Taxonomic notes for Portulaca (Portulacaceae) in South America II: synonymisation of P. diegoi under P. hatschbachii based on macro and microcharacters

Portulaca diegoi is here proposed as a heterotypic synonym (synon. nov.) of P. hatschbachii, a species endemic to southern Brazil. Analysis of type specimens and protologues of both names demonstrated that they do not differ in root, leaf, flower, fruit or seed morphology. P. hatschbachii can be distinguished from other Portulaca species by its decumbent habit, oblanceolate leaves with purplish and recurved apex, lanate leaf axillary trichomes, hemispheric operculum and thick and elongated roots. In addition, based on examination of specimens of P. hatschbachii, they are quite distinct, because their leaves turn black after drying. Illustrations and comments about the taxonomy, phenology, distribution, habitat and conservation status are provided for P. hatschbachii.