Bothrops jararaca (Wied-Neuwied, 1824)

Species Identification and Size

Bothrops jararaca (Wied-Neuwied, 1824) is a slender terrestrial viper species that reaches a maximum total length of 160 cm (63 in), with an average total length that is considerably shorter.

Head Scalation

Its head scalation features 5–12 weakly keeled intersupraocular scales, 7–9 supralabial scales (most often 8), where the second supralabial is fused with the prelacunal to form a lacunolabial structure, and 9–13 sublabial scales (most often 10–12).

Dorsal and Ventral Scale Counts

At midbody, it has 20–27 rows of dorsal scales, most commonly 23–25. It has 170–216 ventral scales (rarely 218), and 51–71 mostly paired subcaudal scales.

Dorsal Ground Coloration

Its color pattern is extremely variable: the dorsal ground color can be tan, brown, gray, yellow, olive, or almost maroon, and the midbody ground color is typically somewhat lighter than the ground color of the head, anterior body, and posterior body.

Dorsal Body Markings

Overlaid on the dorsal ground color is a series of pale-edged, dark brown subtriangular or trapezoidal markings along each side of the body; the apices of these markings reach the vertebral line. The markings may be positioned opposite one another, or partially or completely juxtaposed, with most individuals having a pattern that includes all three variations.

Juvenile Traits

Juvenile individuals have a white tail tip.

Head Stripe Pattern

On each side of the head, there is a prominent dark brown stripe that runs from behind the eye back to the angle of the mouth, usually touching the last three supralabials. This stripe is bordered dorsally by a distinct pale area.

Head Soft Tissue Coloration

The tongue is black, and the iris ranges from gold to greenish gold, with slightly darker reticulations.

Geographic Range

This snake is native to southern Brazil, northeastern Paraguay, and Misiones Province in northern Argentina. The species' type locality was recorded as "Lagoa d'Arara am Mucurí" (Brazil) by Wied-Neuwied in 1825.

Elevational Range

Its elevational range extends from near sea level to over 1,000 m (3,280 ft).

Habitat Types

It primarily inhabits dense tropical perennial forests along the Atlantic coast up to around 1,000 m (3,280 ft) above sea level. It also occurs in thickets, savannas, semitropical highland forests, and cultivated fields.

Habitat Use by Age Class

While adults are mainly terrestrial, juveniles are also arboreal.

Mating Period and Behavior

Mating occurs between April and May. Males mate with multiple females, and males fight with one another to access females.

Reproductive Cycle

Females of this species undergo secondary vitellogenesis. Ovulation and fertilization take place in the spring, between October and December or January, and females give birth between February and April.

Reproductive Output and Maturity

On average, females produce 10 to 14 offspring per breeding season. Both sexes are thought to reach sexual maturity at two years of age.

Venom-Derived ACE Inhibitors

Angiotensin converting enzyme inhibitors (ACE inhibitors), a class of drugs used to treat hypertension and some forms of congestive heart failure, were developed from a peptide discovered in the venom of this species in 1965 by Brazilian scientist Sérgio Henrique Ferreira.

Venom-Derived Antihemorrhagic Drug

A haemocoagulase enzyme derived from this species' venom is used as an antihemorrhagic drug.