Memecylon macneillianum M. Das Das, G. S. Giri, A. Pramanik and D. Maity, a new species from the southern Andaman Islands in India, is described and illustrated. It differs from its closely related species M. oleifolium Blume by having both terminal and axillary inflorescences, a higher number (mostly 3-7) inflorescences per node, longer and acutely quadrangular, distinctly furrowed primary inflorescence axes, distinct calyx lobes, and globose fruits. Moreover, in M. macneillianum the leaves are thicker, coriaceous and yellowish on both surfaces when dry, whereas in M. oleifolium the leaves are thin, chartaceous and olive green with a distinctive rusty-red blush around the midvein on drying. © 2016 Royal Botanic Gardens and Domain Trust.