We often describe pachypus as being more of a shrub, as opposed to decaryi being a tree. Pachypus tends to get a much thicker trunk at an earlier age, as well as develop more branching. The generally accepted differentiation is pachypus's zig-zag branching, as well as yellow flowers instead of decaryi's red. It also tends to grow at about half the speed of decaryi, hence the disparity in price. Overall, pachypus is a must have for the Operculicarya and pachycaul tree collector. Growing in a 5" pot, you will receive the exact plant pictured.