm into the female salamander’s cloaca, and she lays the eggs 24 to 48 hours later. She usually lays the eggs at night, attaching them to twigs, grass stems, and leaves. A female tiger salamander can lay up to 100 eggs, and they hatch 28 days later.
Newt species also exhibit the same behaviors during the breeding season. They travel to breeding sites. However, the distance is not as great as the salamanders’. Newts wrap their eggs carefully in a folded leaf of submerged macrophyte.
The red-spotted newt can produce up to 200 eggs per clutch, while the California newt lays up to 30 eggs per clutch. The eggs of red-spotted newts take up to 35 days before hatching, while California newts take 14 to 21 days.
8. Lifecycle/Lifespan
Newts spend only one-third of their lives in water, usually between February and July. They spend most of their time during spring and summer laying under stones, wood, and thick patches of vegetation.
Aquatic adults lay fertilized eggs, and newts start their lives at the larval stage. Newt larvae grow feathery gills and their front legs before their hind legs. At ten weeks old, they become efts and can breathe through their nose.
We call them efts because they are at the juvenile terrestrial stage. They start living on land at this stage until it is time to breed. They return to the water to mate and repeat the process all over. Newts can live for 17 years, sometimes 20 years.
Salamanders have lifecycle processes that are almost similar to newts. Salamanders hatch eggs in the water and reach the larval stage underwater. Most salamanders are aquatic. So they don't experience a juvenile land phase. Instead, few species reach sexual maturity in their larval forms.
As larvae, salamanders grow external gills and teeth. But they don't develop eyelids. Some salamanders live long. For instance, the brightly colored salamanders live up to 30 years.
Environmental Threats
Newts and salamanders are sensitive to their environment before they have skin that absorbs moisture content. They are highly affected by environmental pollution, habitat destruction, and fungal infections. Human activities are a threat to their existence.
Also, most salamanders are prey to several species of mammals, birds, and reptiles, especially at the beginning of their life cycle. Salamanders have neutral-colored skin, while other salamander species have bright skin.
Those with neutral colors can easily blend into the environment and mimic underwater plants, while those with bright colors have poisonous skin. All species of newts in western North America secrete tetrodotoxin from their poison glands to protect themselves.
As a means of protection, salamanders can regenerate missing limbs. There are several research studies on the developmental biology of the unique salamander. However, most salamanders do not have the same regenerative ability1.
Conclusion: Newts vs. Salamanders
Newts and salamanders are two unique species that are so similar they’ve caused countless confusion. Now, you can tell the difference between a newt and a salamander. Not all species of salamander are newts.
Pin Me:
1 | Gomez, C. M. A., & Echeverri , K. (2021). Salamanders: The Molecular Basis of Tissue Regeneration and Its Relevance to Human Disease. PubMed Central (PMC). |
2 | Vitt, L. J., & Caldwell, J. P. (2009). Salamanders. Elsevier eBooks. |