Poaceae tribe Thysanolaeneae

C.E. Hubb.
Treatment appears in FNA Volume 25. Treatment on page 349.

Plants perennial; cespitose, shortly rhizomatous, reedlike. Culms 1.5-4 m, woody, persistent, glabrous, usually not branched above the base; internodes solid. Sheaths open; auricles sometimes present; ligules membranous to somewhat leathery, entire, minutely erose, or ciliolate; pseudopetioles poorly developed; blades flat, disarticulating from the sheaths when old, cross venation not evident. Inflorescences terminal, open diffuse panicles. Spikelets solitary, pedicellate, terete, with 2 (3-4) florets, lowest floret sterile; rachillas prolonged, often terminating in a rudimentary floret; disarticulation at the pedicel bases, subsequently below the spikelets. Glumes membranous, shorter than the florets, 0-1-veined, obtuse; lowest florets equaling the upper florets, sterile; lowest lemmas membranous, 1-3-veined; lowest paleas not present; upper florets bisexual; upper lemmas membranous, 3-veined, unawned, marginal veins with papillose-based hairs, hairs 0.8-1.5 mm, strongly diverging at maturity; upper paleas about 1/2 as long as the lemmas, apices notched; lodicules 2, free, broadly cuneate, truncate to irregularly lobed; anthers 2 (3). Caryopses nearly spherical to broadly ovoid; hila subbasal, punctate; embryos large, about 3/4 as long as the caryopses. x = 12.

Discussion

The tribe Thysanolaeneae is native to tropical Asia and includes only the monotypic genus Thysanolaena. It could be included in a more broadly circumscribed Centotheceae, but the members of that tribe needs further study before changes to its circumscription are adopted.

Selected References

None.

Lower Taxa

"decumbent" is not a number.

J. Gabriel Sanchez-Ken +
C.E. Hubb. +
1 (?) +  and 3 (?) +
keeled +  and rounded +
pseudopetiolate +  and branching +
divergent +  and parallel +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
disarticulating +
usually linear +  and lanceolate occasionally ovate +
spikelike +
nearly spherical +  and broadly ovoid +
fusoidlike +
persistent +
ascending +  and erect +
150 cm1,500 mm <br />1.5 m <br /> (400 cm4,000 mm <br />4 m <br />) +
capillary +
pistillate +  and staminate +
sometimes longer +
basal +  and distal +
rudimentary +
round +  and compressed +
reduced +
subtending +
membranous +
papillose-based +
uncinate +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
paniculate +  and racemose +
leathery +  and membranous to somewhat +
inconspicuous +
truncate +  and irregularly lobed +
concealed +  and prominent +
2 +  and 1 +
well-developed +
dry +  and fleshy +
not evident +
1 +  and 60 +
unisexual +  and bisexual +
2 (?) +  and 3 (?) +
free +  and fused +
triangular +  and dome--shaped +
Gramineae +
Poaceae tribe Thysanolaeneae +
Poaceae subfam. Centothecoideae +
membranous +
plant +  and cespitose +
aquatic +  and terrestrial +