On Hydrangea peruviana, an endangered species from Ecuador, and Hydrangea oerstedii, very common in Costa Rica and Panama, and seven threatened Central and South American Hydrangeas, which have been confounded with these Author Samain, Marie-Stephanie https://orcid.org/0000-0002-7530-9024 Red de Diversidad Biologica del Occidente Mexicano, Instituto de Ecologia, A. C., 61600 Patzcuaro, Michoacan, Mexico mariestephanie.samain@gmail.com Author Granados Mendoza, Carolina https://orcid.org/0000-0003-4001-619X Departamento de Botanica, Instituto de Biologia, Universidad Nacional Autonoma de Mexico, 04510, Mexico City, Mexico Author Martinez Salas, Esteban Manuel Herbario Nacional de Mexico, Departamento de Botanica, Instituto de Biologia, Universidad Nacional Autonoma de Mexico, 04510, Mexico City, Mexico text PhytoKeys 2021 2021-01-26 171 91 153 http://dx.doi.org/10.3897/phytokeys.171.56351 journal article http://dx.doi.org/10.3897/phytokeys.171.56351 1314-2003-171-91 08DD30844BC558DB83D270DDFE99A853 7. Hydrangea schlimii Briq., Annuaire Conserv. Jard. Bot. Geneve 20: 400. 1919. Figures 2 , 12 Type. Colombia. Norte de Santander, Ocana , without date, ♂, old flowers, J.J. Linden 1139 (lectotype, designated by McClintock 1957 , pg. 238 [as "holotype" ]: G; isotypes: BR! [BR0000005119318], US! [00097002]). Description. The most complete description to date can be found in the treatment by Briquet (1919) , pages 400-401. Distribution. This species is currently known from the type locality in Colombia only (Fig. 2 ). Notes. This species concerns a very distinct taxon with more enlarged "marginal" flowers than any other member of Cornidia . In fact, from the type specimen it seems that most flowers possess enlarged sepals. It is only known from its type collection made around 1850 and to our knowledge has not been collected since. It cannot be excluded that it concerns a local "mophead" mutation, but in the absence of recently collected material and as the leaf morphology of the type specimens cannot be matched with better-known species, we decide here to recognize this taxon as a distinct species, although we cannot present an amended description at this time, given that we only dispose of the type specimen, which already was given an excellent description by Briquet (1919) . As in the case of H. durifolia , exploring field work in forests around Ocana in the Colombian department of Norte de Santander might lead to the rediscovery of this species, which will be helpful to define its taxonomic status. McClintock (1957) cited as "holotype" the collection in G, which we have not been able to locate. Based on the many enlarged marginal flowers and the inflorescence leaf morphology, this species should not be considered a synonym of H. oerstedii . The phylogenetic relationships of Hydrangea schlimii are yet unknown as there was no fresh material available for our molecular study (Granados Mendoza et al. unpublished results). Preliminary conservation status. We currently propose this species as Data Deficient (DD), as its taxonomic status in unclear, it is only known from the type locality, and no recent collections are available. Figure 12. Hydrangea schlimii . Branch with inflorescences with many enlarged flowers. Image of specimen Linden 1139 (BR).