The species belong to the genus Brookesia, also known as leaf chameleons, and adults of the smallest species are just over an inch from nose to tail, researchers writing in the journal PLoS One said.
Brookesia species tend to live within a very small area and the smallest of the newly found species -- Brookesia micra -- was found only on one remote islet in the protected Nosy Hara archipelago off the northern tip of Madagascar.
Miniaturization of species is often found in island populations, researchers said. Known as island dwarfism, it may be the result of limited resources and pressure to reproduce faster.
"The extreme miniaturization of these dwarf reptiles might be accompanied by numerous specializations of the body plan, and this constitutes a promising field for future research," herpetologist Frank Glaw, lead author of the study, said.
"But most urgent is to focus conservation efforts on these and other microendemic species in Madagascar which are heavily threatened by deforestation."