Fruit structure and generic delimitation of Athanasia (Asteraceae‐Anthemideae) and related South African genera

Within South African Asteraceae‐Anthemideae there is a group of genera containing furanosesquiterpenes rather than the common polyacetylenes. Of these genera, Asaemia (Harv.) Ham. ex Benth. & Hook., Athanasia L., Eumorphia DC., Gymno‐pcnfzia Benth., Phymaspermum Less. and Sfilpnophyfon Less. have been investigated morphologically especially with respect to fruit structure. As a result of the investigations Stilpnophyton has been reduced to synonomy under Athanasia L. emend. Källersjö (with 36 spp.) and five species of Athanasia, together with Phaeocephalus S. Moore., are placed in the revived genus Hymenolepis Cass. (with 7 spp.). Brachymerk DC. and four misplaced species of Aihanasia are included in Phymaspermum Less. emend. Källersjö (with 17 spp.). Nine other misplaced species of Athanasia and one Pentzia Thunb. species have been described as a new genus Inulanihera Källersjö (with 10 spp.), a group without furanosesquiterpenes. The two monotypic genera Asaemia and Gymnopentzia, and Eumorphia (with 6 spp.) remain unchanged. The interrelationships of the genera possessing furanosesquiterpenes are shown in a cladogram. There are 25 new combinations in Afhanasia, Znulanthera, Hymenolepis and Phymaspermum.