S. palarostris is cross-banded with black, yellow (or whitish), and red bands. Consequently, it resembles the Sonoran coral snake (
Micruroides euryxanthus). The
mnemonic "red on yellow kill a fellow, red on black, friend of Jack" doesn't work with this snake. However, unlike the
coral snake, which has a black snout,
Sonora palarostris has a yellow snout and is not
venomous. Also on a coral snake, the bands go all the way around, but
S. palarostris has a solid yellow belly. The smooth
dorsal scales are arranged in 15 rows at midbody;
ventrals, 141–181;
subcaudals, 34–64, divided. Maximum total length (including tail) of adults is . ==Subspecies==