Philodryas olfersii

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

Philodryas olfersii
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Squamata
Suborder:	Serpentes
Family:	Colubridae
Genus:	Philodryas
Species:	P. olfersii
Binomial name
Philodryas olfersii (Lichtenstein, 1823)
Synonyms[1]
Coluber olfersii Lichtenstein, 1823 Herpetodryas olfersii — Schlegel, 1837 Dryophylax olfersii — A.M.C. Duméril, Bibron & A.H.A. Duméril, 1854 Philodryas olfersii — Günther, 1885

Common names

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]

Etymology

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

Geographic range

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

Description

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]

Habitat

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

Behavior

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]

Diet

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]

Reproduction

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]

Venom

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]

Parasites

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

Subspecies

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)

References

1. Boulenger GA (1896). Catalogue of the Snakes in the British Museum (Natural History). Volume III., Containing the Colubridæ (Opisthoglyphæ and Proteroglyphæ) ... London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). xiv + 727 pp. + Plates I-XXV. (Philodryas olfersii, pp. 129-130).
2. Philodryas olfersii. The Reptile Database.
3. O'Shea M (2008). Venomous Snakes of the World. New Holland Publishers. pg. 53.
4. Weinstein SA, et al. (2011). "Venomous" Bites from Non-Venomous Snakes: A Critical Analysis of Risk and Management of "Colubrid" Snake Bites. Elsevier. pg. 104.
5. Sazima I, Marques OAV (2007). "A reliable customer: Hunting site fidelity by an actively foraging neotropical colubrid snake". Herpetological Bulletin (99): 36-38.
6. Barbo FE, et al. (2011). "Diversity, natural history, and distribution of snakes in the municipality of São Paulo". South American Journal of Herpetology 6 (3): 135-160.
7. Correia JM, et al. (2010). "Poisoning due to Philodryas olfersii (Lichtenstein, 1823) attended at Restauração Hospital in Recife, State of Pernambuco, Brazil: Case report". Revista da Sociedade Brasileira de Medicina Tropical 43 (3): 336-338.
8. Freiberg M (1982). Snakes of South America. Hong Kong: T.F.H. Publications. 189 pp. ISBN 0-87666-912-7. (Philodryas olfersii, pp. 106, 137 + photographs on pp. 21, 146).
9. Beolens, Bo; Michael Watkins; Michael Grayson (2011). The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. xiii + 312 pp. ISBN 978-1-4214-0135-5. (Philodryas olfersii, p. 157).
10. Kuch U (1999). "Notes on two cases of human envenomation by the South American colubrid snakes Philodryas olfersii latirostris Cope, 1862 and Philodryas chamissonis (Wiegmann, 1834) (Squamata: Serpentes: Colubridae)". Herpetozoa 12 (1/2): 11-16.
11. Viana LA, et al. (2013). "A new species of Caryospora Léger, 1904 (Apicomplexa: Eimeriidae) from the snake Philodryas olfersii Lichtenstein (Colubridae) from a coastal habitat in Brazil". Syst. Parasitol. 85 (2): 195-199.
12. Dourado de Mesquita PCM, et al. (2012). "Philodryas olfersii (Squamata, Serpentes, Dipsadidae): Nocturnal mating behavior". Archived 2013-12-27 at the Wayback Machine Herpetologia Brasileira 1 (1): 41.
13. Dourado de Mesquita PCM, et al. (2013). "Reproductive biology of Philodryas olfersii (Serpentes, Dipsadidae) in a subtropical region of Brazil". The Herpetological Journal 23 (1): 39-44.
14. Araújo ME, Santos AC (1997). "Cases of human envenoming caused by Philodryas olfersii and Philodryas patagoniensis (Serpentes: Colubridae)". Rev. Soc. Bras. Med. Trop. 30 (6): 517-519.
15. Acosta de Perez O, et al. (2003). "Edematogenic and myotoxic activities of the Duvernoy's gland secretion of Philodryas olfersii from the north-east region of Argentina". Biocell 27 (3): 363-370.
16. Ribeiro LA, et al. (1999). "Bites by the colubrid snake Philodryas olfersii: A clinical and epidemiological study of 43 cases". Toxicon 37 (6): 943-948.
17. Ching ATC, et al. (2006). "Some aspects of the venom proteome of the Colubridae snake Philodryas olfersii revealed from a Duvernoy’s (venom) gland transcriptome". FEBS Letters 580 (18): 4417-4422.
18. "Philodryas olfersii ". ITIS (Integrated Taxonomic Information System). www.itis.gov.
19. "Philodryas olfersii ". Dahms Tierleben. www.dahmstierleben.de/systematik/Reptilien/Squamata/Serpentes/colubroidea/colubridae/dipsadinae#section-58.

Further reading

• 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).