Western Milk Snake

Ophibolus doliatus variety gentilis, (B. & G.)

Colouration: Red bands above, more broadly bordered with black than existing with the other varieties of doliatus already described, the black usually encircling the body as pairs of rings; between these rings is a narrow area of yellow.
Dimensions: This is a slightly larger reptile than the typical form, though of the same conformation. An adult specimen will measure about 28 inches.
Distribution: Nebraska and western Louisiana to south-western Texas and northern Mexico.

In the consideration of this variety, we observe another phase of variation away from the ancestral form. While the preceding varieties have inclined toward a constriction of the red blotches, thus presenting a more spotted appearance than the typical form, the trend of variation with the succeeding forms is quite in the opposite direction--that is, the red areas are inclined to widen and their black borders to extend around the body as rings, producing much the same effect as the pattern of the venomous coral snakes (Elaps), hence these reptiles are among those serpents that "mimic" the poisonous colubrine snakes.

The status of the present variety is somewhat doubtful. It is the Western representative of the ancestral form, and extends well within the Western range of the latter. Some specimens are symmetrically ringed with the black; others have large black blotches on the abdomen beneath the red areas. It is possible that these differences should be recognised under distinct, varietal names, yet the confusing, intergrading forms cause one to hesitate before adopting such a course. Technical workers have much to do in solving this problem, one way or the other.

The Mexican Ringed King Snakes, recognised specifically under the technical head of annulatus or micropholis, are very closely allied to the present variety. An elaborate series of specimens might prove the array of forms extending through Mexico and Central America, to be simply a chain of varieties connecting with the North American forms.

On many specimens, the space on the abdomen directly beneath the red is entirely suffused with black, the red extending downward to the abdominal plates. Both from above and from the side, such a specimen presents a ringed appearance. Above, the larger areas are rich scarlet.

On occasional specimens the black rings fuse into a smoky band along the back.

The entire top of the head is usually black with the exception of the snout, which is red.

As this is a very variable form, numerous specimens may be found that will greatly confuse the student in separating it from doliatus. The tendency of the black to form rings about the body; the extension of the red to the abdominal plates and the consequent absence of a black-bordered, saddle-like pattern are the most important points of discrimination. Besides these characters, it should be noted that there are no smaller, alternating blotches on the sides.