Notes
Many times, the peculiarity of the western bend of the Andes in the Sierra near Santa Cruz with its climatic and biogeographical complexity, has been pointed out, Ibisch et al. 1996, and an important center of endemic Bromeliads ( B. Ibisch & Gross 1998, Ibisch et al. 1999a, b, Ibisch 2001, Ibisch & Vasquez 2003. Also other terrestrial plant groups like Cactaceae, Vellozia or Amaryllis where only a few have been described in recent times, are several endemic species,( B. Diers & Krahn 2003, Ibisch et al. 2001, Vasquez 2001).
A typical Bromeliad species in the red sandstone rocks and the steep hillsides in the hinterland of the Rio Pirai is Puya nana Wittmack, one of the unusual species of the genus, through the hemispherical sessile inflorescence, not rising above the leaf rosette,( fig. 1; vgl. Smith & Downs 1974). It had been discovered by Theodor Herzog as he traveled from Santa Cruz through the Achirastal near Samaipata. Wittmack described the species as the "Dwarf Puya ", which is inappropriate for such a large plant with a large rosette and a striking plant. Puya nana differs from the other species with normally branched inflorescence. Now, the authors found a candidate for the missing link: a plant, that is very much like the dwarf Puya, but with a long branched inflorescence. It could be the predecessor of Puya nana; however it just as possible, that insignificant genetic changes are enough to make the stunted growth of the inflorescence a retrograde step. In this case was the taxon now found derived from Puya nana. However - it should be given a very close relationship. Because the new plant was discovered not only as a single specimen, which could point out a spontaneous and unique mutation, but in a small population, and furthermore, since also some further differences are evident, we propose to describe it as new species here. —SeeDie Bromelie
