The Brazilian flea toad may be the world’s smallest vertebrate

Males measure about seven millimeters long on average

A tiny brown frog sits just off center on a Brazilian real coin.

The Brazilian flea toad has nabbed the title of world’s smallest known amphibian and smallest known vertebrate. At just 7 millimeters long on average, the frogs are a fraction the size of a 27-millimeter-wide $1 Brazilian real coin.

W.H. Bolaños, I.R. Dias and M. Solé/Zoologica Scripta 2024

A Brazilian flea toad’s head is too tiny to bear its many crowns.