Schismus

Plants annuals or short-lived perennials; tufted. Culms 2-30 cm, sometimes decumbent, glabrous. Sheaths open, usually shorter than the internodes, with tufts of 1.5-4 mm hairs on the margins of the collars; auricles absent; ligules membranous, ciliate; blades flat or folded, becoming involute on drying. Inflorescences terminal, dense panicles, 1-7 cm long, 0.5-2(3) cm wide, branches 1-2 per node; disarticulation initially above the glumes, glumes and pedicels sometimes falling together later. Spikelets with (4)5-7(10) florets. Glumes subequal, exceeding or exceeded by the distal floret, 3-7-veined, margins hyaline; lemmas 7-9-veined, margins and intercostal regions usually pubescent, varying to glabrous, margins hyaline, apices bifid or merely notched, sinuses sometimes mucronate, mucros to 1.5 mm; paleas spatulate, membranous, 2-veined, 2-keeled; anthers 3, 0.2-0.5 mm. Caryopses ovoid, x = 6.

Distribution

N.Mex., Tex., Utah, Calif., Ariz., Nev.

Discussion

Schismus is a genus of five species that is native to Africa and Asia. Two species are established in the Flora region. In using the key and descriptions, the lowest floret in a spikelet should be examined. Succeeding florets tend to have shorter, less acute or acuminate lobes, and a shallower sinus.

Selected References

Conert, H.J. and A.M. Turpe. 1974. Revision der Gattung Schismus (Poaceae: Arundinoideae, Danthonieae). Abh. Senckenberg. Naturf. Ges. 532:1-81.

Lower Taxa

Schismus arabicus, Schismus barbatus

Key

1	Lower glumes equaling or exceeding the distal florets; lemma lobes longer than wide, acute to acuminate; paleas always shorter than the lemmas	Schismus arabicus
1	Lower glumes exceeded by the distal florets; lemma lobes as wide as or wider than long, acute to obtuse; paleas of the lower florets in the spikelets as long as or longer than the lemmas	Schismus barbatus