Reptiles and Amphibians of the Santa Cruz Island Reserve, California
Coluber constrictor is a species of nonvenomous, colubrid snake, endemic to North America and Central America. Eleven subspecies, including the nominotypical subspecies, are recognized, which as a group are commonly referred to as the eastern racers.
Hypsiglena torquata, commonly known as the night snake, is a species of rear-fanged, colubrid. It is found throughout the southwestern and western United States, as well as in Mexico and British Columbia, Canada. The number of subspecies varies depending on the source, but it is generally accepted that there are 17.