Introduction
Ensatina eschscholtzii are a glossy, sometimes rather colorful species found throughout western U.S. and lower British Columbia. The body is somewhat robust, with long limbs, and thick tails with a prominent constriction near the base. It is at the constriction that the tail autotomizes when necessary to distract potential predators. 

Subspecies range in size from 2.95-6.10 inches in total length, and increase in size from north to south, with the exception of the rather small E. e. picta. Males can be differentiated from females by their more truncated snouts, swollen cloaca, and enlarged upper lip Stebbins, 2003). Males also possess longer, more slender tails than females. Significance of size between males and females is unknown. There are approximately seven recognized subspecies, and several intergrade zones. 

Although E. eschscholtzii is generally treated as a "ring species", with seven subspecies, studies have shown limited gene exchange between many of the subspecies, indicating the likelihood of species level classification of some of some in the near future. It is hypothesized that the genus Ensatina is comprised of two or more species that form a superspecies complex. Another hypothesis states that the Ensatina complex is a "double ring species", with two zones where overlapping subspecies display little or no gene exchange (Petranka, 1998). However, for now, and until further data proves otherwise, E. eschscholtzii will be treated as one, polytypic species, with the traditional seven subspecies. In general, there are blotched subspecies found in the southern and eastern sides of the Great Central Valley, while the coastal and northwestern subspecies are un-blotched. The following briefly describes the different subspecies:

Subspecies

  
E. e. eschscholtzii, photos © Gary Nafis, California Reptiles and Amphibians | more photos of Ensatina eschscholtzii

E. e. xanthoptica (Stebbins, 1949) Yellow Eyed Ensatina
E. e. xanthoptica are dark to moderately dark brown dorsally, with yellow-orange colored bellies. This subspecies possesses distinct yellow coloration about the sub- and super-ocular areas, as well as a distinct yellow patch in the eye. The yellow eye coloration, in addition to the brown dorsum and lighter colored belly is thought to be mimicry of sympatric Tarichids, the toxic newts of the genus Taricha. Juveniles are darker colored dorsally, with bright yellow-orange coloration at the bases of the limbs, and often a similar colored tail. This subspecies is found from Sonoma Co., Calif. to Merced Co., and Santa Cruz Co (Stebbins, 2003). E. e. xanthoptica hybridize with E. e. eschscholtzii where their ranges overlap. Populations are also found on the inland side of the ring, where they rarely hybridize with E. e. platensis.

E. e. oregonensis (Girard, 1856) Oregon Ensatina
In some texts this subspecies is only recognized as a morphotype, that is, a morpholocially distinct group that may be out of synchrony with molecular findings (Stebbins, 2003). This form is light to moderately dark brown dorsally, with a lighter colored, speckled or mottled belly. Flecks of white or pale orange are often found on the dorsum. The sides are orange or yellow, sometimes with lighter colored mottling concentrated about the costal grooves. Yellow-orange coloration is found on the proximal portions of all four limbs. Petranka (1998) shows distribution from southwestern Canada, south along the Washington and Oregon coasts, and into northwestern California coastal areas. Stebbins (2003) has excluded the California distribution, and instead provides an unknown intergrade range in place. E. e. oregonensis is thought to intergrade with E. e. eschscholtzii in the San Francisco Bay area, and with E. e. platensis in the northern Sierra Foothills, however, the exact range of the intergrade zones are questionable.

E. e. picta (Girard, 1856) Painted Ensatina
This is a smaller subspecies, approximately 2/3 the size of the nominate form (Stebbins, 2003). E. e. picta are light to dark brown dorsally, with black or yellow-orange blotching that extends onto the tail, although some may lack any blotching. In the intergrade zone with E. e. platensis, spot size is diminished in a narrow zone, and from here forward, spot size increases into the large, brightly colored blotches characteristic of E. e. platensis, with some plain colored individuals dispersed about the entire intergrade zone (Stebbins, 2003; Petranka, 1998; Brown). E. e. picta have a small range that includes extreme northwestern California, into extreme southwestern Oregon. E. e. picta intergrade with E. e. oregonensis in California.

E. e. platensis (Espada, 1875) Sierra Nevada Ensatina
This is a very colorful subspecies, usually blotched with bright orange, reddish, or yellow about the head, body, limbs, and tail. Blotching varies in size and abundance from small flecks, to nearly solid colored individuals. The ventral surface is whitish-cream to pale gray colored. Juveniles are darker colored, with reduced blotching on the dorsal surface. Bright coloration is found on the proximal portions of all four limbs. This subspecies is found throughout the Sierra Nevada foothills of California, to the Greenhorn Mountains, southeast of Bakersfield (Stebbins, 2003; Brown). In the north, E. e. platensis intergrades with E. e. oregonensis, and in the south with E. e. croceater.  

E. e. croceater (Cope, 1867) Yellow Blotched Ensatina
This subspecies possesses blotching of large, yellow, orangish, or cream colored markings about the dorsum, head, tail, and legs, on a black or dark gray background. Spots are typically large, and either connected, or clearly differentiated, as opposed to E. e. platensis, which may appear densely mottled with varying sized spots. The ventral surface is pale cream colored to light gray. Bright coloration is found on the proximal portions of all four limbs E. e. croceater are found in the Tehachapi Mts., Pinos, vicinity of Fort Tejon, and the Frazier-Alamo Mt. area, California (Stebbins, 2003). Intergrades of E. e. croceater and E. e. platensis are occur in the southern range of E. e. platensis and the northern range of E. e. croceater. This subspecies also intergrades with E. e. klauberi.

E. e. klauberi (Dunn, 1929) Large Blotched Ensatina
In some texts, E. e. klauberi is considered a full species, Ensatina klauberi. Like E. e. croceater, E. e. klauberi possess large blotches of orange, white, or yellow, over a black background. The spots are often connected, and create diagonal, or transverse bands about the dorsum and tail (Petranka, 1998). The ventral surface is dark gray. Bright coloration is found on the proximal portions of all four limbs. E. e. klauberi intergrade with E. e. croceater in the San Bernardino Mountains, and rarely with E. e. eschscholtzii in southern ranges. 

Distribution & Integration Patterns

In the near future, it is likely that molecular data will divide E. eschscholtzii into two or more species. For now, and until present studies are completed, Ensatina eschscholtzii is regarded as a polytypic species; a semispecies complex that portrays a typical example of the Darwinian gradualism, where multiple micro-mutations have lead to the formation of several subspecies/species (Brown).  

Habits & Habitats

Adults and juveniles are most active during wet weather, when they can be found on the surface in abundance. Adults go back into hiding during the egg laying period, but juveniles may remain on the surface until the onset of drier, warmer weather (Petranka, 1998). Ensatina do not create their burrows, but occupy abandoned holes, root channels, and other micro-channels that allow them to escape the dry surface. Adults may reside as deep as 90 cm below the surface during the summer. At the time of emergence, in autumn, adults and juveniles may be depleted of food reserves after their summer aestivation. 

Males are territorial outside of the breeding season, and do not tolerate other males within their summer residences. Females are less territorial than males. Individuals are thought to mark their territory with feces or chemical secretions. 

Humboldt Co., habitat of E. e. oregonensis. Photo © Gary Nafis, California Reptiles and Amphibians

Lifecycle

Courtship consists of the male creeping up to the female, and nudging the sides of her head, face, and throat with his head and neck. The male then moves into a position such that his hip region is just under the females chin. The male will rub the hip region about the females throat by rotating hip movements. The male will then attempt to lead the female off, while keeping the back in an arched position. A stimulated female will press her throat against the males hip region, and follow his lead, while straddling his tail. This stage of courtship may last for several hours (Petranka, 1998). 

After a suitable time, the male stops and deposits a spermatophore onto the substrate, while the female strokes his sacral (hip) region with her throat. After a short while, the female lifts her head, and the two move forward until the spermatophore is aligned with the females vent. The female collects the spermatophore by squatting down onto it. At the same time, the male moves back a bit, positions his tail over the females back, and flicks it to and forth. At this point, courtship has ended, however, a pair may begin courting again a few moments later (Petranka, 1998).

Females of southern and central populations deposit eggs in late spring, while northern coastal and higher elevation Sierra Nevada populations deposit in early summer. Oviposition requires a day, during which the female may lay on her side or back (Petranka, 1998). Five to twenty-five eggs are deposited in disconnected clumps, in moist hiding spots, typically under logs, moss-mats, or underground. Late semester embryos possess leaf-like, vascularized gills. Clutch size is proportional to the females size, and the incubation period lasts anywhere from 4-5 months (Petranka, 1998). Females will remain and guard their clutches to hatching.

Juveniles grow quickly for the first few years of life, and slow down drastically as they near sexual maturity. 

E. e. oregonensis, photos © Suzanne L. Collins, Center for North American Herpetology | more photos of Ensatina eschscholtzii

Defense Method

If further provoked, Ensatina may autotomize their writhing tails, in an attempt to distract a potential predator. This may give the salamander a moment to sneak away. The tail is constricted at the base, which marks the spot of separation. Tail regeneration may take up to two years. Tail autotomization may cause the salamander hardship in the future, especially during aestivation, as it is an important storage reserve.

The mottled coloration and pattern of some is thought to be a form of cryptic coloration related to soil color. The mottled forms typically possess bright coloration specifically on the proximal portions of the limbs and the dorsum, which may have the effect of breaking up the salamanders silhouette against certain backgrounds. Juveniles and adults of the non-blotched forms often possess the same coloration about the proximal areas of the limbs. 

As mentioned earlier, some coastal populations are thought to be mimics of toxic newts of the genus Taricha. This is especially noticeable in E. e. xanthoptica, which possess light yellowish coloration about the snout, subocular, and superocular areas, as well as a distinct yellow patch in the eye. This yellow coloration, in addition to the dark to medium brown dorsum, is remarkably similar to some Tarichids.

E. e. platensis defense posture, photo © Gary Nafis, California Reptiles and Amphibians | more photos of Ensatina eschscholtzii

E. e. eschscholtzii with noxious secretions, photo © Gary Nafis, California Reptiles and Amphibians | more photos of Ensatina eschscholtzii