Philodryas nattereri, also known commonly as the Paraguay green racer and the Paraguayan green racer, is a species of venomous snake in the subfamily Dipsadinae of the family Colubridae. The species is native to eastern South America.
Etymology The specific name, nattereri, is in honor of Austrian naturalist Johann Natterer.
Description Adults of Philodryas nattereri have an average total length (tail included) of , but it can grow to a maximum total length of . It is characterized by a medium body, a long, slender tail, a slightly prominent and obliquely truncated snout, and moderately large eyes with round pupils. Its coloring varies from brown to gray, giving it camouflage against ground foliage.
Behavior Philodryas nattereri is a fast snake with terrestrial habits, although recent studies have shown that this species can use arboreal environments with high efficiency. It is active during the day and can be quite aggressive when threatened. P. nattereri is opisthoglyphous (rear-fanged), and due to this dentition, it has difficulty injecting venom into large prey. Thesis for Doctor of Pharmacology. Universidade Federal do Ceará, Fortaleza, Ceará, Brazil. (in Portuguese, with an abstract in English).
Geographic distribution Philodryas nattereri is found in eastern Brazil and Paraguay.
Habitat The preferred natural habitats of Philodryas nattereri are open forests, fields and cerrado.
Diet Philodryas nattereri feeds on a wide variety of prey, including birds, mammals, lizards, amphibians, lizard eggs and even other snakes.
Reproduction Philodryas nattereri is oviparous. www.reptile-database.org.
Venom The venom of Philodryas nattereri is quite active. It can cause dermo necrosis, myonecrosis, and hemorrhagic activity, resulting in mast cell degranulation, muscle damage and inflammation. Studies with rats have shown that venom from this species is capable of causing bleeding in different organs and morphological alterations. (in Portuguese, with an abstract in English). The venom of this species appears to be as active as that of Philodryas olfersii, and has a protein content of 863.9 μg, which corresponds to 86.3% of the entire venom. Dissertation for Master of Veterinary Science. Universidade Estadual do Ceará. Fortaleza, Ceará, Brazil. (in Portuguese. with an abstract in English).
References
Further reading xiv + 727 pp. + Plates I–XXV. (Philodryas nattereri, p. 134). 189 pp. (Philodryas nattereri, p. 106).
+ Plates I–VIII. (Philodryas nattereri, new species, p. 345 + Plate VII, figures 1–3, three views of head and neck). (in German).