These two types of plants of Ixora have been bothering me for a long time. Both differ clearly from similar species I. pavetta in much longer corolla tube, 20-30 mm long. Both have nearly elliptic-lanceolate to elliptic-oblanceolate leaves, 6-20 cm long, with cuneate base and narrowed to 5-10 mm long petiole. Both have white flowers, which in one (sp-a) are lesser in number, forming a spreading inflorescence and petals are flat nearly 2.5 mm wide. In second (sp-b) flowers are more in number, dense and forming nearly globose inflorescence; with corolla lobes which are mostly reflexed along the margin (and looking similar to I. pavetta) so that they look very narrow (hardly 1-1.5 mm wide), but a few flowers would have flat corolla lobes which may be up to 2.5 mm wide or so (latter has been tentatively identified by Dinesh ji as I. finlaysoniana).
Ixora polyantha is described from Malabar in India and is commonly cultivated in Pakistan and India according to eFlora of India. Ixora finlaysoniana is plant from Thialand, Phillippines, widely cultivated in China and N E India, as per eFlora of China.
I have tried to find out differences between the two species from available sources, but could not succeed. Could any member lay hands to a publication which describes and keys out both the species, so that our specimens can be clearly fixed?.
Dr. Gurcharan Singh
Retired Associate Professor
SGTB Khalsa College, University of Delhi, Delhi-110007
Res: 932 Anand Kunj, Vikas Puri, New Delhi-110018.
Phone: 011-25518297 Mob: 9810359089http://people.du.ac.in/~singhg45/