Southern Durango spotted garter snake explained

The Southern Durango spotted garter snake (Thamnophis nigronuchalis) is a species of snake of the family Colubridae. It is endemic to the state of Durango, Mexico.

Description

This is a heavy-bodied, medium sized garter snake. It has an oval-shaped head with two supralabial scales, two preocular scales, and a distinct black blotch on the dorsal surface of its neck. It has 149-165 ventral and 63-70 caudal scales. Ventral scales are heavily pigmented, often forming an irregular black stripe. The dorsal pattern consists of rufous-colored spots outlined in black in 5-10 rows, with no dorsal or lateral stripes.[1]

Taxonomy

Classification

While it is now considered a valid species,[2] some authorities have classified this snake as a subspecies of the narrow-headed garter snake under the name Thamnophis rufipunctatus nigronuchalis.[3]

Etymology

The specific name nigronuchalis references the Latin word nigro meaning black, and nuchal meaning of the nape, and is derived from the black neck patch characteristic of the species.[1]

Distribution and habitat

This snake is endemic to Durango state in Mexico,[4] where it is found in wet meadows and riparian areas at altitudes of 8500–9000 feet.[1] It appears to be restricted to high elevation drainage basins of the Sierra Madre Occidental.[5]

Diet

This species has been documented to eat earthworms and amphibians, including Rana pipiens and Hyla species.[1]

Notes and References

  1. Thompson . Fred G . A New Mexican Gartersnake (Genus Thamnophis) With Notes On Related Forms . Occasional Papers of the Museum of Zoology . 22 March 1957 . 584 . 1–10 . 6 May 2020.
  2. Web site: ITIS Standard Report Page: Thamnophis nigronuchalis . Integrated Taxonomic Information System . 6 May 2020.
  3. Tanner . William W . Thamnophis rufipunctatus . Catalog of American Amphibians and Reptiles (CAAR) . 31 July 1990 . 6 May 2020.
  4. Lemos-Espinal . Julio A. . Smith . Geoffrey R. . Gadsden-Esparza . Hector . Valdez-Lares . Rosaura . Woolrich-Piña . Guillermo A. . Amphibians and reptiles of the state of Durango, Mexico, with comparisons with adjoining states . ZooKeys . 4 April 2018 . 748 . 65–87 . 29674915. 10.3897/zookeys.748.22768 . 5904398 . free .
  5. Book: Rossman . Douglas A . Ford . Neil B . Seigal . Richard A . The Garter Snakes: Evolution and Ecology . 1996 . University of Oklahoma Press . Norman, Oklahoma . 0806128208 . 216–218.