by Greg Mayer
Matthew sent me the following tw**t from Bryan D. Hughes, the rattlesnakeguy:
Here's a cool picture sent to us by Susan Harnage. It's a longnosed snake with a partial stripe – an error in the pattern. Pretty cool! pic.twitter.com/5Eakop7dcY
— Bryan D. Hughes (@rattlesnakeguy) March 15, 2017
The tw**t doesn’t say where the picture was taken, but I’m guessing somewhere in the American southwest. It does say it’s a longnosed snake (Rhinocheilus lecontei), but it doesn’t look to be one to me. I’m pretty sure it’s a common kingsnake (Lampropeltis getula). [Added later: it is a longnosed– see comment below by rattlesnakeguy.]
The interest in this snake is that it’s banded fore and aft, but striped amidships, which is pretty unusual. The kingsnake is usually banded, but striped ones are known from southern California and Baja– this snake has both! Snakes with unusual and partial patterns are popular amongst herpetoculturalists, and I recall from grad school that one of my cohort working on snake development got stripey patterns from eggs incubated at the wrong temperature. Some quick checking revealed some definite evidence of low temperature incubation leading to striping in pythons (here and here), and some vaguer rumblings in the cornsnake forums, but I could not find any scientific papers on the subject. I did find some more reliable evidence that incubation temperature does not influence pattern in Australian eastern brown snakes.
Snake patterns are thought to have an influence on their detectability and catchability by visual predators; bands are often camouflagey, while stripes tend to make a predator (me!) grab behind the snake, as the longitudinal stripe obscures the forward motion of the snake, and the grab is mistimed.