A synopsis of Euphorbia subgen. Chamaesyce (Euphorbiaceae) in Iran

This paper is the first taxonomic revision of Euphorbia subgenus Chamaesyce in Iran since the publication of Flora Iranica in 1964. We provide a key, descriptions, and illustrations for the eight species of the subgenus occurring in Iran. Euphorbia nutans is reported as a new record for the flora of Iran, E. humifusa is recognized to have two forms, pilose and glabrous; the pilose form is a first report for Flora Iranica, and E. granulata var. turcomanica is reported as a synonym of E. granulata. The following information is given for each species: accepted name, synonymy, habitat, ecology, and geographical distribution.