''Dipsas williamsi'', also known commonly as Williams's tree snake, is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of non

venomous Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a sti ...

snake Snakes are elongated, Limbless vertebrate, limbless, carnivore, carnivorous reptiles of the suborder Serpentes . Like all other Squamata, squamates, snakes are ectothermic, amniote vertebrates covered in overlapping Scale (zoology), scales. Ma ...

in the

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end subfamily botanical names with "-oideae", and zoologi ...

Dipsadinae Dipsadinae is a large subfamily of colubroid snakes, sometimes referred to as a family (Dipsadidae). They are found in most of the Americas, including the West Indies, and are most diverse in South America. There are more than 700 species. Dips ...

of the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Colubridae Colubridae (, commonly known as colubrids , from la, coluber, 'snake') is a family of snakes. With 249 genera, it is the largest snake family. The earliest species of the family date back to the Oligocene epoch. Colubrid snakes are found on ever ...

. The species is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = Seal (emblem), National seal , national_motto = "Fi ...

. It was named in honor of

Ernest Edward Williams Ernest Edward Williams (January 7, 1914 – September 1, 1998) was an American herpetologist. He coined the term ''ecomorph'' based on his research on anoles. Taxa named in honor of Ernest E. Williams The following species are named in honor of ...

by Nelly Carrillo Espinoza (1974).

Original publication

* Carrillo de Espinoza N (1974). "''Sibynomorphus williamsi nov. sp. (Serpentes: Colubridae)''". ''Publicaciones del Museo de Historia Natural “Javier Prado”, Serie A (Zoología)'' (24): 1–16. (''Sibynomorphus wiiliamsi'', new species). (in Spanish).

References

Dipsas Snakes of South America Reptiles of Peru Endemic fauna of Peru Reptiles described in 1974 {{Dipsadinae-stub