Triadobatrachus ('triple-frog') is an extinct genus of frog-like
amphibian, including only one known species, Triadobatrachus
massinoti. It is the oldest frog known to science, and an
excellent example of a transitional fossil. It lived during the
Early Triassic about 250 million years ago, in what is now
Madagascar.Triadobatrachus was 10 centimetres (3.9 in) long, and
still retained many primitive characteristics, such as
possessing fourteen vertebrae, where modern frogs have only four
to nine. Six of these vertebrae formed a short tail, which the
animal retained as an adult. It probably swam by kicking its
hind legs, although it could not jump, as most modern frogs can.
Its skull resembled that of modern frogs, consisting of a
latticework of thin bones separated by large openings. As
evidenced by its large ear openings, Triadobatrachus possessed
good hearing.This creature, or a cousin, evolved eventually into
modern frogs, the earliest example of which is Sanyanlichan,
millions of years later in the late Ju