Plants annual or perennial; monoecious or dioecious; often stoloniferous. Culms 5-40 cm, sometimes decumbent. Leaves mostly basal; sheaths open; ligules of hairs; blades 0.5-2 mm wide. Inflorescences terminal, racemelike panicles of short branches, usually exceeding the upper leaves, sometimes appearing 1-sided; branches about 0.5 cm, not appressed to the rachises, with 3 spikelets, bases strongly curved, shortly strigose, axes not extending beyond the distal spikelets; disarticulation at the base of the branches. Spikelets pedicellate or sessile, lateral spikelets with shorter pedicels than the central spikelet or sessile; lateral spikelets with 2 florets, lower florets usually staminate or sterile, rarely pistillate, upper florets much reduced, usually sterile; central spikelets pedicellate, with 3 florets, lowest florets bisexual or pistillate (staminate in staminate plants), distal florets staminate or sterile. Glumes 2, very unequal, shorter than the spikelets, unawned; lower glumes shorter than the upper glumes, those of the central spikelets flabellate, glabrous, veinless; upper glumes approximately equal to the adjacent lemmas, 1-veined, acuminate; lemmas thinner than the glumes, pilose, 3-veined, 4-lobed, all 3 veins excurrent, forming awns that equal or exceed the lobes, lobes of the sterile florets usually deeper than those of the other florets; paleas 2-veined, veins often extending as awns, x = 10.

Distribution

Ariz., Tex.

Discussion

Cathestecum is a genus of six species that extends from the southern United States to Guatemala; two are native to the Flora region. Columbus (1999) advocated including Cathestecum in Bouteloua, but the traditional treatment is adopted here.

Selected References

Beetle, A.A. 1987. Las Gramineas de Mexico, vol. 2. COTECOCA [Comision Tecnico Consultiva de Coeficientes de Agostadero], Mexico, D.F., Mexico. 344 pp.

Columbus, J.T. 1999. An expanded circumscription of Bouteloua (Gramineae: Chlorideae): New combinations and names. Aliso 18:61-65

Pierce, G.J. 1979. A biosystematic study of Cathestum and Griffithsochloa (Gramineae). Ph.D. dissertation, University of 'Wyoming, Laramie, Wyoming, U.S.A. 244 pp.

Lower Taxa

Cathestecum brevifolium, Cathestecum erectum

Key

1	Stolon internodes to 12 cm long, straight or almost so; culms 5-15 cm tall; spikelets frequently reddish or purplish; lateral spikelets of branches with bisexual florets poorly-developed, sterile (rarely staminate) florets; central spikelet on staminate branches with sparsely pilose lemmas	Cathestecum brevifolium
1	Stolon internodes usually 15 cm or longer, strongly arching; culms 10-30 cm tall; spikelets frequently pale green; lateral spikelets of branches with bisexual florets usually well-developed, usually staminate or sterile; central spikelet on staminate branches with glabrous lemmas	Cathestecum erectum