Una Nueva Especie de Pachycereus (Cactaceae) del Occidente de

Pachycereus tepamo (Cactaceae, Cac- toideae, Pachycereeae), a new species from the low- er basin of the Balsas River, in the state of Mi- choacin, Mexico, is described and illustrated. Information concerning its habitat, geographic dis- tribution, and uses is also presented. In addition, morphological characters are used to compare this species with P grandis, P pecten-aboriginum, and P weberi, its closest allied species.