Under the name Bucephalandra motleyana 'Riam Macam' a rather small epiphytic plant from Borneo, which reached Germany around 2011, used to be traded; it is now Bucephalandra sp. 'Riam Macan'.1 It probably refers to the Riam Macan waterfall in Sanggau regency, West Kalimantan.12 It does not belong to B. motleyana in the narrow sense (Wong & Boyce 2014).1 That species is known only from Motley's collection and is not in cultivation.3
The dull, dark green to greyish green upper surface of the fairly tough, short-stalked leaves is very densely set with silvery dots (stomata); the blades are elliptic to obovate, new growth slightly reddish.1 The leaves usually lie flat, and submersed the rhizome mostly creeps with an upturned tip.12 Compared with the very similar 'Braun-rot' it has paler, firmer leaves and a larger inflorescence with a white rather than pale pink spathe, and it apparently grows more slowly.1
References and further reading: