Some notes about the genus Amaranthus in Iran

Some taxonomic and morphologic notes about the genus Amaranthus (Amaranthaceae) in Iran are here presented. More than 400 specimens were examined as well as extensive pieces of literature were analyzed. As a result, 17 taxa were recognized based on available literature. Information about their nomenclature (accepted names, main synonyms, and types), main morphological features and diagnostic keys at species and infraspecific levels were prepared. Pictures of inflorescences, fruits and tepals of all taxa in Iran were also provided in order to obtain undoubted and clear descriptions of Amaranthus taxa in the country and a functional identification key on the basis of the features of the reproductive organs was constructed. The distribution of this genus in Iran has also been briefly discussed.