Biologists identify six new unique species of the western rattlesnake

March 4, 2016 by Chris Branam
Biologists identify six new unique species of the western rattlesnake
The great basin rattlesnake (Crotalus lutosus), one of six new unique species identified by University of Arkansas biologists and their colleagues Credit: Blake L. Thomason

There are more species of rattlesnake slithering around western North America than previously thought.

That's the conclusion of a new study conducted by University of Arkansas biologists Michael Douglas and Marlis Douglas and their colleagues at the University of Illinois at Urbana-Champaign and Western Kentucky University.

The researchers published their findings in the journal PLOS One.

The research team, using head shapes and genetic analyses, recommend that six groups of subspecies of the western rattlesnake be elevated to full species status, with the following names:

  • Crotalus viridis, prairie rattlesnake
  • Crotalus oreganus, northern Pacific rattlesnake
  • Crotalus cerberus, Arizona black rattlesnake
  • Crotalus helleri, southern Pacific rattlesnake
  • Crotalus concolor, midget faded rattlesnake
  • Crotalus lutosus, great basin rattlesnake

The scientific and standard English names will be submitted to the International Committee on Zoological Nomenclature for ratification.

The study has important implications for ecological conservation efforts across the United States, said Michael Douglas, professor of biological sciences and Twenty-First Century Chair in Global Change Biology.

"These snakes have been long been recognized by herpetologists as being demonstrably different, and in fact were designated as western rattlesnake subspecies in the first half of the 20th century," Douglas said. "None are currently considered rare, but species designation allows them to gain certain legal protection, particularly within individual states."

Marlis Douglas, associate professor of biological sciences and Bruker Chair of Life Sciences, said the genetic data were also evaluated to identify these snakes as individual species. The Douglases collaborated with Mark Davis, research scientist at the Illinois Natural History Survey, part of the Prairie Research Institute at the University of Illinois, and Michael Collyer, associate professor of biology at Western Kentucky University.

As part of his doctoral research, Davis collected data from nearly 3,000 western rattlesnakes available in natural history museums across the western United States.

In addition to genetic traits, the team examined head shape, which can vary drastically between different of snakes and potentially reflect what kind of prey the snake prefers.

Explore further: Head shape and genetics augment understanding of rattlesnake species

More information: Mark A. Davis et al. Correction: Deconstructing a Species-Complex: Geometric Morphometric and Molecular Analyses Define Species in the Western Rattlesnake (Crotalus viridis), PLOS ONE (2016). DOI: 10.1371/journal.pone.0149712

Related Stories

Mysterious fungus killing snakes in at least nine states

August 9, 2015

Hidden on hillsides in a remote part of western Vermont, a small number of venomous timber rattlesnakes slither among the rocks, but their isolation can't protect them from a mysterious fungus spreading across the eastern ...

Massachusetts plans rattlesnake colony on uninhabited island

February 21, 2016

A plan by the state to establish a colony of venomous timber rattlesnakes on an off-limits island in Massachusetts' largest body of water has some rattled by visions of dangerous serpents slithering through the surrounding ...

Recommended for you

Study shows how giraffe assassin bugs outwit spider prey

October 26, 2016

(—A biologist at Macquarie University in Australia has discovered the secret behind the giraffe assassin's ability to catch and kill spiders in their webs. In his paper published on the open access site Royal Society ...

New analysis of big data sheds light on cell functions

October 26, 2016

Researchers have developed a new way of obtaining useful information from big data in biology to better understand—and predict—what goes on inside a cell. Using genome-scale models, researchers were able to integrate ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.