Monographs Details: Scleria
Authority: Maguire, Bassett. 1965. The Botany of the Guayana Highland. Mem. New York Bot. Gard. 12 (3): 1-285.
Discussion:Hypoporum Nees, Linnaea 9: 303. 1834.
Hymenolytrum Schrader ex Nees, Fl. Bras. 2(1): 147. t. 22. 1842.
CTiondrolomia Nees, Fl. Bras. 2(1) : 173. 1842.
Macrolomia Schrader ex Nees, Fl. Bras. 2(1) : 181. t. 24. 1842.
Omoscleria Nees, Fl. Bras. 2(1) : 180. 1842.
Mastigoscleria Nees, Fl. Bras. 2(1): 177. 1842.
Ophryoscleria Nees, Fl. Bras. 2(1) : 182. t. 25. 1842.
Schizolepis Schrader ex Nees, Fl. Bras. 2(1): 169. t. 25. 1842.
Trachylomia Schrader ex Nees, Fl. Bras. 2(1): 174. 1842.
The name "Scleria," derived from Greek, hardness, in allusion to the indurated fruits, was first used for these plants in 1765 by Peter Jonas Bergius. Previous to that time, however, certain species of the genus had been described as members of other genera. The earliest mention of any plant which may with certainty be placed in this genus was in 1707, when Hans Sloane described and figured a Jamaican plant which he called Gramen cyperoides sylvaticum maximum geniculatum aspcrius, seminc milii folis. This is clearly the plant now known as Scleria secans.
Scleria lithosperma, the most widely distributed species of the genus, was first described by Linnaeus in 1753 as Scirpus lithospermus. In 1762 he transferred the plant to the genus Schoenus, but it was not placed in Scleria until 1788 by Swartz. The second plant to be described and named was the one now known as Scleria secans, originally placed by Linnaeus in Schoenus.
The genus retained its integrity until 1834, when Nees separated the species with a minute or obsolete hypogynium under the name Hypoporum. Eight years later Nees carried this dismemberment to a point where the genus Scleria proper was reduced to only a few species and the majority of the American species were rather artificially segregated under the new genera Hymenolytrum, Chondrolomia,
Macrolomia, Omoscleria, Mastigoscleria, Ophryoscleria, Schizolepis, and Trachylomia.
Hymenolytrum was characterized by Nees in his key to the genera as follows:
"Spiculae femineae in eodem ramulo inferae, sessiles, uniflorae, masculae peduneulatae. Cupula pateriformis, stipitata. Perigynium membranaceo-trilobum lobis parvis distantibus." The name is retained in the present treatment as a section. The ten species known to belong to the group have tall stems and broad leaves with the very numerous spikelets densely clustered in pyramidal panicles. The genus Chondrolomia was founded on Scleria sellowiana, a species of southern Brazil bearing six tubercles on the hypogynium. It is clearly a member of the Tuberculatae series of the Euscleriae.
Macrolomia, as a genus, was erected for Scleria bractcata, a tropical American species with the pistillate spikelets distinctly segregated in the lower portion of the panicle and the staminate spikelets in the upper portion. This arrangement is unknown among the other American species, but from the fruit characters and the general appearance of the plant it belongs in the section Scleria. Omoscleria was founded on Scleria flagellum Sw., and Mastigoscleria on S. reflexa HBK . Both of these genera were based on artificial characters which do not differ widely from the general characters of the genus.
Ophryoscleria was characterized by Nees in his key as: "Cupula cum perigynio connata, profunde excavata, truncata, crassa, a perigynio ciliata." The eleven members of this section, as recognized in this treatment, are quite distinct in their habit and in general are identified by the ciliate margin of the hypogynium. The fact that this is essentially glabrous in S. schiedeana does not militate against its inclusion here, since the vegetative appearance of that plant clearly places it with the Ophryoscleriae.
Schizolepis was briefly characterized by Nees as follows: "Disci margo fimbriatus aut alte serratus." This section comprises eleven species, having the margin of the hypogynium deeply serrate or fimbriate. Trachylomia was founded on S. triglomerata and is not separated from Scleria proper by characters of generic rank. In the present treatment some of these are retained as names of sections of Scleria. The American species are grouped into the five sections, Hypoporum, Ophryoscleria, Hymenolytrum, Schizolepis, a n d Scleria, all of which are represented in the Guayana region.
Specimens studied in the preparation of this paper are from the herbarium of The New York Botanical Garden, the National Herbarium (Smithsonian Institution), the Gray Herbarium, Missouri Botanical Garden, Botanischer Garten (Berlin-Dahlem), Chicago Natural History Museum, the herbarium of West Virginia University, and the Instituto Botanico, Caracas. Gratitude is expressed to administrators of these herbaria for their assistance in making the material available.