vThis stamp booklet celebrates the beauty of cacti, flowering perennial succulents that are abundant in the Southwest and other parts of the world. Most cacti grow very slowly and are tough, adaptable and low maintenance.
Cactus flowers are often large and flamboyant, with colors of white, red, pink, orange or yellow. Some flowers are also richly scented, and the nectar and colors attract pollinators such as bats, bees and birds.
These stamps celebrate the beauty of the cactus flower; each stamp features a photograph of one of these ten cacti flowers:
The distinctive characteristics of the populations of Parodia scopa (Sprengel) N. P. Taylor living in the Quebradas of Treinta y Tres Department, in Uruguay, known as Notocactus scopa var. marchesi W. R. Abraham or Parodia scopa ssp. marchesi (W. R. Abraham) Hofacker, consist of a smaller number of ribs (23-28), always within the range of the species (25-40), and whitish central spines, sometimes yellowish, as confirmed by our investigations. Even this feature does not appear to be exclusive of populations to Trenta y Tres, since other groups of P. scopa living in Rio Grande do Sul (Brazil) are described with white central spines, such as Notocactus scopa var. ramosus (Osten) Backeberg, (white to dark brown), yellow as Notocactus scopa var. daenikerianus Krainz (from yellow to honey-colored), or like Notocactus scopa var. glauserianus Krainz, from orange to brownish yellow. For these reasons, besides the fact that no other factor distinguishes it from the other populations of P. scopa, if not a relative geographical isolation (even included in the territorial area of the species), we consider the marchesi form not so defined to assume the rank of species; and we believe that the taxa that have been considered till now at infraspecific level are synonyms of P. scopa.
