两蕊甜茅 liang rui tian mao

Poa lithuanica Gorski in Eichwald, Naturihist. Skizze 117. 1830; Glyceria aquatica (Linnaeus) J. Presl & C. Presl subsp. debilior (Trinius ex Fr. Schmidt) T. Koyama; G. aquatica var. debilior Trinius ex Fr. Schmidt; G. debilior (Trinius ex Fr. Schmidt) Kudo; G. orientalis Komarov.

Perennial, rhizomatous. Culms soft, 60–150 cm tall, 3–5 mm in diam. Leaf sheaths not prominently keeled, lower sheaths scabrid; leaf blades flat, soft, thin, up to 30 cm × 4–9 mm, scabrid, apex acute; ligule 2–3 mm. Panicle ovate in outline, 15–30 cm, exserted, spikelets many; branches 2–4 per node, spreading, often flexuous, sometimes nodding, filiform, scabrid. Spikelets elliptic to ovate-oblong, 5–8 mm, florets 3–6, bright green or purple tinged; rachilla densely scabrid; glumes ovate, membranous, 1-veined, lower glume 1.2–1.8 mm, upper glume 1.7–2.5 mm, apex subobtuse; lemmas lanceolate-oblong, 2.5–4 mm, thinly herbaceous, often minutely granular or scaberulous, 7-veined, veins scabrid, apex membranous, obtuse; palea as long as or slightly longer than lemma, keels wingless, scaberulous, apex emarginate. Stamens 2, anthers 0.5–0.8 mm. Fl. Jun–Aug. 2n = 20.

Swampy forests, forest margins, streamsides; 600–1800 m. Jilin, Liaoning [Japan, Korea, Mongolia, Russia; SW Asia (Caucasus), C and N Europe].

This is a generally more slender species than Glyceria leptolepis, the other species in China with only 2 anthers. The basal culm internodes are not hard and canelike as in G. leptolepis, but flatten on pressing.