Lichtenstein's Green Racer

Philodryas olfersii is a species of venomous snake in the subfamily Dipsadinae of the family Colubridae. The species is endemic to South America.

Common names

Common names for Philodryas olfersii include Lichtenstein's green racer, South American green racer, and eastern green whiptail,

Etymology

The specific name, olfersii, is in honor of German naturalist Ignaz von Olfers.

Geographic range

Philodryas olfersii is native to southern South America, including northern Argentina, Brazil, Bolivia, and northwestern Paraguay.

Description

Philodryas olfersii reaches 1 to 1.5 meters (about 40 to 60 inches) in maximum total length (including tail).

Dorsally, it is green in color; ventrally, it is yellowish.

The dorsal scales are smooth, without apical pits, and are arranged in 19 rows at midbody.

Habitat

Philodryas olfersii can be found in many habitat types, including the Cerrado, Caatinga, forest, forest transition, and restinga. It has been found at altitudes from sea level to 1,700 m (5,600 ft).

Behavior

The species Philodryas olfersii is often arboreal, but it also forages on the ground. It is diurnal, though it has been observed mating late in the evening.

Diet

Prey items of Philodryas olfersii include small rodents, lizards, amphibians, and birds, especially nestlings. They will also eat other snakes, including ones almost as large as themselves.

Reproduction

Philodryas olfersii is oviparous. Each egg measures about 5 centimeters (about 2 inches). Clutch size is 4 to 11 eggs, with larger females producing more eggs than smaller females.

Venom

Philodryas olfersii is a venomous snake, and there have been reports of serious bites causing local and systemic effects requiring medical treatment. The venom of P. olfersii is highly hemorrhagic, fibrinogenolytic, edematic, and has proteolytic activity 208% higher than Bothrops jararaca, in addition to containing neurotoxic properties. In mice, doses such as 5.6 μg / 20g resulted in neurotoxic effects, which included dyspnea, equilibrium alterations, posterior limbs paralysis, flaccid paralysis, and relaxation of the urinary sphincter. In laboratory mice, the venom of this species has an LD50 of 2.79 ± 0.58 mg / kg (intraperitoneal), equivalent to the lethality of Bothrops asper. However, due to the anatomy of their inoculating teeth located in the posterior region of the maxilla, these snakes have difficulty in inoculating venom, sometimes giving a "dry" bite. The most common symptoms are pain, swelling, erythema, and ecchymosis. There may be a pulsing sensation or numbness at the bite site. Some pus can develop and nearby lymph nodes may enlarge. Bruising or other discoloration can appear quite a distance from the wound site, sometimes occurring far up the arm after a hand wound, even progressing to the neck, chest, and abdomen. Stiffness may affect the entire limb. Patients complaining of snakebite may be given an antivenom for Bothrops snake venom, which is inappropriate for the treatment of Philodryas bites. Philodryas does not cause the coagulopathy that Bothrops does. Only one fatality has been reported, and that in a child.