Tadpole

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.

Another example is the tadpoles of the New Mexico spadefoot toad (Spea multiplicata) which will develop a carnivorous diet along with a broader head, larger jaw muscles, and a shorter gut if food is scarce, allowing them to consume fairy shrimp and their smaller herbivorous siblings.

[4] A few genera such as Pipidae and Microhylidae have species whose tadpoles are filter feeders that swim through the water column feeding on plankton.

Lungs develop around the time as the legs start growing, and tadpoles at this stage will often swim to the surface and gulp air.

The tadpoles of Micrixalus herrei are adapted to a fossorial lifestyle, with a muscular body and tail, eyes covered by a layer of skin, and reduced pigment.

Female marsupial frogs (Hemiphractidae) will carry eggs on her back for various amounts of time, with it going as far as letting the tadpoles develop into tiny froglets in a pouch.

[12] Male midwife toads (Alytes) will carry eggs between their legs to protect them from predators, eventually releasing them into a body of water when they are ready to hatch.

[13] Despite their soft-bodied nature and lack of mineralised hard parts, fossil tadpoles (around 10 cm in length) have been recovered from Upper Miocene strata.

Other parts of the tadpoles' bodies exist as organic remains and bacterial biofilms, with sedimentary detritus present in the gut.

Tadpoles of the megophryid frog Oreolalax rhodostigmatus are particularly large, more than 10 cm (3.9 in) in length,[6] and are collected for human consumption in China.