Harmsiopanax ingens

Harmsiopanax ingens of the Gensing, or Ivy Family (Araliaceae), is a very spiney palmlike mesocaul tree endemic to the montane rainforests of central New Guinea which bears a terminal rosette of deeply lobed, meter-wide (3.25-foot wide) dentate margined, peltate leaves (Sometimes not peltate), maple-like in shape, on equally long petioles. It ultimately attains a height of eighteen meters (59 feet), at which point it bears a huge panicle of flowers five meters (16.5 feet) high and equally wide; the largest above ground inflorescence of any dicot plant (although Caloncoba flagelliflora (Achariaceae; of West Africa) and Ficus geocarpa (Moraceae; of the Malay Peninsula) and Ficus unciata var. strigosa (also of Malaya) have larger subsurface panicles, each about nine meters (thirty feet) in length. H. ingens' panicles are very unusual; the ultimate twigs being spikes each bearing about fifty tiny umbels, each umbel with 8 to 20 minute flowers. So panicle, spike and umbel are all represented in a single inflorescence. Harmsiopanax ingens is monocarpic, and again the largest such plant among dicots. H. ingens was discovered in 1973 by  W. R. Philipson. Its native name is "makua".