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Philodryas olfersii

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Philodryas olfersii
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Serpentes
Family: Colubridae
Genus: Philodryas
Species:
P. olfersii
Binomial name
Philodryas olfersii
(Lichtenstein, 1823)
Synonyms[2]

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

Common names

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Common names for P. olfersii include Lichtenstein's green racer,[3][4] South American green racer,[5] and eastern green whiptail,[6][7]

Etymology

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The specific name, olfersii, is in honor of German naturalist Ignaz von Olfers.[8]

Geographic range

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P. olfersii is native to southern South America, including northern Argentina, Brazil, Bolivia, and northwestern Paraguay.[3]

Description

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P. olfersii reaches 1 to 1.5 meters (about 40 to 60 inches) in maximum total length (including tail).[4]

Dorsally, it is green in color;[9] ventrally, it is yellowish.[2]

The dorsal scales are smooth, without apical pits, and are arranged in 19 rows at midbody.[2]

Habitat

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P. olfersii can be found in many habitat types, including the Cerrado, Caatinga, forest, forest transition,[10] and restinga.[11] It has been found at altitudes from sea level to 1,700 m (5,600 ft).[1]

Behavior

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The species P. olfersii is often arboreal,[7] but it also forages on the ground.[6] It is diurnal,[7] though it has been observed mating late in the evening.[12]

Diet

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Prey items of P. olfersii include small rodents, lizards, amphibians, and birds,[1][7] especially nestlings.[6] They will also eat other snakes, including ones almost as large as themselves.[13]

Reproduction

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P. olfersii is oviparous.[1][3] Each egg measures about 5 centimeters (about 2 inches).[7] The clutch size is 4 to 11 eggs, with larger females producing more eggs than smaller ones.[14]

Venom

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P. olfersii is a venomous snake, and there have been reports of serious bites causing local and systemic effects requiring medical treatment.[15] 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.[16][17][18] The most common symptoms are pain, swelling, erythema, and ecchymosis.[19] 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,[15] even progressing to the neck, chest,[10] and abdomen.[5] Stiffness may affect the entire limb.[9] Patients complaining of snakebite may be given an antivenom for Bothrops snake venom, which is inappropriate for the treatment of Philodryas bites.[15][20] Philodryas does not cause the coagulopathy that Bothrops does.[10] Only one fatality has been reported, and that in a child.[4]

The secretion that causes death to prey (or injury to bite victims) is produced in the snake's Duvernoy's gland at the rear of the mouth, and ”chewed” into its prey via a grooved tooth; this unique method of envenomation takes considerably more physical effort, from the snake, than it would with a more lethally venomous species (such as vipers, cobras, mambas, etc.). The majority of other venomous snakes will deliver one, swift bite of venom (via two frontal fangs, shaped like needles) before retreating and waiting for the venom to take effect on their prey in question. In the same way, a rear-fanged snake is less likely to bite a human, because it doesn’t view such a large potential predator as prey, and therefore is less inclined to exert the needed force to envenomate—this does not mean they will NOT bite, it is simply less common in rear-fanged snakes than other, more lethal, species. Nevertheless, their venom is myotoxic, causing muscle damage; muscle tissue hemorrhages and becomes necrotic.[20] The secretion contains toxins such as serine proteases, metalloproteases, C-type lectins, cysteine-rich secretory proteins, and a C-type natriuretic peptide.[21] Since Philodryas olfersii has difficulty in inoculating venom and produces small amounts of venom, accidents by this species are generally not serious, having a protein content of only 932 micrograms, and generally, 75 to 90% of the venom is composed of proteins. More recently, there was a severe case for this species, in which the victim let the snake bite for a long time, allowing it to inject a significant amount of venom. The symptoms started with a lot of swelling and bruises. The accident at first was not taken seriously as bites by Philodryas aren't serious in general. At the beginning, the victim only had pain and swelling. However, over time, the pain intensified, and the victim reported that she was in severe pain from the fingertip to the chest. Examinations showed that the venom caused clotting problems, affected liver enzymes and 50% of the liver. Swelling in the two arms was severe, with risk of thrombosis, and fasciotomy or even amputation was almost necessary.[22][23][24]

Parasites

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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

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Some sources do not recognize any subspecies of P. olfersii.[13][25] However, other sources recognize the following three subspecies, including the nominotypical subspecies:[9][3][26]

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

References

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  1. ^ a b c d Nogueira C, Gonzales L, Gagliardi G, Schargel W, Rivas G (2019). "Philodryas olfersii ". The IUCN Red List of Threatened Species 2019: https://dx.doi.org/10.2305/IUCN.UK.2019-3.RLTS.T15181934A15181944.en. Accessed on 14 January 2022.
  2. ^ a b c 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).
  3. ^ a b c d Philodryas olfersii. Archived 2013-12-27 at the Wayback Machine The Reptile Database.
  4. ^ a b c O'Shea M (2008). Venomous Snakes of the World. New Holland Publishers. pg. 53.
  5. ^ a b 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.
  6. ^ a b c Sazima I, Marques OAV (2007). "A reliable customer: Hunting site fidelity by an actively foraging neotropical colubrid snake". Archived 2013-12-27 at the Wayback Machine Herpetological Bulletin (99): 36–38.
  7. ^ a b c d e Barbo FE, et al. (2011). "Diversity, natural history, and distribution of snakes in the municipality of São Paulo". Archived 2021-10-25 at the Wayback Machine South American Journal of Herpetology 6 (3): 135–160.
  8. ^ 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).
  9. ^ a b c 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)". Archived 2013-12-27 at the Wayback Machine Herpetozoa 12 (1/2): 11–16.
  10. ^ a b c Correia JM, et al. (2010). "Poisoning due to Philodryas olfersii (Lichtenstein, 1823) attended at Restauração Hospital in Recife, State of Pernambuco, Brazil: Case report". Archived 2017-03-30 at the Wayback Machine Revista da Sociedade Brasileira de Medicina Tropical 43 (3): 336–338.
  11. ^ a b 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. ^ a b 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).
  14. ^ Dourado de Mesquita PCM, et al. (2013). "Reproductive biology of Philodryas olfersii (Serpentes, Dipsadidae) in a subtropical region of Brazil". Archived 2018-12-15 at the Wayback Machine The Herpetological Journal 23 (1): 39–44.
  15. ^ a b c Araújo ME, Santos AC (1997). "Cases of human envenoming caused by Philodryas olfersii and Philodryas patagoniensis (Serpentes: Colubridae)". Archived 2017-12-03 at the Wayback Machine Rev. Soc. Bras. Med. Trop. 30 (6): 517–519.
  16. ^ "Archived copy" (PDF). Archived (PDF) from the original on 2018-12-15. Retrieved 2020-11-17.{{cite web}}: CS1 maint: archived copy as title (link)
  17. ^ Araújo, Maria Elisabeth de; Santos, Ana Cristina M. C. A. dos (December 1997). "Cases of human envenoming caused by Philodryas olfersii and Philodryas patagoniensis (serpentes: Colubridae)". Revista da Sociedade Brasileira de Medicina Tropical. 30 (6): 517–519. doi:10.1590/S0037-86821997000600013. ISSN 0037-8682. PMID 9428185.
  18. ^ Rodríguez-Acosta, Alexis; Lemoine, Karel; Navarrete, Luis; Girón, María E.; Aguilar, Irma (April 2006). "Experimental ophitoxemia produced by the opisthoglyphous lora snake (Philodryas olfersii) venom". Revista da Sociedade Brasileira de Medicina Tropical. 39 (2): 193–197. doi:10.1590/S0037-86822006000200012. ISSN 0037-8682. PMID 16699649.
  19. ^ Ribeiro LA, et al. (1999). "Bites by the colubrid snake Philodryas olfersii: A clinical and epidemiological study of 43 cases". Archived 2018-12-15 at the Wayback Machine Toxicon 37 (6): 943–948.
  20. ^ a b 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". Archived 2014-08-19 at the Wayback Machine Biocell 27 (3): 363–370.
  21. ^ 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.
  22. ^ Vasconcelos, Rebeca Horn (2015). "Alterações dermatomorfológicas de camundongos inoculados com o veneno total da serpente Philodryas nattereri (Dipsadidae)" (PDF). Archived (PDF) from the original on 2021-10-02. Retrieved 2021-10-02. Masters dissertation. (in Portuguese).
  23. ^ da Rocha, Marisa M. T.; Furtado, Maria de F. D. (2007). "Análise das atividades biológicas dos venenos de Philodryas olfersii (Lichtenstein) e P. patagoniensis (Girard) (Serpentes, Colubridae)". Revista Brasileira de Zoologia. 24 (2): 410–418. doi:10.1590/S0101-81752007000200019. Archived from the original on 2021-10-02. Retrieved 2021-10-02.{{cite journal}}: CS1 maint: multiple names: authors list (link) (in Portuguese).
  24. ^ "Acidente com Cobra Verde ENTREVISTA | Biólogo Henrique o Biólogo das Cobras ". Archived from the original on 2021-10-02. Retrieved 2021-10-02 – via www.youtube.com. (in Portuguese).
  25. ^ "Philodryas olfersii ". ITIS (Integrated Taxonomic Information System). www.itis.gov.
  26. ^ "Philodryas olfersii ". Dahms Tierleben. www.dahmstierleben.de/systematik/Reptilien/Squamata/Serpentes/colubroidea/colubridae/dipsadinae#section-58.

Further reading

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  • 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).
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