A Revision of the Genus Neuracanthus (Acanthaceae)

Abstract

Summary. The genus Neuracanthus is divided into 3 sections; 30 species are recognised, with a further 5 subspecies and 3 varieties. From tropical Asia (India to Vietnam) 4 species and one subspecies are recognised, all referred to sect. Neuracanthus which also has two species in north and northeast Africa. From Madagascar 6 species (3 newly described) are recognised, all of which are referred to sect. Didymosperma in which a further 6 species (1 described as new) from continental Africa are also included. The remaining 12 species (2 newly described) are referred to sect. Leucobarleria and are characteristic of the dry areas of northeastern tropical Africa and southern Arabian Peninsula. Many species appear to be very local and are poorly known. While the genus is clearly defined, its relationships to other genera and its position within the Acanthaceae are obscure.