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Home/Species/ Sonoran Whipsnake

Masticophis bilineatus

Jan, 1867

Sonoran Whipsnake

G5Secure Found in 25 roadless areas NatureServe Explorer →
G5SecureGlobal Rank
Least concernIUCN
LowThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.104217
Element CodeARADB21010
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVertebrate Animal
IUCNLeast concern
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomAnimalia
PhylumCraniata
ClassReptilia
OrderSquamata
FamilyColubridae
GenusMasticophis
Synonyms
Coluber bilineatus(Jan, 1863)
Concept Reference
Camper, J. D. 1996. Masticophis bilineatus. Catalogue of American Amphibians and Reptiles 637.1-637.4.
Taxonomic Comments
Nicholson (2025) is following Myers et al. (2017) in recognizing Masticophis as a genus. In addition, the date of publication has been corrected; the specific name M. bilineatum was introduced by Jan (1863) as a nomen nudum, and was formally published by Jan (in Jan and Sordelli, 1867) (Nicholson 2025).
Conservation Status
Review Date2005-12-05
Change Date1996-10-30
Edition Date2005-12-05
Edition AuthorsHammerson, G.
Threat ImpactLow
Range Extent200,000-2,500,000 square km (about 80,000-1,000,000 square miles)
Number of Occurrences81 - 300
Range Extent Comments
The range extends from central Arizona to extreme southwestern New Mexico and south through western Mexico to Colima, Mexico, with an eastward extension onto the Mexican Plateau in Jalisco, Aguascalientes, and Zacatecas (Camper and Dixon 1994, Camper 1996). Camper and Dixon regarded records from Isla San Pedro Martir, Coahuila, and Oaxaca as erroneous. Elevational range extends to 2,300 meters (Camper 1996).
Occurrences Comments
This species is represented by a large number of occurrences or subpopulations. Camper (1996) mapped over 200 collection sites.
Threat Impact Comments
No major threats are known. The habitat often is unsuitable for most incompatible human uses.
Ecology & Habitat

Habitat

Habitats include semiarid lower mountain slopes, with growth of grass, saguaro cactus, paloverde, and ocotillo, and extend through chaparral and juniper into pine-oak belt in mountains (Stebbins 2003); desert, grassland, and montane forest habitats (Camper 1996), often found along rocky streams. This snake is basically terrestrial but also climbs in vegetation.

Reproduction

Lays a clutch of 6-13 eggs, June-July (Stebbins 1985).
Terrestrial Habitats
Woodland - ConiferWoodland - MixedShrubland/chaparralDesertBare rock/talus/scree
Palustrine Habitats
Riparian
Other Nations (1)
United StatesN5
ProvinceRankNative
New MexicoS3Yes
ArizonaS5Yes
Roadless Areas (25)
Arizona (24)
AreaForestAcres
Arnold MesaPrescott National Forest12,286
BoulderTonto National Forest40,359
Butterfly Roadless AreaCoronado National Forest42,296
Catalina St. Pk. Roadless AreaCoronado National Forest951
ChiricahuaCoronado National Forest76,876
GaliuroCoronado National Forest28,333
GoldfieldTonto National Forest15,257
Grief HillPrescott National Forest12,535
Happy ValleyCoronado National Forest7,972
HellsgateTonto National Forest6,171
Lime CreekTonto National Forest42,568
Lower RinconCoronado National Forest3,278
Middle Dragoon RoadlessCoronado National Forest10,543
Middle Romero WSRCoronado National Forest60
Oracle RoadlessCoronado National Forest22,365
PicachoTonto National Forest4,969
PinalenoCoronado National Forest130,920
Santa TeresaCoronado National Forest8,929
Sierra Ancha Wilderness ContiguousTonto National Forest7,787
TumacacoriCoronado National Forest44,594
Upper Dragoon RoadlessCoronado National Forest2,533
Upper Rincon RoadlessCoronado National Forest2,991
Upper Romero WsrCoronado National Forest150
WhetstoneCoronado National Forest20,728
New Mexico (1)
AreaForestAcres
Peloncillo (NM)Coronado National Forest43,339
References (18)
  1. Behler, J. L., and F. W. King. 1979. The Audubon Society field guide to North American reptiles and amphibians. Alfred A. Knopf, New York. 719 pp.
  2. Camper, J. D. 1996. <i>Masticophis bilineatus</i>. Catalogue of American Amphibians and Reptiles 637.1-637.4.
  3. Camper, J. D., and J. R. Dixon. 1994. Geographic variation and systematics of the striped whipsnakes (<i>Masticophis taeniatus</i> complex; Reptilia: Serpentes: Colubridae). Annals of Carnegie Museum 63(1):1-48.
  4. Collins, J. T. 1990. Standard common and current scientific names for North American amphibians and reptiles. 3rd ed. Society for the Study of Amphibians and Reptiles. Herpetological Circular No. 19. 41 pp.
  5. Collins, J. T. 1991. Viewpoint: a new taxonomic arrangement for some North American amphibians and reptiles. SSAR Herpetol. Review 22:42-43.
  6. Collins, J. T. 1997. Standard common and current scientific names for North American amphibians and reptiles. Fourth edition. Society for the Study of Amphibians and Reptiles, Herpetological Circular No. 25. 40 pp.
  7. Conant, R., and J. T. Collins. 1998. A field guide to reptiles and amphibians: eastern and central North America. Third edition, expanded. Houghton Mifflin Co., Boston, Massachusetts. 616 pp.
  8. Crother, B. I. (editor). 2012. Scientific and standard English names of amphibians and reptiles of North America north of Mexico, with comments regarding confidence in our understanding. 7th edition. SSAR Herpetological Circular 39:1-92.
  9. Crother, B. I. (editor). 2017. Scientific and standard English names of amphibians and reptiles of North America north of Mexico, with comments regarding confidence in our understanding. 8th edition. SSAR Herpetological Circular 43:1-104. [Updates in SSAR North American Species Names Database at: https://ssarherps.org/cndb]
  10. Degenhardt, W. G., C. W. Painter, and A. H. Price. 1996. Amphibians and reptiles of New Mexico. University of New Mexico Press, Albuquerque. xix + 431 pp.
  11. Dowling, H. G. 1993. Viewpoint: a reply to Collins (1991, 1992). Herpetol. Rev. 24:11-13.
  12. Myers, E. A., J. L. Burgoon, J. M. Ray, J. E. Martínez-Gómez, N. Matías-Ferrer, D. G. Mulcahy, F. T. Burbrink. 2017. Coalescent Species Tree Inference of <i>Coluber </i>and <i>Masticophis</i>. Copeia 105(4):640-648.
  13. Nagy, Z. T., R. Lawson, U. Joger, and M. Wink. 2004. Molecular systematics of racers, whipsnakes and relatives (Reptilia: Colubridae) using mitochondrial and nuclear markers. Journal of Zoological Systematics and Evolutionary Research 42(3):223-233.
  14. Nicholson, K. E. (ed.). 2025. Scientific and Standard English Names of Amphibians and Reptiles of North America North of Mexico, with Comments Regarding Confidence in Our Understanding. Ninth Edition. Society for the Study of Amphibians and Reptiles. 87pp. Online database available at: https://cnah.org/SSARnames.aspx
  15. Pyron, R. A., F. T. Burbrink, and J. J. Wiens. 2013. A phylogeny and revised classification of Squamata, including 4161 species of lizards and snakes. BMC Evolutionary Biology 29:131.
  16. Stebbins, R. C. 1985a. A field guide to western reptiles and amphibians. Second edition. Houghton Mifflin Company, Boston, Massachusetts. xiv + 336 pp.
  17. Stebbins, R. C. 2003. A field guide to western reptiles and amphibians. Third edition. Houghton Mifflin Company, Boston.
  18. Utiger, U., B. Schätti, and N. Helfenberger. 2005. The Oriental colubrine genus <i>Coelognathus </i>Fitzinger, 1843, and classification of old and new world racers and ratsnakes (Reptilia, Squamata, Colubridae, Colubrinae). Russian Journal of Herpetology 12(1):39-60.