7 species have Flame Body as a hidden ability, 14 as a normal one

Effect, in PokéAPI's words

“Has a 30% chance of burning attacking Pokémon on contact.”

As a hidden ability

Species	Slot	Note
Ponyta	Hidden	Since Generation V
Rapidash	Hidden	Since Generation V
Moltres	Hidden	Since Generation V
Heatran	Hidden	Since Generation V
Sizzlipede	Hidden
Centiskorch	Hidden
Charcadet	Hidden

As a normal ability

Species	Slot	Note
Magmar	Normal
Slugma	Normal
Magcargo	Normal
Magby	Normal
Magmortar	Normal
Litwick	Normal
Lampent	Normal
Chandelure	Normal
Larvesta	Normal
Volcarona	Normal
Fletchinder	Normal
Talonflame	Normal
Carkol	Normal
Coalossal	Normal

Elsewhere in PokéAPI

2 more holders without a page here

Alternate forms and other species that PokéAPI lists with Flame Body.

Coalossal Gmax, Centiskorch Gmax (hidden)