Smilax sect. Nemexia is a section of plants in the family Smilacaceae. It consists of the herbaceous plants within the genus Smilax. Smilax species fall into two groups with distinctive morphologies: one group has woody perennial stems with thorns and a vining habit, while the other group has herbaceous stems that die back to the ground each winter. S. sect. Nemexia is the taxon that comprises the herbaceous species. In the past it was often a genus of its own under the name Nemexia and taxonomists still need further study of the species of Smilax to determine its proper rank. However the widely accepted taxonomic system of the Flora of North America does not recognize Nemexia, nor does the AP-site. Thus Nemexia is not currently considered an accepted genus taxon by most plant taxonomists.