Helioptile is a yellow reptile Pokémon, who has blue eyes and long ears. A shiny Helioptile has a red body.
Helioptile absorbs solar rays to generate electricity. It also charges itself in the sun in such a way it doesn't need to eat. Also, when it is attacking, it opens the "ear-like" structures on its head.
Helioptile evolves into Heliolisk by the use of a Sun Stone. This is odd, as Helioptile and Heliolisk are not Grass-types, but Electric-Normal-types, which a Thunderstone would be a proper method that was not used.