The circumscription of the two Arabian speciesSarcostemma forskaolianumSchult. andS. vanlesseniiLavranos is clarified.S. vanlesseniiis identified as a widespread species, occurring in East Africa and the southern Arabian Peninsula. Within theSarcostemma viminalecomplex, three new subspecies are delimitated. Subspeciesodonlolepis(Balf.f.) Meve&Liede, comb, et stat. nov. is established for glabrous, strongly twinning plants close to those of subspeciesbrunonianum(Wight&Am.) P.I. Forst., but distinguished by flower‐bearing laterals and an outer corona half as high as the gynostegium. Ecologically, this taxon is confined to coastal habitats in East Africa. Subspeciesstipilaceum(Forssk.) Meve&Liede, comb, ct stat. nov. covers stout, non‐twining representatives of East Africa and Arabia, also with short flower‐bearing laterals. SubspeciessuberosumMeve&Liede, subsp. nov. is newly described to accommodate the most frequent East African form ofS. viminale, often mistaken for the typical subspecies. All taxa are described in detail, chromosome numbers are given and distribution maps are provided forS. forskaolianum, S. vanlesseniiandS. viminalesubsp.odontolepis.A synopsis of all taxa occurring in East Africa and Arabia and additional chromosome numbers are pro