Schoenus gracillimus
Schoenus gracillimus is a species of sedge endemic to the Western Cape Province of South Africa. Description. The inflorescence of "S. gracillimus" has few spikelets (usually less than five), which is similar to "Schoenus adnatus", "Schoenus crinitus" and "Schoenus schonlandii". However, the spikelets of "S. gracillimus" are often pendulous (hanging) on long pedicels, whereas the other three species do not share this character. Compared to both "S. adnatus" and "S. gracillimus", "S. crinitus" is a more hairy and rigid species. In addition, "S. gracillimus" does not have spikelet receptacles that are adnate to the basal glume (bract), as  in "S. adnatus". Although there are slight differences in plant and spikelet form, the distributions of "S. gracillimus" and "S. schonlandii" differ ("S. gracillimus" generally grows more to the west). Difficulties in identifying the southern African "Schoenus" might be partially explained by their tendency to form hybrids with each other. Preliminary evidence suggests that "S. gracillimus" might form hybrids with other southern African "Schoenus" species. Taxonomy. "Schoenus gracillimus" is a species in family Cyperaceae, tribe Schoeneae. This tribe includes other notable genera such as "Costularia", "Gahnia", "Lepidosperma", "Oreobolus" and "Tetraria". Phylogenetic and morphological evidence suggests that species in the "Epischoenus  group are the closest relatives to S. gracillimus". The genus "Tetraria" once included species from the southern African "Schoenus"; however, we now know that the two groups are evolutionary distinct based on morphological and molecular differences. Several species of "Epischoenus" and the southern African "Tetraria" were transferred into "Schoenus" to ensure that the genus is monophyletic (i.e. the genus only has closely related species). In the field, the main distinguishing characters between "Tetraria" and "Schoenus" are the lack of stem leaves and absence of reticulate sheaths at the bases of the flowering stems in the latter genus. Distribution and habitat . Most collections of "Schoenus gracillimus" have been from damp sites in the mountains of Western Cape Province. However, some collections have been made from elevations near sea level.