Plants perennial, tufted, sometimes with short, knotty rhizomes. Leaves 2-12 mm wide. Inflorescences panicles, narrow or open. Spikelets with 1 floret; glumes subequal, exceeding the floret; acuminate; lemmas coriaceous, with blunt calluses, partly or wholly hairy, with 2 minute apical lobes, awned from between the lobes; awns straight to curved.
The species treated here as Aristella were originally included in a very broadly interpreted Stipa. It is accepted here, with some hesitation. Multiple studies, molecular, morphological, and anatomical, have shown that Stipa should be interpreted more narrowly. Appropriate treatment of the excluded species is becoming clearer, but only Hamasha et al. (2011) have included Aristella keniensis [= Stipa keniensis] and Stipellula capensis [= Stipa capensis] together with numerous other Old World speices of Stipeae in the same molecular phylogenetic study. They recognized Aristella as a small genus of stipoid grasses distinguished by having brown lemmas and more or less straight awns, first recognized by Freitag (1985) as Stipa sect. Aristella. I have accepted Aristella here because it is clear Somaliland's only species of Stipeae does not belong in Stipa and Hamasha et al. (2011) supports its recognition, albeit somewhat weakly. These authors commented that its inclusion in a broadly interpreted Achnatherum was weakly supported by the molecular data but contradicted by the morphological data. Stipellula capensis, [= Stipa capensis] the other species of Stipeae native to Afica south and east of the Sahara, was not part of the same clade.