| Canidae, Eucyon, Mammal, Mesocyon, Hesperocyon|
Leptocyon (Greek: slender dog) is a small extinct genus of canid endemic to North America during the Oligocene through Miocene living from 24.8—10.3 million years ago, existing for about 25.8-10.3 million years.
Leptocyon was a small-bodied, fox-like animal with a slender jaw.
Leptocyon was named by Matthew (1918). It was synonymized subjectively with Vulpes by Gregory (1942); it was revalidated by Webb (1969), Carroll (1988), and Munthe (1998). It was assigned to the Canidae by Matthew (1918), Webb (1969), Carroll (1988), and Munthe (1998).
Two specimens were examined by Legendre and Roth. Estimated body mass of these two was 3.26 kg (7.2 lb)