Philodryas olfersii

Common names for P. olfersii include Lichtenstein's green racer,[2][3] South American green racer,[4] and eastern green whiptail,[5][6] and in Brazil, cobra-cipó, cobra de São João,[7] cobra-facão, cobra-verde, and mboi-obi.[8]

The specific name, olfersii, is in honor of German naturalist Ignaz von Olfers.[9]

P. olfersii is native to southern South America, including Bolivia, northwestern Paraguay, northern Argentina.[2]

P. olfersii reaches 1 to 1.5 meters (about 40 to 60 inches) in maximum total length (including tail).[3]

Dorsally, it is green in color;[10] ventrally, it is yellowish.[1]

The dorsal scales are smooth, without apical pits, and are arranged in 19 rows at midbody.[1]

P. olfersii can be found in many habitat types, including the Cerrado, Caatinga, forests, forest transition,[7] and restinga.[11]

The species P. olfersii is often arboreal,[6] but it also forages on the ground.[5] It is diurnal,[6] though it has been observed mating late in the evening.[12]

Prey items of P. olfersii include rodents, lizards, amphibians, and birds,[6] especially nestlings.[5] They will also eat other snakes, including ones almost as large as themselves.[8]

P. olfersii is oviparous. Each egg measures about 5 centimeters (about 2 inches).[6] The clutch size is 4 to 11 eggs, with larger females producing more eggs than smaller ones.[13]

Snake species in the genus Philodryas are not considered venomous.[14][15] However, P. olfersii is a venomous snake, and there have been reports of serious bites causing local and systemic effects requiring medical treatment.[14] The most common symptoms are pain, swelling, erythema, and ecchymosis.[16] 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,[14] even progressing to the neck, chest,[7] and abdomen.[4] Stiffness may affect the entire limb.[10] Patients complaining of snakebite may be given an antivenom for Bothrops snake venom, which is inappropriate for the treatment of Philodryas bites.[14][15] Philodryas does not cause the coagulopathy that Bothrops does.[7] The bite of this snake is almost never lethal; only one fatality has been reported, and that in a child.[3]

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.[15] The secretion contains toxins such as serine proteases, metalloproteases, C-type lectins, cysteine-rich secretory proteins, and a C-type natriuretic peptide.[17]

P. olfersii is host to a newly described species of parasitic protozoan, Caryospora olfersii. This snake has also been recorded carrying C. braziliensis.[11]

Some sources do not recognize any subspecies of P. olfersii.[8][18] However, other sources recognize the following three subspecies, including the nominotypical subspecies:[10][2][19]

• Philodryas olfersii herbeus (Wied, 1825)
• Philodryas olfersii latirostris (Cope, 1862)
• Philodryas olfersii olfersii (Lichtenstein, 1825)

• Lichtenstein H (1823). Verseichniss der Doubletten des zoologischen Museums der Königl. Universität zu Berlin nebst Beschreibung vieler bisher unbekannter Arten von Säugethieren, Vögeln, Amphibien und Fischen herausgegeben. Berlin: Königlich Preussische Akademie der Wissenschaften. (T. Trautwein, printer). x + 118 pp. + one plate. (Coluber olfersii, new species, pp. 104–105).