Common Surinam toad | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Amphibia |
Order: | Anura |
Family: | Pipidae |
Genus: | Pipa |
Species: | P. pipa |
Binomial name | |
Pipa pipa | |
Surinam toad range. [1] | |
Synonyms | |
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The common Surinam toad, the Suriname toad, or star-fingered toad (Pipa pipa), is a fully-aquatic species of frog, in the family Pipidae, with a widespread range across much of tropical South America and the island of Trinidad. [2] The females of this species are well-known for "incubating" their eggs on their backs, in honeycomb-like depressions directly within the skin, releasing fully-formed froglets after a period of 4–5 months. Pipa pipa is an ambush predator, lying in-wait underwater for prey to inevitably wander too close, swiftly inhaling the unsuspecting creature using suction feeding. Additionally, the Surinam toad's rather flat body shape, combined with rather dark, dull coloration, serves as effective camouflage in the murky waters they inhabit, perfectly mimicking a dead leaf or piece of rotting wood as they await their next meal.
P. pipa is a strictly aquatic frog and the largest member of its genus. The species has an exceptionally depressed body, almost entirely flat and with a broad, flat, triangular head. It is without a tongue. [3] The body is similar in appearance to a mottled brown leaf. The feet are broadly webbed with the front toes having small, star-like appendages. Males can grow up to 154 mm long, whereas females can reach up to 171 mm. Females can be distinguished not only by their length but also by their ring-shaped cloacas, visible when they are ready to breed. [4] The skin color is mostly light brown with some darker spots on the back, providing good camouflage [4] [5] Nostrils are terminal, eyes very small, and the tympanum is missing. The limbs are in a laterally sprawled position in the plane of the body, and the fingertips are modified into four small lobes. [6] Absence of a tongue prevents the species from capturing prey with that organ like most other frogs, and instead suction capture is used. [7]
The skull is hyperossified and the cranial and postcranial bones are heavily modified compared to other anurans. While the eyes are relatively small and narrow, the species has a lateral line system and neuromast organs which are assumed to help it locate prey and predators. [3]
The Surinam toad lacks dermal antimicrobial peptides that may inhibit disease agents such as chytridiomycosis and Ranavirus, which could make it slightly more susceptible to disease. [8]
The Surinam toad, despite its common name, is actually native to several South American countries; as well as Suriname, it is known from Brazil (primarily the states of Acre, Amazonas, Mato Grosso, Pará and Rondônia), Bolivia, Colombia, Ecuador, French Guiana, Guyana, and Venezuela, in tropical rainforest regions to the east of the Andes. [9] Additionally, a small population may be found in the southwestern corner of the island of Trinidad, just north of Venezuela across the Columbus Channel. [2] Pipa pipa has the largest geographic distribution within its genus. [10] The Surinam toad inhabits warm, acidic, murky and slow-moving to still waterways, including streams, backwaters, ponds and seasonal pools after localized flooding; these rich waters often have a low pH due to a high concentration of organic matter and tannins. [10]
It is so strongly adapted for an aquatic lifestyle that on land it is helpless and scarcely able to move. [11]
The species is an omnivorous ambush hunter. Its diet consists mostly of invertebrates, such as worms, insects, crustaceans and small fish. [4] [12] [13] Field caught Pipa pipa have been found with erythrinid fish species, other small Pipa pipa, catfish, arthropods and amphibian skin in their stomachs. [3] One study found that Cyclopoida made up 67%, Diptera larvae 7.3%, and Heteroptera 6.3% of prey. The skin fragments that were found in their stomach are an indication that these frogs commit cannibalism or eat their own skin which is common among amphibians. Based on these results, P. pipa is an ambush predator that will opportunistically eat anything that falls into the water or that it may encounter when occasionally foraging on land. [14]
P. pipa employs a unique inertial suction feeding mechanism. The Surinam toad catches prey by entraining large volumes of water for ingestion and by limiting fish escape with its fingers. It uses bidirectional suction, a process the frog initiates by depressing its hyoid and retracting its clavicle.
The amount of entrained water the frog can ingest is related to its ability to actively increase its body volume. The frog's buccopharyngeal cavity (the cavity connecting the mouth and the pharynx) is very distensible and can expand substantially. It uses its entire trunk to rapidly enlarge the cavity, which expands into the lower end of the trunk. Its visceral organs—the hyoid and larynx, heart, lungs, liver, esophagus, and stomach—are arranged so as to be capable of moving rearward by up to a third of the length of the body; this gives additional space for expansion of the buccopharyngeal cavity. Laboratory observations estimate P. pipa can achieve an increase in trunk volume of 1.5 times the resting volume. The rapid (in c. 12–24 milliseconds) expansion of the buccopharyngeal cavity results in negative pressure; this creates the suction which, in turn, entrains the water containing the prey. The fish are effectively siphoned into the expanded buccopharyngeal cavity, where it remains for a time, located centrally in the trunk of the frog, not the stomach. The siphoned water is released through the frog's partially open mouth, as its internal pressure returns to normal, while its forelimbs remain raised close to the mouth, guarding against the possibility of prey escape. [3]
The species may be the only tetrapod vertebrate that can enlarge its entire trunk during suction feeding. Additionally, it has been found that P. pipa can modulate the timing of most elements of its prey capture process. For instance, it can asymmetrically or asynchronously move its jaw during the capture and manipulation of its prey. [3]
The forelimbs are used to "scoop" the prey into the mouth. Prior to capture of its prey, the forelimbs are held in a forward-flexed position so that each hand is positioned in front of the head. During prey capture, the forelimbs are extended and drawn towards the mouth. If the prey item is encountered during this movement, it is grabbed and pushed into the mouth. Otherwise it is sucked into the mouth without any use of the limbs. These frogs have a high degree of dexterity compared to other pipid species. [3]
The mating period of these frogs is during the fall and winter seasons. These frogs call usually during the morning and mid-afternoon hours. [15] Males of this species do not attract females with croaks, instead producing a sharp clicking sound by snapping the hyoid bone in their throats. [16] The clicking sound resembles metallic noises. The average rate of these clicks is four clicks per second, consisting of blocks of 10 to 20 seconds per period. [15] Thereafter, the male will grab the front legs of the female in amplexus, causing the cloaca and the skin of the female to swell. [17] The partners rise from the floor while in amplexus and flip through the water in arcs. The couple will swim around in the water until they have to swim to the surface to breathe. Afterwards, they will swim back down to the bottom of the water. There the male will lay on his back, with the female on top of him on her stomach. [18] During the amplexus, the female's back is gradually swelled to a puffy condition. The male and female cloacae are brought close together, and many eggs are transferred anteriorly to the female's swollen dorsal epidermis.
The eggs, each around 6.5 mm in diameter, then become implanted into the female's dorsal epidermis. During the first day the eggs on the female's back will sink into the skin and by evening will be set into the back of the female. Two days later, the yolks of most of the eggs are beneath the skin level and only parts of the jelly and outer membranes of the eggs are visible on the backs above. The coverings over the eggs will remain in the wild until the brood emerges. [15] The embryos develop through to the tadpole stage inside these pockets but do not emerge as tadpoles, instead remaining in their chambers until complete development to toadlet stage. The young toads grow a tail during their growth, but these will only be temporary because they will need the tail for inhaling oxygen. After 12 to 20 weeks, the young toads will hatch as small toads, looking identical to their parents. It takes a while for them to grow bigger since they are only 25 mm long when they are born. Once they have emerged from their mother's back, the toads begin a largely solitary life. After giving birth to the new toads, the mother slowly sheds the thin layer of skin used for birth and can begin the cycle again. [4] [6]
When two males encounter each other during the mating season, there is a possibility that the two males will fight. The toads nearly press their snout to the chest or throat of the other male. During the conflict, both males make single clicks to each other, which resembles the sound that they normally use during breeding. If the toads have eye contact, they make a rapid series of these clicks. This process shows no visible movement of the vocal system. After some time, they will return to swimming, but will never lose contact with one another. One toad swims very closely above the other, touching his rival with only the front limbs. The fight between males may be long-lasting. Eventually, one of the males bites the other male and this is supposed to be the end of their encounter, although they do not always give up the fight. It may happen that the male that loses the battle does not give up and disturbs the breeding pair itself, even during reproduction. [15]
Although the species is classified as Least Concern by the IUCN, it is subject to habitat loss and habitat fragmentation caused by agricultural expansions. [1] Due to the deforestation and human encroachment on the Amazon rainforest, the species has been found in regions where it would not normally be encountered, such as terrestrial locations. This highlights the importance of preserving the endangered habitats that these frogs live in. [10] [19]
In the aquarium, the species prefers plants and rocks to hide behind. Low light conditions are required. Because the Surinam toad excretes high amounts of ammonia, water changes have to be frequent. [20]
In a letter to Catherine Clarkson the poet Samuel Taylor Coleridge writes "I envy dear Southey's power of saying one thing at a time in short and close sentences, whereas my thoughts bustle along like a Surinam Toad, with little toads sprouting out of back, side, and belly, vegetating while it crawls". [21]
The Surinam toad is commonly cited as an example of a trypophobia trigger. [22]
Amphibians are ectothermic, anamniotic, four-limbed vertebrate animals that constitute the class Amphibia. In its broadest sense, it is a paraphyletic group encompassing all tetrapods excluding the amniotes. All extant (living) amphibians belong to the monophyletic subclass Lissamphibia, with three living orders: Anura, Urodela (salamanders), and Gymnophiona (caecilians). Evolved to be mostly semiaquatic, amphibians have adapted to inhabit a wide variety of habitats, with most species living in freshwater, wetland or terrestrial ecosystems. Their life cycle typically starts out as aquatic larvae with gills known as tadpoles, but some species have developed behavioural adaptations to bypass this.
A frog is any member of a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura. The oldest fossil "proto-frog" Triadobatrachus is known from the Early Triassic of Madagascar, but molecular clock dating suggests their split from other amphibians may extend further back to the Permian, 265 million years ago. Frogs are widely distributed, ranging from the tropics to subarctic regions, but the greatest concentration of species diversity is in tropical rainforest. Frogs account for around 88% of extant amphibian species. They are also one of the five most diverse vertebrate orders. Warty frog species tend to be called toads, but the distinction between frogs and toads is informal, not from taxonomy or evolutionary history.
The African clawed frog, also known as simply xenopus, African clawed toad, African claw-toed frog or the platanna) is a species of African aquatic frog of the family Pipidae. Its name is derived from the short black claws on its feet. The word Xenopus means 'strange foot' and laevis means 'smooth'.
Amphiuma is a genus of aquatic salamanders from the United States, the only extant genus within the family Amphiumidae. They are colloquially known as amphiumas. They are also known to fishermen as "conger eels" or "Congo snakes", which are zoologically incorrect designations or misnomers, since amphiumas are actually salamanders, and not fish, nor reptiles and are not from Congo. Amphiuma exhibits one of the largest complements of DNA in the living world, around 25 times more than a human.
Amplexus is a type of mating behavior exhibited by some externally fertilizing species in which a male grasps a female with his front legs as part of the mating process, and at the same time or with some time delay, he fertilizes the eggs, as they are released from the female's body. In amphibians, females may be grasped by the head, waist, or armpits, and the type of amplexus is characteristic of some taxonomic groups.
A tadpole or polliwog is the larval stage in the biological life cycle of an amphibian. Most tadpoles are fully aquatic, though some species of amphibians have tadpoles that are terrestrial. Tadpoles have some fish-like features that may not be found in adult amphibians such as a lateral line, gills and swimming tails. As they undergo metamorphosis, they start to develop functional lungs for breathing air, and the diet of tadpoles changes drastically.
The American bullfrog, often simply known as the bullfrog in Canada and the United States, is a large true frog native to eastern North America. It typically inhabits large permanent water bodies such as swamps, ponds, and lakes. Bullfrogs can also be found in manmade habitats such as pools, koi ponds, canals, ditches and culverts. The bullfrog gets its name from the sound the male makes during the breeding season, which sounds similar to a bull bellowing. The bullfrog is large and is commonly eaten throughout its range, especially in the southern United States where they are plentiful.
Egg incubation is the process by which an egg, of oviparous (egg-laying) animals, develops an embryo within the egg, after the egg's formation and ovipositional release. Egg incubation is done under favorable environmental conditions, possibly by brooding and hatching the egg.
Suriname toads are members of the frog genus Pipa, within the family Pipidae. They are native to northern South America and extreme southern Central America (Panama). Like other pipids, these frogs are almost exclusively aquatic.
Agalychnis callidryas, commonly known as the red-eyed tree frog or red-eyed leaf frog, is a species of frog in the subfamily Phyllomedusinae. It is one of the most recognizable frogs. It is native to forests from Central America to north-western South America. This species is known for its bright coloration, namely its vibrant green body with blue and yellow stripes on the side. It has a white underside, brightly red and orange colored feet, and is named after its distinctive bright red eyes. One particular and special feature of the frogs coloration is its exceptional high reflectance in the near-
The Mexican burrowing toad is the single living representative of the family Rhinophrynidae. It is a unique species in its taxonomy and morphology, with special adaptations to assist them in digging burrows where they spend most of their time. These adaptations include a small pointed snout and face, keratinized structures and a lack of webbing on front limbs, and specialized tongue morphology to assist in feeding on ants and termites underground. The body is nearly equal in width and length. It is a dark brown to black color with a red-orange stripe on its back along with splotches of color on its body. The generic name Rhinophrynus means 'nose-toad', from rhino- (ῥῑνο-), the combining form of the Ancient Greek rhis and phrunē.
African dwarf frog is the common name for members of Hymenochirus, a genus of aquatic frog native to parts of Equatorial Africa. They are common in the pet trade and are often mistaken for the African clawed frog, a similar-looking frog in the same family. Their common name is obtained from their place of origin and the claws on their hind legs.
Gastrophryne carolinensis, the eastern narrow-mouthed toad, is a species of microhylid frog. It is a relatively small, toad-like amphibian found in damp, shady habitats. The species is highly fossorial, and feeds primarily on ants. These North American microhylids are distinguished from true toads, and other anurans by their moist, smooth skin, their lack of eardrums or tympana, their distinguishable squat body shape, and the unique fold of skin superior to their eyes. It is found in the United States, from southern Maryland to the Florida Keys, west to Missouri and Texas. While not a true toad, it is so called because it is terrestrial.
Uperodon montanus, also known as Jerdon's narrow-mouthed frog, Jerdon's ramanella, mountain dot frog, mountain globular frog, or Malabar Hill frog, is a species of narrow-mouthed frog endemic to the Western Ghats of India.
Lepidobatrachus laevis, widely known as Budgett's frog, is a species of frog in the family Ceratophryidae, discovered by John Samuel Budgett. It is often kept as a pet. It has acquired a number of popular nicknames, including hippo frog, Freddy Krueger frog, and escuerzo de agua.
Chiasmocleis ventrimaculata, also known as the dotted humming frog, is a species of frog in the family Microhylidae. It is found in Bolivia, Brazil, Colombia, Ecuador, and Peru. Its natural habitats are subtropical or tropical moist lowland forests, swamps, and intermittent freshwater marshes.
The quacking frog, also known as the red-thighed froglet due to its legs tending to be bright red, is a species of frog from the Myobatrachidae family and is in a clad with five other species. The frog is well known for the sound it produces which resembles a quack. It has up to 11 notes and can change the notes in their call. It has larger testes compared to other frogs within the genus and has started to be used in experiments. This frog is found in southwest Australia. It is found in ponds and pools and other moisture filled areas. These frogs engage in polyandry and can result in multiple paternity of its offspring. Additionally, the tadpoles of this species can change the rate they metamorphosize depending on the conditions. The males tend to have larger arm girth and can adopt different mating strategies depending on size. The mating strategy is dependent on male density. The frogs also vary in terms of colour and texture of its skin. The tadpoles are generally golden with transparent tails.
Pipa aspera, the Albina Surinam toad, is a species of frog in the family Pipidae found in French Guiana, Suriname, and possibly Brazil. Its natural habitats are subtropical or tropical moist lowland forests, rivers, freshwater marshes, and intermittent freshwater marshes. The color of this species is a reddish-brown to a brownish-black, noticed on the dorsal part of its body. The weights of females range between 5 and 12 grams, and males between 4 and 7 grams, noting that females are usually significantly larger.
The Sabana Surinam toad(Pipa parva), also known as the dwarf toad, is a species of frog in the family Pipidae. It is found in northwestern Venezuela and northeastern Colombia (Norte de Santander and La Guajira Departments), mainly in the Maracaibo Basin. There is an introduced (and expanding) population in the Lake Valencia Basin in northern Venezuela.
The Ranoidea are a superfamily of frogs in the order Anura. Members of this superfamily are characterised by having the pectoral girdle fused into a single complex unit, having no ribs, and using an axillary grip during amplexus. The larvae have a single spiracle on the left side and complex mouthparts, or in some species, undergo direct development. The taxonomy of these families has been under heavy debate for many years. In recent studies, molecular data has been used to better identify the phylogentic relationships of these frogs, rearranging and introducing new subfamilies to better distinguish between large groups of frogs.