| J. Gabriel Sánchez-Ken |
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;
lodicules2, 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.
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.