Historia natural de Dioon Merolae (Zamiaceae)en Chiapas, México

We compiled observations from six populations of Dioon merolae (Zamiaceae) located in the Central Depression (530-600 m) and the Sierra Madre of Chiapas (1,100-1,200 m). More than 800 individuals of different size and in all phenological stages were visited during 1997 and 2010. A revision of the phylogenetical relationships and distribution of D. merolae is included, along with a botanical description complemented with original observations. The growth of stems is described from seedlings up to adult plants, as well as the production of basal suckers, root growth, and the production of leaves, strobili and seeds. Plant-animal interactions involved in pollination, herbivory, and seed dispersal and predation are described. The effects of occasional wild fires on survival and reproduction are discussed, as well as the longevity and age estimation of this long-lived species. D. merolae populations are severely threatened due to a local religious ceremony in which adult plants are heavily or almost completely (sometimes partially) defoliated. The conservation implications of this practice are discussed.