Brachycephalus pernix is a small and brightly coloured species of frog in the family Brachycephalidae. It is endemic to Paraná in southeastern Brazil and only known from a single location at an altitude of 1,135–1,405 m (3,724–4,610 ft) on Serra da Baitaca in Serra da Baitaca State Park. This diurnal species lives among leaf litter on the floor of Atlantic rainforest.
Its conservation status was last reviewed by the IUCN in 2004 where regarded as data deficient (insufficient information for rating it), but an independent review in 2019 that used IUCN's criteria recommended that B. pernix should be recognised as vulnerable.
