Common names: hognosed pitvipers.

Porthidium 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...

 pitvipers

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...

 found in 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...

 and southward to northern South America

South America

South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

. The name is derived from 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;...

 words portheo and the suffix -idus, which means "destroy" and "having the nature of"; apparently a reference to the venom. Seven 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

This is a groups of group of small species, adults ranging in size from 55 cm (P. dunni

Porthidium dunni

Porthidium dunni is a venomous pitviper species found in Mexico. No subspecies are currently recognized.-Description:Adults are usually 30-40 cm in length, with a maximum of 57 cm. A moderately stout and terrestrial species...

 and P. yucatanicum

Porthidium yucatanicum

Porthidium yucatanicum is a venomous pitviper species found in Mexico. No subspecies are currently recognized.-Description:Adults are usually 35-45 cm in length, although some specimens may exceed than 55 cm. The females tend to be larger than the males. Moderately stout and terrestrial.-Geographic...

) to 75 cm in length (P. lansbergii

Porthidium lansbergii

Porthidium lansbergii is a venomous pitviper species found in Central and South America. Currently, four subspecies are recognized, including the nominate subspecies described here.-Description:...

 and P. ophryomegas

Porthidium ophryomegas

Porthidium ophryomegas is a venomous pitviper species found in Central America. No subspecies are currently recognized.-Description:Adults usually grow to a length of 40-60 cm and have a relatively slender build. Females grow larger than males and are often more than 60 cm in length, while males...

). In addition, the body shape ranges from relatively slender (P. ophryomegas) to relatively stout (P. nasutum

Porthidium nasutum

Porthidium nasutum is a venomous pitviper species found in Mexico, Central America and northern South America. No subspecies are currently recognized.-Description:...

). All have a sharply defined canthus rostralis

Canthus (snake)

In snakes and amphibians, the canthus, canthal ridge or canthus rostralis, is the angle between the flat crown of the head and the side of the head between the eye and the snout. More specifically, between the supraocular scale and the rostral scale. It is defined as a sharp ridge in many viperids,...

 and a rostral scale that is higher than it is broad. The tip of the snout may slightly to moderately elevated (P. hespere

Porthidium hespere

Porthidium hespere is a venomous pitviper species found in western Mexico. No subspecies are currently recognized.-Description:Know from only four specimens: two females with locality data and two other specimens without. The former were moderately stout and were 31.5 and 57.9 cm in length...

, P. lansbergii, P. ophryomegas and P. volcanicum

Porthidium volcanicum

Porthidium volcanicum is a venomous pitviper species found in Costa Rica. No subspecies are currently recognized.-Description:Adults are moderately stout with females growing to 31-53.6 cm in length...

), strongly elevated (P. dunni and P. yucatanicum), or not elevated at all.

All species have a color pattern that usually consists of brown or gray color overlaid with a series of dark paraventral

Paraventral scales

In snakes, the paraventral scales are the longitudinal rows of dorsal scales that contact the ventral scales. These are the first rows of dorsal scales on either side of the body and are usually slightly larger than the scales located more dorsally...

 blotches that are separates by a pale and narrow vertebral stripe. The blotches are square, rectangular or triangular in shape. With some species, the color pattern is determined by the sex.

Geographic range

Found in 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...

 (Colima

Colima

Colima is one of the 31 states which, with the Federal District, make up the 32 Federal Entities of Mexico. It shares its name with its capital and main city, Colima....

, 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 Chiapas

Chiapas

Chiapas officially Estado Libre y Soberano de Chiapas is one of the 31 states that, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 118 municipalities and its capital city is Tuxtla Gutierrez. Other important cites in Chiapas include San Cristóbal de las...

 on the Pacific side, the Yucatan Peninsula

Yucatán Peninsula

The Yucatán Peninsula, in southeastern Mexico, separates the Caribbean Sea from the Gulf of Mexico, with the northern coastline on the Yucatán Channel...

 on the Atlantic side) southward through Central America

Central America

Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...

 to northern South America

South America

South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

 (Ecuador

Ecuador

Ecuador , officially the Republic of Ecuador is a representative democratic republic in South America, bordered by Colombia on the north, Peru on the east and south, and by the Pacific Ocean to the west. It is one of only two countries in South America, along with Chile, that do not have a border...

 in the Pacific lowlands, northern Venezuela

Venezuela

Venezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south...

 in the Atlantic lowlands).

Species

Species	Taxon author	Subsp.*	Common name	Geographic range
P. dunni Porthidium dunni Porthidium dunni is a venomous pitviper species found in Mexico. No subspecies are currently recognized.-Description:Adults are usually 30-40 cm in length, with a maximum of 57 cm. A moderately stout and terrestrial species...	(Hartweg Norman Edouard Hartweg Dr. Norman Edouard "Kibe" Hartweg was an American herpetologist, Curator of Herpetology for the Museum of Zoology at the University of Michigan, and president of the American Society of Ichthyologists and Herpetologists...  & Oliver, 1938)	0	Dunn's hognosed pitviper	Southern 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 the Pacific lowlands of 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 western Chiapas Chiapas Chiapas officially Estado Libre y Soberano de Chiapas is one of the 31 states that, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 118 municipalities and its capital city is Tuxtla Gutierrez. Other important cites in Chiapas include San Cristóbal de las... .
P. hespere Porthidium hespere Porthidium hespere is a venomous pitviper species found in western Mexico. No subspecies are currently recognized.-Description:Know from only four specimens: two females with locality data and two other specimens without. The former were moderately stout and were 31.5 and 57.9 cm in length...	(Campbell J.A. Campbell J.A. Campbell can refer to:* John Argentine Campbell, Scottish rugby player* James Campbell... , 1976)	0	Colima hognosed pitviper	Western Mexico (Colima Colima Colima is one of the 31 states which, with the Federal District, make up the 32 Federal Entities of Mexico. It shares its name with its capital and main city, Colima.... ).
P. lansbergii Porthidium lansbergii Porthidium lansbergii is a venomous pitviper species found in Central and South America. Currently, four subspecies are recognized, including the nominate subspecies described here.-Description:...	(Schlegel Hermann Schlegel Hermann Schlegel was a German ornithologist and herpetologist.-Early life and education:Schlegel was born at Altenburg, the son of a brassfounder. His father collected butterflies, which stimulated Schlegel's interest in natural history... , 1841)	3	Lansberg's hognosed pitviper	Extreme eastern Central America Central America Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...  in the xeric coastal lowlands of central and eastern Panama Panama Panama , officially the Republic of Panama , is the southernmost country of Central America. Situated on the isthmus connecting North and South America, it is bordered by Costa Rica to the northwest, Colombia to the southeast, the Caribbean Sea to the north and the Pacific Ocean to the south. The... . In northern South America South America South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...  in the Atlantic lowlands of Colombia Colombia Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...  and northern Venezuela Venezuela Venezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south... , as well as the Pacific lowlands of Ecuador Ecuador Ecuador , officially the Republic of Ecuador is a representative democratic republic in South America, bordered by Colombia on the north, Peru on the east and south, and by the Pacific Ocean to the west. It is one of only two countries in South America, along with Chile, that do not have a border... .
P. nasutum Porthidium nasutum Porthidium nasutum is a venomous pitviper species found in Mexico, Central America and northern South America. No subspecies are currently recognized.-Description:... T	(Bocourt Marie Firmin Bocourt Marie Firmin Bocourt was a French zoologist and artist.In zoology, Bocourt collaborated with Auguste Duméril. In 1861, he was sent to Thailand , where he explored the fauna and brought back an important collection of specimens... , 1868)	0	Rainforest hognosed pitviper	Southern Mexico southward through Central America to western Colombia and northwestern Ecuador in South America. Inhabits the Atlantic lowlands from Mexico (Tabasco Tabasco Tabasco officially Estado Libre y Soberano de Tabasco is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 17 municipalities and its capital city is Villahermosa....  and Chiapas) through Belize Belize Belize is a constitutional monarchy and the northernmost country in Central America. Belize has a diverse society, comprising many cultures and languages. Even though Kriol and Spanish are spoken among the population, Belize is the only country in Central America where English is the official... , Guatemala Guatemala Guatemala is a country in Central America bordered by Mexico to the north and west, the Pacific Ocean to the southwest, Belize to the northeast, the Caribbean to the east, and Honduras and El Salvador to the southeast... , Honduras Honduras Honduras is a republic in Central America. It was previously known as Spanish Honduras to differentiate it from British Honduras, which became the modern-day state of Belize... , Nicaragua Nicaragua Nicaragua is the largest country in the Central American American isthmus, bordered by Honduras to the north and Costa Rica to the south. The country is situated between 11 and 14 degrees north of the Equator in the Northern Hemisphere, which places it entirely within the tropics. The Pacific Ocean...  and Costa Rica Costa Rica Costa Rica , officially the Republic of Costa Rica is a multilingual, multiethnic and multicultural country in Central America, bordered by Nicaragua to the north, Panama to the southeast, the Pacific Ocean to the west and the Caribbean Sea to the east....  to eastern Panama and northwestern Colombia. In the Pacific lowlands, it occurs in southwestern Costa Rica Costa Rica Costa Rica , officially the Republic of Costa Rica is a multilingual, multiethnic and multicultural country in Central America, bordered by Nicaragua to the north, Panama to the southeast, the Pacific Ocean to the west and the Caribbean Sea to the east.... , central and eastern Panama, continuing on to northwestern Ecuador. It is found in mesic lowland broadleaf or rainforest from sea level to elevation of about 900 m.
P. ophryomegas Porthidium ophryomegas Porthidium ophryomegas is a venomous pitviper species found in Central America. No subspecies are currently recognized.-Description:Adults usually grow to a length of 40-60 cm and have a relatively slender build. Females grow larger than males and are often more than 60 cm in length, while males...	(Bocourt Marie Firmin Bocourt Marie Firmin Bocourt was a French zoologist and artist.In zoology, Bocourt collaborated with Auguste Duméril. In 1861, he was sent to Thailand , where he explored the fauna and brought back an important collection of specimens... , 1869)	0	Slender hognosed pitviper	Central America in Guatemala, El Salvador El Salvador El Salvador or simply Salvador is the smallest and the most densely populated country in Central America. The country's capital city and largest city is San Salvador; Santa Ana and San Miguel are also important cultural and commercial centers in the country and in all of Central America... , Honduras, Nicaragua and Costa Rica.
P. volcanicum Porthidium volcanicum Porthidium volcanicum is a venomous pitviper species found in Costa Rica. No subspecies are currently recognized.-Description:Adults are moderately stout with females growing to 31-53.6 cm in length...	Solorzano, 1995	0	Ujarran hognosed pitviper	Volcán de Buenos Aires and Valle del General in Puntarenas Province Puntarenas Province Puntarenas is a province of Costa Rica. It is located in the western part of the country, covering most of Costa Rica's Pacific Ocean coast, and it is the largest province in Costa Rica. Clockwise from the northwest it borders on the provinces Guanacaste, Alajuela, San José and Limón, and the... , Costa Rica.
P. yucatanicum Porthidium yucatanicum Porthidium yucatanicum is a venomous pitviper species found in Mexico. No subspecies are currently recognized.-Description:Adults are usually 35-45 cm in length, although some specimens may exceed than 55 cm. The females tend to be larger than the males. Moderately stout and terrestrial.-Geographic...	(Smith Hobart M. Smith Hobart Muir Smith, born Frederick William Stouffer , is an American herpetologist. He was born in Stanwood, Iowa, United States. He has been credited with describing several new species of North American reptiles and amphibians... , 1941)	0	Yucatán hognosed pitviper	Northern half of the Yucatán Peninsula Yucatán Peninsula The Yucatán Peninsula, in southeastern Mexico, separates the Caribbean Sea from the Gulf of Mexico, with the northern coastline on the Yucatán Channel...  in Mexico.

• ) 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

• Porthidium at Herpbreeder.com. Accessed 15 September 2007.