Agdestis

Agdestis is a genus of flowering plants containing a single species Agdestis clematidea, a vine native to Florida, Texas, Mexico, and Central America. Its common name rockroot refers to the large boulder-like root.
Taxonomy.
"Agdestis" is usually placed in the Phytolaccaceae family. Its classification is uncertain, however, as several studies of molecular phylogenetics have found it to be possibly the sister taxon of "Sarcobatus", also of uncertain classification and often placed in its own family, Sarcobataceae.