This member of the Fabaceae family was given this name by Lorenzo Raimundo Parodi in 1935. It is found in Argentina, Bolivia and Peru, growing in a well drained soil with some water and lots of sun. The caudex can grow to twelve centimetres in diameter, fifteen centimetres long, the entire plant from fifteen to 40 centimetres in height, but might have additional vines, reaching for 200 centimetres. The flowers are white to pale lavender. It have been grown as a root-crop for 1000s of years.
The genera name from Greek pachys; 'thick' and Greek rhiza; 'root' for the thick tuberous roots. The species name is the old Inca name for their crop.

