Common names: Sonoran Desert sidewinder, Sonoran sidewinder.

Crotalus cerastes cercobombus is a venomous

Venomous snake

"Poisonous snake" redirects here. For true poisonous snakes, see Rhabdophis.Venomous snakes are snakes which have venom glands and specialized teeth for the injection of venom...

 pitviper

Crotalinae

The Crotalinae, commonly known as "pit vipers" or crotaline snakes, are a subfamily of venomous vipers found in Asia and the Americas. They are distinguished by the presence of a heat-sensing pit organ located between the eye and the nostril on either side of the head...

 subspecies

Subspecies

Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...

 found in an area that covers much of the eastern part of the Sonoran Desert

Sonoran Desert

The Sonoran Desert is a North American desert which straddles part of the United States-Mexico border and covers large parts of the U.S. states of Arizona and California and the northwest Mexican states of Sonora, Baja California, and Baja California Sur. It is one of the largest and hottest...

 in the southwestern United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 and northwestern Mexico

Mexico

The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

. The subspecific epithet means buzzertail.

Description

This form has the following distinguishing characteristics: the proximal rattle-matrix lobe is black in adult specimens, the ventral scales

Ventral scales

In snakes, the ventral scales are the enlarged and transversely elongated scales that extend down the underside of the body from the neck to the anal scale. When counting them, the first is the anteriormost ventral scale that contacts the paraventral row of dorsal scales on either side...

 number 132-144/138-148 in males/females, the subcaudals number 18-24/14-19 in males/females, and there are usually less than 21 rows of midbody dorsal scales.

Geographic range

Found in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 from Yuma

Yuma County, Arizona

-2010:Whereas according to the 2010 U.S. Census Bureau:*70.4% White*2.0% Black*1.6% Native American*1.2% Asian*0.2% Native Hawaiian or Pacific Islander*3.8% Two or more races*20.8% Other races*59.7% Hispanic or Latino -2000:...

, Maricopa

Maricopa County, Arizona

-2010:Whereas according to the 2010 U.S. Census Bureau:*73.0% White*5.0% Black*2.1% Native American*3.5% Asian*0.2% Native Hawaiian or Pacific Islander*3.5% Two or more races*12.7% Other races*29.6% Hispanic or Latino -2000:...

, Pima

Pima County, Arizona

-2010:Whereas according to the 2010 U.S. Census Bureau:*74.3% White*3.5% Black*3.3% Native American*2.6% Asian*0.2% Native Hawaiian or Pacific Islander*3.7% Two or more races*12.4% Other races*34.6% Hispanic or Latino -2000:...

 and Pinal

Pinal County, Arizona

-2010:Whereas according to the 2010 U.S. Census Bureau:*72.4% White*4.6% Black*5.6% Native American*1.7% Asian*0.4% Native Hawaiian or Pacific Islander*3.8% Two or more races*11.5% Other races*28.5% Hispanic or Latino -2000:...

 counties in Arizona

Arizona

Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...

, southward into Sonora

Sonora

Sonora officially Estado Libre y Soberano de Sonora is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided into 72 municipalities; the capital city is Hermosillo....

, Mexico

Mexico

The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

. The type locality given is "near Gila Bend, Maricopa County, Arizona" (USA).

Campbell and Lamar (2004) describe its range as the desert regions of south-central Arizona and parts of western Sonora, exclusive of the panhandle region in the west, but including Tiburon Island

Tiburón Island

Tiburón Island is both the largest island in the Gulf of California and the largest island in Mexico, with an area of . It was made a nature reserve in 1963 by President Adolfo López Mateos. Tiburón is Spanish for shark. The etymology of the Seri name is unknown...

 in the Gulf of Mexico

Gulf of Mexico

The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...

.

Taxonomy

This subspecies was established by J.M. Savage and F.S. Cliff, based on information that had previously been published by Stanford, Klauber

Laurence Monroe Klauber

Laurence M. Klauber , was an American herpetologist, and was considered to be the foremost authority on rattlesnakes...

 and Hensley. They described their new form, C. c. cercobombus, as occupying the eastern half of the range for C. c. laterorepens

Crotalus cerastes laterorepens

Crotalus cerastes laterorepens is a venomous pitviper subspecies found in an area that centers around the Colorado Desert in the southwestern United States and northwestern Mexico.-Description:...

as defined by Klauber.