is a Mexican mycologist
. He is considered the world's foremost authority on the genus Psilocybe
. and published comprehensive book on the subject in 1977, he has since authored eight other books and over 350 papers on Mexican mushrooms. He currently holds the Emeritus Research chair at the Ecological Institute of Xalapa
where he founded Department and Herbarium of Fungi. He is also a guide on "Mexican Mushroom Tours."