Philodryas olfersii

Philodryas olfersii is a species of venomous snake in the family Colubridae. The species is endemic to South America.
Common names.
Common names for "P. olfersii" include Lichtenstein's green racer, South American green racer, and eastern green whiptail, and in Brazil, cobra-cipó, cobra de São João, cobra-facão, cobra-verde, and mboi-obi.
Etymology.
The specific name, "olfersii", is in honor of German naturalist Ignaz von Olfers.
Geographic range.
"P. olfersii" is native to southern South America, including Brazil, Bolivia, northwestern Paraguay, northern Argentina.
Description.
"P. 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.
"P. olfersii" can be found in many habitat types, including the Cerrado, Caatinga, forests, forest transition, and restinga.
Behavior.
The species "P. 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 "P. olfersii" include rodents, lizards, amphibians, and birds, especially nestlings. They will also eat other snakes, including ones almost as large as themselves.
Reproduction.
"P. olfersii" is oviparous. Each egg measures about 5 centimeters (about 2 inches). The clutch size is 4 to 11 eggs, with larger females producing more eggs than smaller ones.
Venom.
Snake species in the genus "Philodryas" are not considered venomous. However, "P. 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 and edematic, also has proteolytic activity 208% higher than "Bothrops jararaca", in addition to containing neurotoxic properties, In mice, doses such as 5.6 µg / 20g result 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.
The secretion that causes injury to bite victims is produced in the snake's Duvernoy's gland and channeled into its prey via a grooved tooth. It is myotoxic, causing muscle damage; muscle tissue hemorrhages and becomes necrotic. The secretion contains toxins such as serine proteases, metalloproteases, C-type lectins, cysteine-rich secretory proteins, and a C-type natriuretic peptide.
Parasites.
"P. olfersii" is host to a newly described species of parasitic protozoan, "Caryospora olfersii". This snake has also been recorded carrying "C. braziliensis".
Subspecies.
Some sources do not recognize any subspecies of "P. olfersii". However, other sources recognize the following three subspecies, including the nominotypical subspecies: