Eight new species of Coccoloba sect. Campderia (Polygonaceae, Eriogonoideae) from Mexico and Central America

Background and Aims: Coccoloba sect. Campderia comprises 14 species, which are recognized by the presence of fruits in the form of diclesia. During the review of herbarium specimens for the taxonomic treatment of the genus Coccoloba for the Flora de Veracruz and the Flora Mesoamericana, several specimens with fruits in the form of diclesia, which do not correspond to any of the species of the sect. Campderia so far described, were located. Therefore, in this work eight new species of Coccoloba sect. Campderia are described and illustrated. Methods: Physical and digital specimens from various herbaria were observed, including type specimens. The existing taxonomic literature on the genus Coccoloba was also consulted. The morphological description, illustrations, distribution map, as well as the assessment of the conservation status of each of the new species are presented. A dichotomous key to all species of the sect. Campderia from Mexico and Central America is included. Key results: Coccoloba burgeri, C. carnevalii, C. costaricensis, C. glandulosa, C. rodriguezii, C. ulloae, C. veracrucensis and C. victoriasosae are described and illustrated as new species. Coccoloba burgeri, C. costaricensis, C. glandulosa are endemic to Costa Rica while the rest are endemic to Mexico. Conclusions: The review of herbarium specimens and literature, combined with the description of the new species of Coccoloba sect. Campderia increase its species number to 28, which can be delimited by a set of character states of the leaves, inflorescences and fruits. Flowers are not helpful to delimit the species in the sect. Campderia.