Coelorachis
Rottboellia similar but with hispid nodes and sheaths
Hemarthria with similar but flattened (vs. cylindric) pencil-like raceme
1. Spikelets strongly rugose; rachis adjacent to the sessile spikelet bent; flowering spring-summer…C. rugosa
1. Spikelets smooth or nearly so; rachis adjacent to the sessile spikelet straight; flowering summer-autumn…C. tuberculosa