Morphological phylogeny of Tradescantia L. (Commelinaceae) sheds light on a new infrageneric classification for the genus and novelties on the systematics of subtribe Tradescantiinae Author Pellegrini, Marco O. O. https://orcid.org/0000-0002-8783-1362 Universidade de Sao Paulo, Departamento de Botanica, Rua do Matao 277, CEP 05508 - 900, Sao Paulo, SP, Brazil & Jardim Botanico do Rio de Janeiro, Rua Pacheco Leao 915, CEP 22460 - 030, Rio de Janeiro, RJ, Brazil & Current address: Smithsonian Institution, NMNH, Department of Botany, MRC 166, P. O. Box 37012, Washington D. C. 20013 - 7012, USA marcooctavio.pellegrini@gmail.com text PhytoKeys 2017 2017-10-26 89 11 72 http://dx.doi.org/10.3897/phytokeys.89.20388 journal article http://dx.doi.org/10.3897/phytokeys.89.20388 1314-2003-89-11 9C1BFFADD6208818FFDAFFD9FC60390A 1138297 1. Elasis D.R.Hunt, Kew Bull. 33(2): 332. 1978. Fig. 6K-L Tradescantia sect. Coholomia D.R.Hunt, Kew Bull. 35(2): 440. 1980., Syn. nov. Type species. T. guatemalensis C.B.Clarke ex Donn.Sm. [≡ E. guatemalensis (C.B.Clarke ex Donn.Sm.) M.Pell.]. Type species. Elasis hirsuta (Kunth) D.R.Hunt (≡ Tradescantia hirsuta Kunth). Comments. A taxonomic revision of Elasis is currently being prepared (Pellegrini and Hunt, in prep.) and should address pending taxonomic problems in the genus. In gross flower morphology, Elasis can be confused with Tradescantia and most of its segregate genera (i.e. some species of Callisia , Gibasis , Matudanthus , Thyrsanthemum , Gibasoides , and Sauvallea ). Nonetheless, Elasis can be easily differentiated from these genera due to its sessile inflorescence, with 1-several fasciculate, non-geniculate cincinni, pedicellate flowers, petals lacking tannin cells, inconspicuous connectives, and truncate stigma (Fig. 5 , clade C; Fig. 6K-L ).