Order:  Squamata
Serpentes: (Snakes)

The following taxonomic list will link you to the individual species.

Snakes have several unique characteristics that should allow you to readily identify them as members of the group Serpentes.  All snakes lack limbs; there are however, some species that have vestigialClick word for definition limbs in the form of small spurs.  All snakes lack eyelids (there are some lizard species that lack eyelids, but none in Idaho).  Snakes have no external ear opening (some burrowing lizards lack ear openings as well, but all Idaho lizard species have an external ear opening).  Finally, snakes have a elongate body.  Again, there are some lizard species that are limbless and have long slender bodies, but none of these species occur in Idaho.

Family:  Boidae

The family Boidae includes the largest living snakes, but the Idaho representative of this family, the Rubber Boa (Charina bottae) is very modest in size.  The 20 genera (Pough et al. 1998) that comprise this family occupy a wide range of habitats and come in a wide range of forms.  There is also variety in the reproductive modes of species within this family.  The pythons (subfamily Pythoninae) are oviparousClick word for definition (egg laying), while boas (subfamily Boinae) are viviparousClick word for definition (live birth), this includes the native Rubber Boa.  A feature common among boas and pythons is the presence of a vestigialClick word for definition pelvic girdle and pelvic spurs, which are remnants of hind limb bones (Goin and Goin 1971).  Once again, the Idaho representative of this family does indeed display this trait.


Family:  Colubridae

The family Colubridae is the largest snake family, containing approximately 70 percent of all snake species (Pough et al. 1998).  This wide range of diversity makes it difficult to describe any family characteristics that hold true for all members of the family.  Members of this family are found worldwide, they vary in reproductive mode, having both oviparousClick word for definition and viviparousClick word for definition species, and they occupy a wide variety of habitats.  The bulk of Idaho's snake species are from this family and they display the diversity that is characteristic of the family.  The Idaho representatives of this family include the Racer (Coluber constrictor), Ringneck Snake (Diadophis punctatus), Night Snake (Hypsiglena torquata), Striped Whipsnake (Masticophis taeniatus), Gopher Snake (Pituophis catenifer), Longnose Snake (Rhinocheilus lecontei), Western Ground Snake (Sonora semiannulata), Western Terrestrial Garter Snake (Thamnophis elegans) and the Common Garter Snake (Thamnophis sirtalis).
Coluber constrictor
Diadophis punctatus
(Ringneck Snake)
Hypsiglena torquata
(Night Snake)
Masticophis taeniatus
(Striped Whipsnake)
Pituophis catenifer
(Gopher Snake)
Rhinocheilus lecontei
(Longnose Snake)
Sonora semiannulata
(Ground Snake)
Thamnophis elegans
(Western Terrestrial Garter Snake)
Thamnophis sirtalis
(Common Garter Snake)

Family: Viperidae

The family Viperidae contains venomous species ranging from the readily recognizable rattlesnakes to the vipers of the old world.  The envenomation mechanism of members of this family are at the highest form of development (Goin and Goin 1971).  The fangs are hollow and connected to venom glands to allow the injection of venom when biting.  When the mouth is closed, the long fangs are folded up towards the roof of the mouth.  When Vipers strike, their fangs swing foward to puncture the target and allow envenomation.  The family contains 20-27 genera that are distributed across North, Central and South America, eastern Asia, Africa, and Eurasia (Pough et al. 1998).  The Idaho representative of this family is the Western Rattlesnake (Crotalus viridis).


Author: John Cossel Jr.© 1997
Design and Optimization by Ean Harker©1999, 2000.
Adaptation for DAI by Stephen Burton, and Mike Legler ©1999.
Original images provided by Charles R. Peterson and John Cossel Jr.©1998.