Mexican Patchnose Snake, Salvadora mexicana

Mexican Patchnose Snake, Salvadora mexicana. Snake photographed in in the greater Zihuantanejo area, Guerrero, March 2019. Photograph courtesy of Ron Woheau, Zihuantanejo.

The Mexican Patchnose Snake, Salvadora mexicana, is a member of the Colubridae Family of North American Racers, Coachwhips, and Whipsnakes. They are known in Mexico as Cuijera, Culebra Chata del Pacífico, Culebra Manguera, Culebra Nariz de Parche Mexicana, and Culebra Parchada Mexicana. The Colubridae Family comprises two-thirds of the world’s snake population with one thousand seven hundred sixty species placed in two hundred forty-nine genera. Many Colubrids are classified as venomous but very few are considered to be dangerous to humans. There are six species in the Salvadora Genus.

The Mexican Patchnose Snake is a moderately-sized, terrestrail snake that reaches a maximum of 1.5 m (5 feet 11 inches) in length with a tail length of 31 to 41% of total length. The males are larger than the females. They are slender in stature. They are characterized by an enlarged rostral with free edges that is used to dig in loose soil. They have 17 smooth dorsal scale rows at mid-body and 13 posteriorly with a divided anal plate and two or more anterior temporals. The back of the head is dark with a pale longitudinal patch at the center. The first third of the body has transverse patches that transition to transverse bars on the neck. The rear of the body has a pale line flanked by two dark lines and two dark lines. Ventrally they are white to yellowish in color.

The Mexican Patchnose Snake is a secretive highly adaptive species that is found in a variety of habitats including tropical dry forest, semi-deciduous forest, and cultivated land. They are diurnal and feed primarily on amphibians, insects and lizards.

The Mexican Patchnose Snake is ENDEMIC to Mexico being found on the Pacific slope from Sinaloa south to Oaxaca and as far north as Zacatecas in the central highlands.

Due to its facial markings the Mexican Patchnose Snake is a straightforward identification that can be confused with the Chicken Snake, Spilotes pullatus (widely spaced narrow vertical black lines on the cheeks) and the Striped Road Guarder, Conophis vittatus (lacks vertical banding on the cheeks).

From a Conservation perspective the Mexican Patchnose Snake is currently considered to be of Least Concern with stable widely distributed populations without major threats. They play an important ecological role as both predators and prey. They are prone to loss of habitat due to human development.

Synonym: Zamenis mexicanus