Cephaelis hemicephaelis (Wernh.) Steyerm., Mem. N. Y. Bot. Gard. 17(1): 426. fig 41, a-e. 1967.
The individual flowers of an inflorescence lack subtending bracts, although the heads of flowers are surrounded by showy bracts, the species thus combining characters of Psychotria and Cephaelis, but not truly conforming to the concept of Cephaelis. In general aspect the species is intermediate between P. oblita Wernh. and P. ayangannensis Steyerm., resembling the latter in its obovate, rounded involucral bracts and the former in leaf shape. It differs from P. ayangannensis in the absence of cilia on the involucral bracts, much smaller corollas, and different leaf shape and apex. From P. oblita it differs in the obovate, rounded, nonciliate bracts of the involucre and much smaller corollas. From P. ayangannensis, moreover, it differs in the axis of the inflorescence remaining simple and unbranched above the junction of the peduncle and bracts, whereas in P. ayangannensis the peduncle becomes branched into several axes. From both P. ayangannensis and P. oblita it may be immediately recognized by the four main outermost bracts arising together at the base of the inflorescence to form a prominent involucre.