Three new genera of Gesneriaceae from limestone of Peninsular Malaysia

Three superficially similar species from Malayan limestone, Boea minutiflora Ridl., Paraboea bettiana M. R. Hend. and an unnamed plant from Taman Negara have been investigated from newly available material. Differential characters of flowers and fruits override the vegetative similarities, which are probably due to ecological convergence in their shady, limestone habitats. It is concluded that these plants represent three distinct genera. These are described as Emarhendia (for Paraboea bettiana), and Senyumia (for Boea minutiflora), while the unnamed plant becomes Spelaeanthus chinii. Possible relationships are discussed and the formal taxonomy, together with a key to genera and necessary descriptions and transfers, is set out.