1. Oplismenus hirtellus (L.) P. Beauv., Ess. Agrostogr. 54, 168, 170 (1812).
Por R.W. Pohl y G. Davidse.
Panicum hirtellum L., Syst. Nat. ed. 10, 870 (1759). Lectotipo (designado por Hitchcock, 1908): Jamaica, Browne s.n. (LINN-80.28).
Perennes. Tallos erectos 60-90 cm; entrenudos glabros. Hojas glabras o pilosas; lígula 0.6-1.5 mm; láminas 4-12 cm x 4-20 mm. Inflorescencia 4-14 cm, densa; eje escabroso, puberulento o piloso; racimos 3-10, hasta 3.5 cm, compactos, las espiguillas traslapándose, hasta 4 mm de separación, el raquis más o menos uniformemente papiloso-híspido. Espiguillas 3-4 mm, glabras o pilosas, las aristas lisas; gluma inferior 1.7-2.5 mm, la arista 4-16 mm; gluma superior 1.8-2.7 mm, la arista 1.5-4 mm; flósculo inferior estéril; lema inferior 2.4-3.5 mm, 5-9-nervia; pálea inferior ausente; lema superior 2.3-3 mm; anteras 1.3-1.7 mm. Matorrales o bosques abiertos, arvense. T-P. 0-2300 m. (Pantropical.)
Existe una amplia intergradación entre ambas subespecies, y sería más realista reconocerlas en una categoría inferior.
Oplismenus hirtellus (L.) P. Beauv., Ess. Agrostogr. 54, 170. 1812; Panicum hirtellum L.
Perennes; tallos erectos 6090 cm de largo; entrenudos glabros. Hojas glabras o pilosas; lígula 0.61.5 mm de largo; láminas 412 cm de largo y 420 mm de ancho. Inflorescencia 414 cm de largo, densa, eje escabroso, puberulento o piloso, racimos 310, hasta 3.5 cm de largo, compactos, las espiguillas traslapándose, hasta 4 mm de separación, el raquis más o menos uniformemente papiloso-híspido; espiguillas 34 mm de largo, glabras o pilosas, las aristas lisas; gluma inferior 1.72.5 mm de largo, la arista 416 mm de largo, gluma superior 1.82.7 mm de largo, la arista 1.54 mm de largo; flósculo inferior estéril; lema inferior 2.43.5 mm de largo, 59-nervia; pálea inferior ausente; lema superior 2.33 mm de largo; anteras 1.31.7 mm de largo.
Pantropical. Existe una amplia intergradación entre ambas subespecies, y sería más realista reconocerlas en una categoría inferior.
Widely spreading perennial; culms with short internodes, freely branching, decumbent-spreading and rooting at the nodes, the erect or ascending branches 20-70 cm. long; sheaths glabrous to densely papillose-hispid, the margins ciliate, the lower ones usually much shorter than the internodes, the upper frequently overlapping; blades 4-10 cm., rarely 15 cm., long, 1-2 cm. wide, acuminate, usually asymmetric, rather thin, glabrous or sometimes pubescent, the margins scabrous; inflorescence 5-15 cm. long, of 3-7 stiffly ascending, rather distant racemes 1-2 cm., rarely 3 cm., long, the rachis more or less papillose-hispid, es- pecially at the base; spikelets 3-3.5 mm. long, glabrous to sparsely pilose; glumes about equal, 2 mm. long; awns glabrous, usually purplish, that of the first glume 5-10 cm. long, that of the second about 2 mm. long; sterile lemma acuminate; fruit 3 mm. long, elliptic, acute, minutely striate.
Plantas rastreras y erectas, 45–95 cm. Hojas con la vaina glabra; lígula hasta ca. 1.5 mm, inconspicua;lámina 3.5–13 cm × 4–18(–22) mm, glabra a papiloso-híspida. Infl. 4–15.5 cm, puberulenta a pilosa, los raci-mos hasta ca. 3.5 cm, compactos y moderadamente espaciados. Espiguillas 2.9–4.2 mm, traslapadas, separadaspor <3 mm, las aristas lisas; gluma inferior 1.7–2.5 mm, la superior 1.8–2.8 mm; flósculo superior 2.5–3 mm;lema inferior 2.5–3.5 mm, 5–9-nervada.
Straggling, often with long aerial roots from the nodes
Rather variable, particularly in the size, shape and hairiness of its leaf-blades, and also in panicle characters.
Inflorescence 3–15 cm. long, comprising 3–9 racemes each 0.5–3 cm. long with glabrous to sparsely pilose rhachis and ± contiguous spikelets, or the upper reduced to fascicles; sometimes all the racemes very short, but then the awns also short (less than 7 mm.).
Perennial with rambling culms 15–100 cm. long or more.
Leaf-blades narrowly lanceolate to narrowly ovate, 1–13 cm. long, 4–20 mm. wide.
Spikelets lanceolate, 2–4 mm. long, glabrous to sparsely pubescent; glumes with smooth viscid awns, the longest in each pair of spikelets 3–14 mm. long.
Rambling perennial with lanceolate to narrowly ovate leaf laminae.
Spikelets 2–4 mm. long, glabrous to sparsely pubescent; awns smooth and sticky, the longest in each pair of spikelets 3–14 mm.
Racemes with a distinct rhachis up to 3 cm. long, the spikelet pairs contiguous; rarely the racemes all ± cuneate, but then awns also short.
Prostrate perennial (sometimes climbing in undergrowth), up to 0.8 m high. Leaf blades up to 130 mm long, 4-20 mm wide. Spikelets 2-4 mm long. Inflorescence of racemes, with 6-20 spikelets; glumes with smooth sticky awns 3-14 mm long.
Trailing perennial, stems to 80 cm. Leaves lanceolate to ovate. Spikelets 6-20 in racemes, awns smooth, sticky.
Moist forests, thickets, and banks of rivers and streams, Mexico and the West Indies to Argentina.