I've seen what appears to be two sea snakes washed up on the beach - in Teacapan a few years ago and again a few days ago in Mazatlan. From what I can tell online these are way out of their customary ...
Just re-read the discriptions from my book. The one snake mentioned is the "Yellow Bellied Sea Snake" and fit the discription of the one-foot long snake found by the Mexican boys a few years ago in Bahia Tenacatita