A taxonomic synopsis and morphological characterization of Myoxanthus (Orchidaceae: Pleurothallidinae) Author Rojas-Alvarado, Gustavo 0000-0002-8918-0823 Jardín Botánico Lankester, Universidad de Costa Rica, Cartago, Apartado 302 - 7050, Costa Rica & gustavo. rojasalvarado @ uc. ac. cr; https: // orcid. org / 0000 - 0002 - 8918 - 0823 gustavo.rojasalvarado@uc.ac.cr Author Blanco, Mario A. 0000-0001-7369-5411 Jardín Botánico Lankester, Universidad de Costa Rica, Cartago, Apartado 302 - 7050, Costa Rica & Centro de Investigación en Biodiversidad y Ecología Tropical, Universidad de Costa Rica, Apdo. 11501 - 2060 San José, Costa Rica & Escuela de Biología, Universidad de Costa Rica, Apdo. 11501 - 2060 San José, Costa Rica & mario. blancocoto @ ucr. ac. cr; https: // orcid. org / 0000 - 0001 - 7369 - 5411 mario.blancocoto@ucr.ac.cr Author Karremans, Adam P. 0000-0001-5987-7710 Jardín Botánico Lankester, Universidad de Costa Rica, Cartago, Apartado 302 - 7050, Costa Rica & Naturalis Biodiversity Center, Endless Forms, Sylviusweg 72, Leiden 2333 BE, The Netherlands & akarremans @ gmail. com; https: // orcid. org / 0000 - 0001 - 5987 - 7710 akarremans@gmail.com text Phytotaxa 2021 2021-06-10 507 3 211 258 http://dx.doi.org/10.11646/phytotaxa.507.3.1 journal article 10.11646/phytotaxa.507.3.1 1179-3163 5425729 52. Myoxanthus xiphion Luer (1982a: 51) . (Fig. 18L) TYPE :— Ecuador . Napo : epiphytic in wet forest south of Baeza , 1500 m , 11 Aug 1978 , Luer , Luer , Andreetta & Hirtz 3267 ( holotype ,: SEL !). Distribution: — Ecuador , Colombia , Bolivia and Peru . Notes:— This species is similar to M. parvilabius in having lateral sepals connate at the base forming a flat synsepal and falcate petals. However, M. xiphion is distinguished by the caespitose habit vs . proliferous, yellowish flowers vs . purplish and subquadrate base of the petals, trilobed just above the middle and abruptly contracted into a falcate middle lobe vs . obovate base contracted into a slender falcate apex.