The genus Cnidoscolus (Euphorbiaceae) contains some species with socioeconomic and cultural relevance in the Yucatan Peninsula, Mexico. There is little published information on the traditional knowledge of this genus, and the recent movements of younger people to more populated cities and towns risks this knowledge being forgotten. To preserve this knowledge, we wanted to answer the questions: what are the species or varieties of the plant with the generic name chaya that the contemporary Maya population uses in the Yucatan Peninsula, and in which agroecosystems are these species or varieties found? Nine local communities were selected for interviews in which the general population and healers shared their knowledge about the uses and management of Cnidoscolus spp. Through these interviews, we identified eight species or cultivars used by these communities: six cultivars of C. aconitifolius (chay, makat chay, chaysin espinas, ch'inch'in chay, tsaj, and tsaj/hoja de papaya), C. multilobus (tsaj), and C. souzae (tsaj). Within homegardens chay, makat chay and chaysin espinas are utilized for their feeding, medicinal and fodder value; while ch'inch'in chay and tsaj are utilized for their feeding, medicinal, and living-fence potential. In paddocks, ch'inch'in chay and tsaj are utilized as livestock feed. Tsaj is used for handcrafts, and tsaj/hoja de papaya possesses spiritual-religious attributes. The feeding, medicinal, fodder, living-fence, spiritual-religious, and handcraft potential of species and cultivars of Cnidoscolus reflect their biocultural importance for Maya inhabiting the peninsula of Yucatan.
