Common names: Andean lancehead.

Bothrops andianus 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...

 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...

 found in the Andes

Andes

The Andes is the world's longest continental mountain range. It is a continual range of highlands along the western coast of South America. This range is about long, about to wide , and of an average height of about .Along its length, the Andes is split into several ranges, which are separated...

 in 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...

. No 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...

 are currently recognized.

Description

A terrestrial species, adults usually grow to 60-70 cm in length with a maximum of 125.8 cm.

The scalation includes 21-25 (usually 21-23) rows of dorsal scales

Dorsal scales

In snakes, the dorsal scales are the longitudinal series of plates that encircle the body, but do not include the ventral scales.When counting dorsal scales, numbers are often given for three points along the body, for example 19:21:17...

 at midbody, 157-174/169-179 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...

 in males/females and 52-63/49-58 mostly divided subcaudal scales

Subcaudal scales

In snakes, the subcaudal scales are the enlarged plates on the underside of the tail. These scales may be either single or divided and are preceded by the anal scale....

. On the head, the rostral scale is usually a little higher (up to 50%) than it is wide, the loreal scale is rectangular and wider than it is high, there are 3-10 keeled intersupraoculars, 7 supralabial scales

Supralabial scales

In reptiles, the supralabial scales, also called upper-labials, are those scales that border the mouth opening along the upper jaw. They do not include the median scale . The term labial originates from Labium , which refers to any lip-like structure...

 with the second usually fused with the prelacunal to form a lacunolabial, and 8-11 sublabial scales

Sublabial scales

In reptiles, the sublabial scales, also called lower-labials or infralabials, are those scales that border the mouth opening along the lower jaw. They do not include the median scale . The term labial originates from Labium , which refers to any lip-like structure...

.

The color pattern consists of an olive gray to brown ground color, which is occasionally darker anteriorly, overlaid with a series of 18-25 dark dorsolateral blotches that usually oppose middorsally, but may alternate. These markings are triangular, or in the shape of a headphone, and have black edges followed by a peripheral pale border. The belly is cream to yellow with heavy dark gray, brown or black mottling. On the head, the canthus and supralabials are a lighter than the overall ground color while the dorsum is darker. A well-defined postorbital stripe is present that is dark chocolate brown or black in color.

Geographic range

Found in 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 southern mountains of Peru

Peru

Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....

 in the departments of Cuzco

Cusco Region

Cusco is a region in Peru. It is bordered by the Ucayali Region on the north; the Madre de Dios and Puno regions on the east; the Arequipa Region on the south; and the Apurímac, Ayacucho and Junín regions on the west...

 and Puno

Puno Region

Puno is a region in southeastern Peru. It is bordered by Bolivia on the east, the Madre de Dios Region on the north, the Cusco and Arequipa regions on the west, the Moquegua Region on the southwest, and the Tacna Region on the south...

 at elevations of 1800-3300 m. The type locality given is "Machu Picchu

Machu Picchu

Machu Picchu is a pre-Columbian 15th-century Inca site located above sea level. It is situated on a mountain ridge above the Urubamba Valley in Peru, which is northwest of Cusco and through which the Urubamba River flows. Most archaeologists believe that Machu Picchu was built as an estate for...

, Department of Cuzco, Peru, about 9,000-10,000 ft. altitude" (2,743-3,048 m).