Taxonomy and leaf anatomy of the genus <i>Ehrharta</i> (Poaceae) in southern Africa: the Ramosa group

Abstract

The Ramosa species group in the genus Ehrharta is distinguished morphologically by small spikelets with sterile lemmas similar to each other, with tips rounded, truncate or mucronate, with sides glabrous, scabrous or shortly hairy, and with bases appendaged and usually bearded. The rectangular intercostal long cells with sinuous walls, the dome-shaped stomata with a raised rim surrounding the pore aperture, the absence of epicuticular wax and the microhairs without a tapering distal cell are diagnostic anatomically. The Ramosa group is composed of two species: E. ramosa (Thunb.) Swartz subsp. ramosa, subsp. aphylla (Schrad.) Gibbs Russell and E. rehmannii Stapf subsp. rehmannii; subsp. filiformis (Nees) Gibbs Russell; subsp. subspicata (Stapf) Gibbs Russell. All taxa are linked by intermediates to one or two others in the group. The closest relationship of the Ramosa group is to the Calyeina species group, on the basis of both morphological and anatomical characters.

Keywords

• Capensis
• culm anatomy
• <i>Ehrharta</i>
• Fynbos
• leaf anatomy
• Poaceae
• taxonomy