Brachycephalus species are very small frogs , up to 1.8 cm ( 0.71 in ) in length ( mostly around 1 cm or 0.39 in ) , and include the smallest frog in the Southern Hemisphere , Izecksohn 's toad ( Brachycephalus didactylus ) .
They include the smallest frog in the southern hemisphere , Izecksohn 's Toad ( Brachycephalus didactylus ) .