Typification of names in Cyperus section Arenarii (Cyperaceae)

The typification of names in the genus Cyperus was done as part of an ongoing study of the section Arenarii. The latest monograph on the genus by Kukenthal (1936), accepted eight species in the section Bobartia (=Arenarii), and a number of lower level taxa, which are treated here either as distinct species or synonyms. The taxonomic treatment of the core species, C. conglomeratus Rottb., turned out to be especially confusing, which is reflected in the past identifications of the material, and consequently, has created wrong interpretations on the distributions. C. jeminicus Rottb. has similarly caused a lot of confusion. Currently we recognize 26 species in the section, with two subspecies in C. conglomeratus. Most names in the section have not earlier been typified. Here we designate lectotypes for 33 names, three epitypes, and one neotype. Cyperus sections Arenarii Kunth and Hymenolepides Nees are typified also.