We describe a new species of colubrid snake of the genus Coniophanes from the Pacific coast of Michoacán, Mexico. This species is known from a single adult female collected near sea level in dry deciduous forests. The new species is most similar to C. piceivittis, C. schmidti and C. taylori. It shares with these three species 25 scale rows at midbody, a small sub-preocular scale, and a pattern of three dark brown stripes over a pale brown body. The new species differs most noticeably from the other three in possessing a narrower dark vertebral stripe. Coniophanes p. taylori is elevated to a species status, therefore the C. piceivittis group consists of four species.