Tradescantia sect. Austrotradescantia D.R.Hunt, Kew Bull. 35(2): 440. 1980.

Pellegrini, Marco O. O., Forzza, Rafaela C. & Sakuragui, Cassia M., 2017, Novelties in Brazilian Tradescantia L. (Commelinaceae), PhytoKeys 80, pp. 1-31 : 3

Tradescantia sect. Austrotradescantia D.R.Hunt, Kew Bull. 35(2): 440. 1980.

Diagnosis.

The section is characterized by perennial herbs, with thin and fibrous roots, definite or indefinite base, rhizomes absent, leaves with asymmetric base, inflorescences terminal or at the apex of the stems, pedunculate, cincinni bracts leaf-like or rarely spathaceous, bracteoles inconspicuous, flowers flat, sepals equal, free, generally keeled, petals free, sessile, stamens 6 and equal, free, filaments straight at post-anthesis, basally densely bearded with long moniliform hairs, connectives rhomboid, anther sacs elliptic, ovary glabrous, stigma punctate, seeds costate, rarely rugose, embryotega inconspicuous and dorsal ( Pellegrini 2015; Pellegrini et al. 2016).

Comments.

Tradescantia sect. Austrotradescantia has been the subject of several recent studies ( Pellegrini 2015, 2016, 2017; Pellegrini et al. 2015, 2016; Funez et al. 2016). Species diversity in this section is centered in Southeastern and Southern Brazil, where all of the accepted species occur. However, some species in the group have a wider distribution, reaching neighboring countries like Argentina, Bolivia, Paraguay, and Uruguay ( Pellegrini 2015; Pellegrini et al. 2016). Tradescantia sect. Austrotradescantia has recently been revised, and its morphology thoroughly analyzed in a yet unpublished MSc thesis ( Pellegrini 2015). As part of our revision of this section, we describe a new species, report the rediscovery and inclusion of T. valida in the section, and a new synonym for T. crassula (with a correction of its typification).