Yarará

Bothrops jararaca
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Squamata
Suborder:	Serpentes
Family:	Viperidae
Genus:	Bothrops
Species:	B. jararaca
Binomial name
Bothrops jararaca (Wied-Neuwied, 1824)
Synonyms
Cophias Jajaraca [sic] Wied-Neuwied, 1824 Bothrops leucostigma Wagler, 1824 Cophias Jararaca Wied-Neuwied, 1824 [Cophias] Jararaca – Wied-Neuwied, 1825 C[ophias]. Jararakka [sic] – Wied-Neuwied, 1825 Cophias Jararaca – Wagler, 1830 T[rigonocephalus]. jararaca – Schlegel, 1837 Craspedocephalus brasiliensis Günther, 1858 Crotalus Craspedocephalus Brasiliensis – Higgins, 1873 Bothrops jararaca – Golay et al., 1993 Bothropoides jararaca – Fenwick et al., 2009

Bothrops jararaca — known as the jararaca (or the yarara) — is a species of pit viper endemic to southern Brazil, Paraguay, and northern Argentina. The specific name, jararaca, is derived from the Tupi words yarará and ca, which mean "large snake". Within its geographic range, it is often abundant and is an important cause of snakebite. No subspecies are currently recognized.

The drugs known as angiotensin converting enzyme (ACE) inhibitors, used for the treatment of hypertension and some types of congestive heart failure, were developed from a peptide found in the venom of this species.

This is a slender and terrestrial species that grows to a maximum total length of 160 cm (63 in), although the average total length is much less.

The head scalation includes 5-12 intersupraoculars that are weakly keeled, 7-9 supralabials (usually 8) of which the second is fused with the prelacunal to form a lacunolabial, and 9-13 sublabials (usually 10-12). Midbody, there are 20-27 rows of dorsal scales (usually 23-25). The ventrals number 170-216 (rarely 218) and the 51-71 subcaudals are mostly paired.

The color pattern is extremely variable, consisting of a dorsal ground color that may be tan, brown, gray, yellow, olive, or almost maroon. Midbody, this color is usually somewhat lighter than the head, anterior and posterior. The dorsal ground color is overlaid with a series of pale-edged, dark brown subtriangular or trapezoidal markings on either side of the body, the apices of which reach the vertebral line. These marking may be situated opposite each other, or partially or completely juxtaposed; most specimens have a pattern with all three variations. In juveniles, the tip of the tail is white.

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Wikipedia