Organ Pipe Cactus, Stenocereus thurberi, with Fleshy Leaves on Spherical Short-Shoots that Have Indeterminate Growth

Abstract: Neoraimondia have short-shoots comprised of a large areole with indeterminate growth (‘Kurztriebcephalien’). Flowers of some other cacti are subtended by modestly large photosynthetic leaves. Many specimens of the organ pipe cactus, Stenocereus thurberi, seem to have all these traits: large short-shoots with indeterminate growth and fleshy photosynthetic leaves. Short-shoots in organ pipe cactus grow new photosynthetic leaves at their apical meristem and sometimes flower, branch, and form discrete areoles with new spines. However, unlike short-shoots in Neoraimondia, spherical short-shoots of Stenocereus thurberi seem to retain chlorenchyma and lack extensive cork development.