Cyperus ovatus Baldwin. Phen: Jul-Oct. Hab: Sandy beaches, maritime forests, and pinelands. Dist: Se. NC south to s. FL, west to s. AL.
ID notes: Because of similarities in habit and inflorescence form, Cyperus ovatus var. ovatus has been confused with C. retrorsus, from which it can be readily distinguished by its 3-5 fruited spikelets; apically conduplicate, ascending, whitish yellow to golden brown or stramineous floral scales; narrowly elliptic to fusiform achenes; yellow-green to light green foliage; and typically spreading to divaricate (rarely ascending) primary inflorescence bracts. Cyperus ovatus var. ovatus varies along a south-north cline. An extreme form with longer spikelets, broader nearly globose spikes, and generally fewer inflorescence rays is restricted to southern peninsular Florida and has been called C. winkleri. The incidence of this form decreases northward as the more common and more widespread form becomes predominant. Hybrids between C. retrorsus and C. ovatus do occasionally occur, and it seems likely that some of the variation observed in C. ovatus is the result of introgression between southern Florida populations of C. ovatus, where the winkleri-form is more common, northward into populations of C. retrorsus. Hybrids between C. ovatus var. ovatus and C. croceus, C. retrorsus, and C. strigosus have been observed.
Origin/Endemic status: Endemic
Synonymy: = FNA23, K1, K4, WH3; >< Cyperus cylindricus Elliott; > Cyperus deeringianus Britton ex Small – S; < Cyperus retrorsus Chapm. – C, G, GW1, W; ? Cyperus retrorsus Chapm. var. cylindricus (Elliott) Fernald & Griscom; > Cyperus retrorsus Chapm. var. deeringianus (Britton ex Small) Fernald ex Griscom – RAB; > Cyperus winkleri