Frogs are amphibians with large eyes and rough skin belonging to the genus Rana, of the family Ranidae. There are various species of frogs distributed on Planet Earth and it is estimated that practically a third of all of them are in vulnerable state or in Danger of extinction
In this article on our site we will talk about the different types of frogs that exist including the most popular species. But in addition, we will also mention the types of frogs in Spain or those that are poisonous. Read on to discover them!
Characteristics of frogs
Frogs are a genus of amphibians of relatively small size that range between scarce 8 millimeters and 30 centimeters They are part of the group of the anurans, or what is the same, batrachians without tails. However, despite not having this limb in adulthood, they do have very long and developed hind legs that allow them to make great jumps and move with agility.
These little animals not only defend themselves well on land, but are also animals adapted to living in freshwater environments and even in trees or underground. Although we can find them in almost any corner of the planet, the greatest diversity of frog species is found in tropical humid forests In any case, they are one of the animals that best they adapt to the environment in which they live, with the exception of the polar areas, where no species of frogs have been described due to their intolerance to cold.
Frogs in general are carnivorous animals, although there are also some types of frogs omnivorous or frugivorous They normally feed on aquatic and terrestrial invertebrates, such as insects, arachnids and crustaceans, but also small vertebrates, such as lizards or mice. When prey is close, the frog watches it until it is ready and close enough to stick out its tongue and catch it. The prey then sticks and is quickly devoured.
On the other hand, these amphibians are oviparous animals, that is, they lay eggs and normally deposit them in the water. After hatching, the aquatic larvae or tadpoles, characteristic for having a tail and gills, survive in the water until completing the metamorphosis that turns them into adult frogs.
Finally, we must highlight two of the peculiarities by which people best know these animals. First of all, frogs are famous for their vocalizationsThey have a wide range of sounds, especially varied in the breeding season. However, it is appropriate to comment that this famous "cruac" is, in general, more characteristic of males.
Secondly, these amphibians stand out for their "shiny" skin. What really happens is that these beings are semi-permeable, which makes them susceptible to dehydration. That is why we usually appreciate these funny little animals on the shores of humid places.
Difference between frog and toad
Frog and toad are often confused due to the numerous characteristics they share. However, there is a clear difference between the two: frogs have smooth or almost smooth skin and a slender or athletic body, whileToads have rougher skin or with warts and a broader body. Likewise, the concept of frog refers to the genus Rana. Instead, toads are amphibians that belong to the genus Bufo.
What kinds of frogs are there?
Within the order of the anurans (Anura) and the family of the ranids(Ranidae) we found 24 genera that are currently recognized. One of them is the genus rana (Frog), considered the "true frogs" a name that allows to differentiate the species of this genus from others that contain the term "frog" in their common name and which do not belong to the genus frog. Thus, it is currently considered that there are 49 species of true frogs in the world.
Types of True Frogs
Below we show you five species of true frogs with their names and images:
1. Wood Frog (Rana arvalis)
The country frog is endemic to Europe and Asia, adapting to all types of habitats, such as tundra, forests or steppe. It is reddish-brown in color and stands out for being camouflaged especially well among the vegetation. It measures between 5, 5 and 7 cm. in length and since 2008 it has been in a situation of minor concern according to the IUCN, the red list of species.
two. Northern Red-legged Frog (Rana aurora)
For its part, the northern red-legged frog, is one of the types of frogs native to North America, ranging from Canada to the United States. We can find this species in calm waters of ponds, streams or ponds. It can reach 8 cm. and stands out for having a brown or reddish smooth skin, accompanied by small black spots. It is also a species considered to be of least concern.
3. Iberian frog or long-legged frog (Rana iberica)
The Legged Frog is a species endemic to the Iberian Peninsula, which includes Spain and Portugal. Inhabits swamps, rivers and mountain streams. This little frog, about 7 cm. it is threatened by the loss of its habitat and will soon be listed as vulnerable if its population continues to decline.
4. Grass Frog (Rana temporaria)
The grass frog, also known as the common frog, is endemic to Europe and Asia. It spends practically its entire life on land, however, it can dive into the water to reproduce or hide from possible predators. It is of robust appearance, measuring between 6 and 9 cm., and is brownish in color. It is a species considered to be of least concern.
5. Mountain Yellow-legged Frog (Rana mucosa)
We end the types of frogs in the genus Rana with the mountain yellow-legged frog, a species endemic to California, United States, which measures between 4 and 9 cm. about. It is usually yellowish in color with black and brown markings, but can also have olive tones. This species is in danger of extinction and, as a curiosity, it emits a defensive odor similar to garlic.
Untrue frog types
Although the species that we will mention below do not belong to the genus Rana, they are worth knowing about because of their enormous popularity:
1. Goliath Frog (Conraua goliath)
The Goliath frog, as its name implies, is huge, reaching up to 30 centimeters, which makes it the largest in the world. Still, its size depends largely on its diet and the location of the species. Other typical characteristics of the Goliath frog are its olive green color with varied and patterned shapes that allow it to blend in with its surroundings and its lack of vocalization. Thus, despite its good hearing, we will not hear this little frog croaking.
Although this species has become popular as a pet, we must know that its maintenance, especially complicated, and the loss of habitat are causing a significant decline in its population. For all these reasons, it is currently in danger of extinction
two. Glass frog (Hyalinobatrachium fleischmanni)
One of the most particular characteristics of this frog endemic to America is that its skin is transparent, so we can observe its organs inside. In fact, if we look closely, we can even see its little heart beating and pumping blood. This transparency brings a very positive associated advantage for the species, in certain sciences such as medicine, a great variety of reactions can be studied and observed without dissecting the animal.
Despite their main characteristic, these frogs have a greenish color and are very small, usually between 3 and 4 centimetersin adulthood. They are also arboreal amphibians, so they live high up in the trees in forests of the Andes, Central America, and South America. There they feed on small insects during their nocturnal habits. It is a species that is currently listed as a least concern
3. Flying Frog (Rhacophorus nigropalmatus)
Yes, this frog seems to fly thanks to its long fingers connected by a membrane that allows it to move through the air as if it had a parachute. This "flight" is carried out instinctively and gives it great advantages in nature, such as moving from one tree to another just by gliding. In addition to this, as you can already guess, the flying frog is also arboreal and native to the Philippine Islands It is also considered a minor concern.
4. South African black frog (Breviceps fuscus)
Apart from being black, this strange frog is about 4 to 5 centimeters is plump, with tubercles and has a serious face. Originally from South Africa, the black frog lives mainly in temperate forests, although its habitat and, consequently, the species is considered a least concern Another curiosity about the species is that it can inflate its body if the occasion requires it, such as to avoid being eaten by predators.
5. Mossy Frog (Theloderma corticale)
What best defines this frog, also known as "moss frog" is its amazing ability to camouflage, which makes it almost invaluable in its natural habitat, as intropical and subtropical forests of Vietnam. This enormous advantage allows it to go unnoticed both in front of its prey and its predators. Its population is declining and, once again, we note that it is one of the types of frogs that are considered a least concern
6. Red-eyed Tree Frog (Agalychnis callidryas)
The red-eyed tree frog is especially striking due to the colors that adorn its anatomy: green, blue, yellow, orange and deep blue, all accompanied by its bulging eyes. However, despite these characteristics, this frog is not poisonous. It is an animal considered as minor concern. It is a nocturnal and solitary animal that is usually found in the lowlands or high in trees or bushes of the tropical forests found in southern Mexico, Central America and northern South America.
Types of poison dart frogs
Although the skins of frogs generally vary between green, brown and gray colors, there are certain species that present more striking colors such as red, yellow, black and blue to alert their predators of the toxicity that they they present. Next, we present some species of poisonous frogs. You better not kiss them!
1. Golden Frog (Phyllobates terribilis)
This amphibian with such a striking and attractive color and that may seem harmless is considered the most dangerous and toxic vertebrate on the planet Poison of the skin of a single specimen is enough to kill up to 10 adults. It is in danger of extinction
This species is diurnal, measures around 5 centimeters and can be found on the Pacific coast and the Amazon in Colombia. As a carnivorous species, the golden frog feeds on insects such as flies, ants, crickets, beetles, and termites. Finally, although its characteristic color is yellow, depending on the specimen the colors can vary between yellow, orange or mint green.
two. Blue Arrow Frog (Dendrobates azureus)
The blue arrow frog is a color rarely seen in the animal kingdom. It is another of the poisonous frog specimens. However, such a bright and showy color, as in the rest of the cases, serves to alert predators of its high toxicity. It lives in tropical forests of Brazil and southern Suriname, measures about 3-4 cm. and it is a diurnal species.
Regarding its diet, the blue arrow frog follows a carnivorous diet based mainly on insects. Finally, it should be noted that it is a kind of aggressive and territorial character. It is considered a minor concern.
3. Harlequin Frog (Atelopus varius)
The harlequin frog has a highly powerful poison, as its colors indicate, which vary between yellow, green, red and orange. Many frogs in the family also have spots or stripes. Diurnal like its other two companions on the list, the harlequin frog is endemic to Costa Rica and western Panama, and can be seen in lowlands and humid forests of Mountain. This species is critically endangered due to deforestation of its habitat and invasive species that threaten its survival.
Types of frogs in Spain
The four species of true frogs that inhabit Spain are:
- Iberian Frog
- Pyrenean Frog
- Dalmatian frog
- Temporary frog
But also, within the family Ranidae, we find the following types of frogs:
- Pelophylax perezi
- Pelophylax saharicus
- Pelophylax kl. graphi
- Lithobates catesbeianus
