Nidoran♂ is a small, rabbit-based Pokémon with large ears, whiskers and front teeth. They are covered with spines, primarily on their back, which can release potent poisons if Nidoran♂ is threatened. Nidoran♂ have a larger forehead horn than their female counterparts, Nidoran♀. It has darker spots all over its body.
Its large horns can secrete a powerful venom, unlike its female counterpart, the size of the horns is indicative of the strength of the venom. It also has unique muscles around its ears, which permit them to be moved in any direction.
Nidoran♂ with its counterpart, Nidoran♀, were featured in the episode Wherefore Art Thou, Pokémon? . A young boy named Ralph owned a Nidoran♂ which evolved into a Nidorino after kissing his friend Emily's Nidoran♀.