Common names: ground rattlesnake

Rattlesnake

Rattlesnakes are a group of venomous snakes of the genera Crotalus and Sistrurus of the subfamily Crotalinae . There are 32 known species of rattlesnake, with between 65-70 subspecies, all native to the Americas, ranging from southern Alberta and southern British Columbia in Canada to Central...

s, pigmy rattlesnakes, massasaugas.

Sistrurus is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of 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...

 pit vipers found in Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

, the United States

United States

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

 and 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 name is a Latinized form of the Greek

Greek language

Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...

 word for "tail rattler" (Σείστρουρος, Seistrouros) and shares its root with the ancient Egypt

Egypt

Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...

ian musical instrument, the sistrum

Sistrum

A sistrum is a musical instrument of the percussion family, chiefly associated with ancient Iraq and Egypt. It consists of a handle and a U-shaped metal frame, made of brass or bronze and between 76 and 30 cm in width...

, a type of rattle. Three species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 are currently recognized.

Description

Sistrurus species differ from the larger rattlesnakes of the genus Crotalus

Crotalus

Crotalus is a genus of venomous pit vipers found only in the Americas from southern Canada to northern Argentina. The name is derived from the Greek word krotalon, which means "rattle" or "castanet", and refers to the rattle on the end of the tail which makes this group so distinctive...

 in a number of ways. They are smaller in size, but also their scalation

Scale (zoology)

In most biological nomenclature, a scale is a small rigid plate that grows out of an animal's skin to provide protection. In lepidopteran species, scales are plates on the surface of the insect wing, and provide coloration...

 is different: Sistrurus species have nine large head plates (same as Agkistrodon

Agkistrodon

Agkistrodon is a genus of venomous pit vipers found in North America from the United States south to northern Costa Rica. The name is derived from the Greek words ἄγκιστρον 'fishhook' and ὁδοὐς 'tooth', and is likely a reference to the fangs...

), whereas with Crotalus (and almost all other viperids

Viperidae

The Viperidae are a family of venomous snakes found all over the world, except in Antarctica, Australia, Ireland, Madagascar, Hawaii, various other isolated islands, and above the Arctic Circle. All have relatively long, hinged fangs that permit deep penetration and injection of venom. Four...

) the head is mostly covered with a large number of smaller scales. Sistrurus species have a relatively small rattle that produces more of a high-pitched, buzzing sound than a rattle, like Crotalus.

Geographic range

Found in southeastern Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

, the eastern and northwestern United States

United States

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

, as well as isolated populations in northern and central 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...

.

Venom

Although bites from Sistrurus species are regarded as less dangerous to humans than those from Crotalus

Crotalus

Crotalus is a genus of venomous pit vipers found only in the Americas from southern Canada to northern Argentina. The name is derived from the Greek word krotalon, which means "rattle" or "castanet", and refers to the rattle on the end of the tail which makes this group so distinctive...

 rattlesnakes, primarily due to their lower venom yield, every venomous snake bite should be considered serious and prompt medical treatment should always be sought.

Species

Species	Taxon author	Subsp.*	Common name	Geographic range
S. catenatus Sistrurus catenatus Sistrurus catenatus is a venomous pitviper species found primarily in the United States. Three subspecies are currently recognized, including the nominate subspecies described here.-Description:...	(Rafinesque, 1818)	3	Massasauga	North America North America North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...  from southeastern Ontario Ontario Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....  (Canada Canada Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean... ) and western New York New York New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...  southwest to southeastern 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...  (USA United States The United States of America is a federal constitutional republic comprising fifty states and a federal district... ) and northern Tamaulipas Tamaulipas Tamaulipas officially Estado Libre y Soberano de Tamaulipas is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 43 municipalities and its capital city is Ciudad Victoria. The capital city was named after Guadalupe Victoria, the...  (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... ). In Mexico, isolated population exist in southern Nuevo León Nuevo León Nuevo León It is located in Northeastern Mexico. It is bordered by the states of Tamaulipas to the north and east, San Luis Potosí to the south, and Coahuila to the west. To the north, Nuevo León has a 15 kilometer stretch of the U.S.-Mexico border adjacent to the U.S...  and north-central Coahuila Coahuila Coahuila, formally Coahuila de Zaragoza , officially Estado Libre y Soberano de Coahuila de Zaragoza is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico... . It occurs in various habitats ranging from swamp Swamp A swamp is a wetland with some flooding of large areas of land by shallow bodies of water. A swamp generally has a large number of hammocks, or dry-land protrusions, covered by aquatic vegetation, or vegetation that tolerates periodical inundation. The two main types of swamp are "true" or swamp... s and marsh Marsh In geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss.... es to grassland Grassland Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica... s, usually below 1500 m (4,921.3 ft) altitude.
S. miliarius Sistrurus miliarius Sistrurus miliarius is a venomous pitviper species found in the southeastern United States. Three subspecies are currently recognized, including the nominate subspecies described here.-Description:... T	(Linnaeus Carolus Linnaeus Carl Linnaeus , also known after his ennoblement as , was a Swedish botanist, physician, and zoologist, who laid the foundations for the modern scheme of binomial nomenclature. He is known as the father of modern taxonomy, and is also considered one of the fathers of modern ecology... , 1766)	2	Pigmy rattlesnake	The southeastern United States Southeastern United States The Southeastern United States, colloquially referred to as the Southeast, is the eastern portion of the Southern United States. It is one of the most populous regions in the United States of America....  from eastern and southern North Carolina North Carolina North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...  southward through peninsular Florida Florida Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...  and westward to Oklahoma Oklahoma Oklahoma is a state located in the South Central region of the United States of America. With an estimated 3,751,351 residents as of the 2010 census and a land area of 68,667 square miles , Oklahoma is the 28th most populous and 20th-largest state...  and eastern Texas East Texas East Texas is a distinct geographic and ecological area in the U.S. state of Texas.According to the Handbook of Texas, the East Texas area "may be separated from the rest of Texas roughly by a line extending from the Red River in north central Lamar County southwestward to east central Limestone... . It occurs in flatwoods Flatwoods Flatwoods, Pineywoods, Longleaf Pine-Wiregrass Ecosystem refers to an ecological community in the Southeastern coastal plain of North America... , sandhill Sandhill A sandhill is a type of ecological community or xeric wildfire-maintained ecosystem. It is not the same as a sand dune. It features very short fire return intervals, one to five years. Without fire, sandhills undergo ecological succession and become more oak dominated.Entisols are the typical... s, mixed forests, floodplain Floodplain A floodplain, or flood plain, is a flat or nearly flat land adjacent a stream or river that stretches from the banks of its channel to the base of the enclosing valley walls and experiences flooding during periods of high discharge... s and around marshes and lakes.
S. ravus Sistrurus ravus Sistrurus ravus is a venomous pitviper species, found only in Mexico. Three subspecies are currently recognized, including the nominate subspecies described here.-Description:...	(Cope Edward Drinker Cope Edward Drinker Cope was an American paleontologist and comparative anatomist, as well as a noted herpetologist and ichthyologist. Born to a wealthy Quaker family, Cope distinguished himself as a child prodigy interested in science; he published his first scientific paper at the age of nineteen... , 1865)	2	Mexican pigmy rattlesnake	The mountains of central and southern Mexico, west of the Isthmus of Tehuantepec Isthmus of Tehuantepec The Isthmus of Tehuantepec is an isthmus in Mexico. It represents the shortest distance between the Gulf of Mexico and the Pacific Ocean, and prior to the opening of the Panama Canal was a major shipping route known simply as the Tehuantepec Route... , in the southeastern part of the Mexican Plateau Mexican Plateau The Central Mexican Plateau, also known as the Mexican Altiplano or Altiplanicie Mexicana, is a large arid-to-semiarid plateau that occupies much of northern and central Mexico... , in the highlands of Morelos Morelos Morelos officially Estado Libre y Soberano de Morelos is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 33 municipalities and its capital city is Cuernavaca.... , Tlaxcala Tlaxcala Tlaxcala officially Estado Libre y Soberano de Tlaxcala is one of the 31 states which along with the Federal District comprise the 32 federative entities of Mexico. It is divided into 60 municipalities and its capital city is Tlaxcala.... , Puebla Puebla Puebla officially Estado Libre y Soberano de Puebla is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 217 municipalities and its capital city is Puebla.... , Veracruz Veracruz Veracruz, formally Veracruz de Ignacio de la Llave officially Estado Libre y Soberano de Veracruz de Ignacio de la Llave , is one of the 31 states that, along with the Federal District, comprise the 32 federative entities of Mexico. It is divided in 212 municipalities and its capital city is... , Oaxaca Oaxaca Oaxaca , , officially Estado Libre y Soberano de Oaxaca is one of the 31 states which, along with the Federal District, comprise the 32 federative entities of Mexico. It is divided into 571 municipalities; of which 418 are governed by the system of customs and traditions...  and the Sierra Madre del Sur Sierra Madre del Sur The Sierra Madre del Sur is a mountain range in southern Mexico, extending from southern Michoacán east through Guerrero, to the Istmo de Tehuantepec in eastern Oaxaca.-Geography:...  in Guerrero Guerrero Guerrero officially Estado Libre y Soberano de Guerrero is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 81 municipalities and its capital city is Chilpancingo.... .

• ) Not including the nominate subspecies.
  

^T) Type species

Type species

In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...

.

External links

• Sistrurus at Herpbreeder.com. Accessed 5 December 2007.