Amphibians
Surinam Toad
Pipa pipa · also called star-fingered toad, pipa toad
The Surinam toad is one of the strangest amphibians alive — a living leaf that lies flat on the bottom of Amazonian pools, feels for its food with star-tipped fingers, and raises its young inside the skin of its own back.
Overview
Surinam toads live in the slow, silty, oxygen-poor waters of the Amazon basin and the Guianas: forest pools, flooded woodland, oxbow lakes, ditches, and swamps. They are almost entirely aquatic, coming to the surface only to breathe and rarely if ever leaving the water as adults. Their whole design is built around staying invisible on a muddy bottom.
A body built for ambush
The Surinam toad is dramatically flattened, roughly triangular, and coloured in dull browns and greys, so it resembles a waterlogged dead leaf. The eyes are minute and lidless, sitting on top of the head. The hind feet are large and fully webbed for swimming; the slender front fingers end in small star-shaped sensory lobes that the toad uses to detect the movement and touch of prey in water too murky to see through.
Because it belongs to the tongueless frog family (Pipidae), it cannot flick out a tongue to feed. Instead it strikes forward and rapidly expands its mouth and throat, sucking prey inside on an inrush of water, and stuffs larger items in with its hands.
The remarkable reproduction
Surinam toad breeding is unlike that of any other frog. A pair performs a series of underwater somersaults, and as they turn, the female releases eggs that the male fertilises and presses onto her back. Over the next day her back skin swells and grows over each egg, enclosing 60 to 100 of them in individual pockets, so the female appears to have a honeycombed hide.
The embryos develop entirely within these chambers — there is no free-swimming tadpole stage. After three to four months, fully formed miniature toads push their way out through the skin and swim off to live independently, and the mother sloughs the used layer of skin.
Status
The Surinam toad is listed as Least Concern, is widespread across northern South America, and faces no major threats at the species level, though it is collected to a small extent for the aquarium trade and is sensitive, like all amphibians, to water pollution, habitat drainage, and disease. Its bizarre appearance and reproduction have made it a frequent — if often deliberately disturbing — subject of viral wildlife content.
Surinam Toad: common questions
How does the Surinam toad give birth from its back?
During an underwater mating "somersault," the male presses fertilised eggs onto the female's back. Her skin then swells up and grows over each egg, sealing it into its own small chamber, so the back becomes a honeycomb of embedded eggs. There is no tadpole stage — the young develop completely inside these pockets, and after three to four months tiny, fully formed toadlets break through the skin and swim away. The mother then sheds the spent layer of back skin.
Why does the Surinam toad look so strange and flat?
It is a fully aquatic frog adapted to lying still and unseen on the bottom of turbid tropical waters. The flattened, angular body and mottled brown colour make it look exactly like a dead leaf or a piece of debris, so both predators and prey overlook it. Its eyes are tiny and set on top of the head, and it has no eyelids.
How does it catch food without a tongue?
Surinam toads belong to the "tongueless frogs" family. Instead of flicking a tongue, the toad detects prey with the sensitive star-shaped tips of its long front fingers, then lunges and suddenly opens its mouth and expands its throat, creating a suction that pulls the prey straight in, sometimes helped by a scooping motion of the hands. It swallows fish, worms, and other animals whole.
Does the Surinam toad's "hole-filled back" video actually show a real animal?
Yes. Widely shared images and videos of a lumpy amphibian back releasing dozens of tiny toads — often posted to unsettle people with "trypophobia," a discomfort with clustered holes — are genuine footage of Pipa pipa giving birth. The reproductive method is real and unique among frogs to this genus.