Do Waldsteinia and Obregonia contain the same number of species?
Obregonia Obregonia, the artichoke cactus, is a genus of cacti with a single species, Obregonia denegrii. The species is endemic to the state of Tamaulipas in Mexico.
Olmediella Olmediella is a monotypic genus of flowering plants in the willow family, Salicaceae. It consists of one species of trees: Olmediella betschleriana, which is native to Central America. Formerly placed in the heterogeneous family Flacourtiaceae, "Olmediella" is now classified in Salicaceae, along with close relatives "Bennettiodendron", "Carrierea", "Idesia", "Itoa", "Macrohasseltia", "Poliothyrsis", and even the willows ("Salix") and cottonwoods ("Populus") themselves.