Revista Mexicana de Biodiversidad Revista Mexicana de Biodiversidad 91 (2020): e913339 Taxonomy and systematics Tree and tree-like species of Mexico: Euphorbiaceae, Peraceae, Phyllanthaceae, Picrodendraceae, Putranjivaceae, and Urticaceae Especies arbóreas y arborescentes de México: Euphorbiaceae, Peraceae, Phyllanthaceae, Picrodendraceae, Putranjivaceae y Urticaceae Victor W. Steinmann a, Martin Ricker b, * a Facultad de Ciencias Naturales, Universidad Autónoma de Querétaro, Avenida de las Ciencias s/n, Delegación Sta. Rosa Jáuregui, 76230 Ciudad de Querétaro, Querétaro, Mexico b Departamento de Botánica, Instituto de Biología, Universidad Nacional Autónoma de México, Apartado postal 70-367, 04510 Ciudad de México, Mexico *Corresponding author:
[email protected] (M. Ricker) Received: 30 December 2019; accepted: 21 May 2020 Abstract Trees or tree-like plants are defined here broadly as perennial, self-supporting plants at least 5 m tall, without considering ascending leaves or inflorescences, and with 1 or several erect stems with a diameter of at least 10 cm. In this fourth contribution of the taxonomic compilation of Mexico’s native tree species, 178 species are presented: 134 in the family Euphorbiaceae (53% endemic), 1 in the Peraceae (not endemic), 12 in the Phyllanthaceae (none endemic), 1 in the Picrodendraceae (endemic), 3 in the Putranjivaceae (1 endemic), and 27 in the Urticaceae (7% endemic). The tallest tree species are Tetrorchidium rotundatum (Euphorbiaceae) reaching 45 m, and Hieronyma alchorneoides (Phyllanthaceae) being over 40 m, as reported on herbarium labels or in the literature. All species are listed in an appendix that includes the original publication, references of taxonomic revisions or floristic treatments, in some cases synonyms, existence of subspecies or varieties, maximum height in Mexico, and an indication if the species is endemic to Mexico.