<img src="https://d5nxst8fruw4z.cloudfront.net/atrk.gif?account=iA1Pi1a8Dy00ym" style="display:none" height="1" width="1" alt="" />
Skip Navigation
Our Terms of Use (click here to view) have changed. By continuing to use this site, you are agreeing to our new Terms of Use.

14.1: Crotalus ruber: Red Diamond Rattlesnake

Difficulty Level: At Grade Created by: CK-12
Turn In

Common Name

  • Red Diamond Rattlesnake
  • Credos Island Rattlesnake
  • San Lorenzo Island Rattlesnake
  • San Lucan Rattlesnake


Crotalus rubber, the red diamond rattlesnake, is three to five feet long with reddish-brown scales and vague white diamonds crisscrossing the back. At the end of the tail is a rattle, used to warn and signal its existence to anything that could stand out as a threat.

The complete taxonomic classification is:

  • Kingdom: Animalia
  • Phylum: Chordata
  • Class: Reptilia
  • Order: Squamata
  • Family: Viperidae
  • Genus: Crotalus
  • Species: C. ruber


The range of this species can be found in southwestern California and throughout the Baja California peninsula. It also lives on some islands in the California Gulf. It often inhabits and rests inside rock outcrops. C. ruber can be found in desert scrub, coastal sage scrub, mesquite cactus and pine or oak forests.


Cell Biology

Like all reptiles, C. ruber has eukaryotic cells, which have many organelles, and are found in all plants, animals, and even fungi. Examples of these organelles are the nucleus, vacuoles and vesicles. Another organelle called the mitochondria provides energy needed to power chemical reactions. An example of an organelle that is very important is called the ribosomes, where proteins are made. The part of the cell that takes care of waste is known as the lysosome. Endoplasmic reticulum is a folded membrane that transports proteins.

Cells multiply through mitosis, or when the nucleus divides, and each new cell contains a copy of the DNA in the cell before it. Another way cells multiply is through meiosis for reproduction. In meiosis, the cell divides to make gametes, with half the chromosomes of the parent cell. C. ruber has red blood cells, which transport oxygen around the body, and nerve cells, among other specialized cells.


The earliest reptiles, or amniotes, evolved around 350,000,000 years ago. Then 30 million years later is when they would separate into two groups, synapsids and sauropsids. Ancestors of modern snakes were sauropsids.


C. ruber is hunted by birds of prey like hawks. It uses scrub and cactus for shelter and will also hide in rock outcrops. C. ruber mates in spring, delivering three to twenty young in summer. Its diet consists mainly of small rodents. Examples are woodrats, small birds, rabbits, other reptiles and ground squirrels. Also, ground squirrels are immune to the snake’s venom, and they will attack threatening rattlesnakes.

Anatomy and Physiology

C. ruber is cold blooded, which means it relies on the environment to control its body temperature. They have scales covering the entire body. C. ruber has a forked tongue used for smelling. The snake will hunt at night with pit organs that allow for thermal vision. Another set of organs, called Jacobson’s organs, are connected to the nose and let the snake “taste” the air. Even after death, this snake should still be treated as a dangerous threat, due to neurological reflexes that allow the snake to bite. The venom, which is a complicated mixture of proteins that affects blood tissue, can be fatal. The rattle is made of keratin. During each shedding, a new segment is added to the rattle. Depending on how much the snake sheds, rattles can vary in size.


This snake is normally non-aggressive and solitary (except during mating season). C. ruber will normally not attack unless it is disturbed. It is sometimes territorial, and it is very active during mating season (spring to summer). It hunts mostly at night and is more social in cold temperatures.




  • Finn J. Morton

Supervising Faculty

  • Amy Huff Shah


  • Museum School, San Diego, California


  • Published prior to review.

Edit History

  • Created: April 5, 2013
  • Version 1.0 submitted to CK-12: July 4, 2013
  • CK-12 edits: in progress


  • Middle School (grades 6-8)

Notes/Highlights Having trouble? Report an issue.

Color Highlighted Text Notes
Please to create your own Highlights / Notes
Show More

Image Attributions

Show Hide Details
6 , 7 , 8 , 9 , 10 , 11 , 12
Date Created:
Jul 08, 2013
Last Modified:
Jan 30, 2016
Save or share your relevant files like activites, homework and worksheet.
To add resources, you must be the owner of the section. Click Customize to make your own copy.
Please wait...
Please wait...
Image Detail
Sizes: Medium | Original